Developmental disturbances of teeth.pptx

This presentation is an overview of different developmental disturbances of teeth and few references in for their management in pedodontist perspective.

1. Developmental Disturbances of Teeth Dr. Revanuru Swathi 1 st MDS Department of Pediatric and Preventive Dentistry

2. Learning Objectives To understand and explain different developmental disturbances of teeth To recall the etio -pathogenesis of different developmental disturbances of teeth To apply this knowledge in diagnosing and managing them in day to day practice

3. Textbook References "Oral and Maxillofacial Pathology" by Brad W. Neville, Douglas D. Damm , Carl M. Allen, and Angela C. Chi. Shafer, hine and levy textbook of oral pathology 9 th edition. Mc donald , Avery DR,Dean JA.Dentistry for the child and Adolescent "Ten Cate's Oral Histology: Development, Structure, and Function"* by Antonio Nanci . "Textbook of Oral Pathology" by Anil Govindrao Ghom and Shubhangi Mhaske . S.G.Damle Textbook of Pediatric dentistry ,5 th edition

4. BinnieMatalova , E & Fleischmannova , J & Sharpe, P.T. & Tucker, Abigail. (2008). Tooth Agenesis: from Molecular Genetics to Molecular Dentistry. Journal of dental research. 87. 617-23. 10.1177/154405910808700715 American Academy of Pediatric Dentistry. Management of the developing dentition and occlusion in pediatric dentistry. The Reference Manual of Pediatric Dentistry. Chicago, Ill.: American Academy of Pediatric Dentistry; 2023:466-83 Mallineni , Sreekanth . (2014). Supernumerary Teeth: Review of the Literature with Recent Updates. Conference Papers in Science. 2014. 10.1155/2014/764050. Negi , Anurag et al. “Solitary median maxillary central incisor syndrome: A rare entity.”  Journal of oral and maxillofacial pathology : JOMFP  vol. 24,2 (2020): 402. doi:10.4103/jomfp.JOMFP_183_19 Ben Salem, Mouna et al. “Fusion or Gemination ? Diagnosis and Management in Primary Teeth: A Report of Two Cases.”  Case reports in dentistry  vol. 2021 6661776. 1 Jun. 2021, doi:10.1155/2021/666177 Mohammad Owaise Sharif, Ahmed F, Nazir M. Multiple Recurrent Supernumerary Teeth: A Case Report. Orthodontic update. 2019 Jan 2;12(1):18–20. Bds , San & V, Vinothini & G S, Prathima . (2018). Twinning in Primary Dentition – A Case Report. Journal of Scientific Dentistry. 8. 10-12. 10.5005/jsd-8-1-10. ‌ Article References

5. 8. Hunasgi , Santosh et al. “A Rare Case of Twinning Involving Primary Maxillary Lateral Incisor with Review of Literature.”  Journal of clinical and diagnostic research : JCDR  vol. 11,2 (2017): ZD09-ZD11. doi:10.7860/JCDR/2017/23510.9212 9. Mosharraf , Ramin . (2013). Prevalence of the carabelli trait in Iranian adolescents. International Journal of Nanomedicine . 4. 12-15. 10.4103/0976-433X.116827. 10. Sarpangala , Mythri , and Ashwin Devasya . “Occurrence of Cusp of Carabelli in Primary Second Molar Series of three Cases.”  Journal of clinical and diagnostic research : JCDR  vol. 11,3 (2017): ZR01-ZR02. doi:10.7860/JCDR/2017/24040.9340 11. Bhavyaa , R., Sujitha , P., Muthu , M., & Kirthiga , M. (2020). Prevalence of Cusp of Carabelli and its caries susceptibility – an ambidirectional cohort study. Australian Dental Journal , 65 (4), 294-301. https://doi.org/10.1111/adj.12795 12. Gupta, Disha . “ Parastyle Cusp: A Rare Morphologic Variant of Maxillary Second Molars.” Journal of Forensic Dental Sciences (2018): n. pag . Print. 13. Narsapur SA, Choudhari S. Bilateral protostylids and parastyles associated with hypodontia of maxillary lateral incisor: Report of two rare clinical cases. Journal of Indian Academy of Oral Medicine and Radiology [Internet]. 2017 Mar 1 ‌

6. 14. Shunmugavelu K. Talon Cusps-A Review of Literature. Borno Medical Journal [Internet]. 2021 [cited 2023 May 17];18(2). 15. Lekhwani PS, Marwah N, Sharma Y, Yadav P. A rare occurrence of nonsyndromic focal microdontia of primary teeth with hypodontia of permanent teeth in a pediatric patient. J Oral Maxillofac Pathol . 2022 Feb;26( Suppl 1):S22-S25. doi : 10.4103/jomfp.jomfp_62_21. Epub 2022 Feb 28. PMID: 35450236; PMCID: PMC9017845. ‌

7. Contents Introduction Stages of tooth development Classification Variation in Size of teeth Variation in number of teeth Variation in Shape/form of teeth Variations in structure of teeth Variations in Eruption of teeth Conclusion

8. INTRODUCTION Developmental dental anomalies are marked deviations from the normal colour, contour, size, number, and degree of development of teeth. Local as well as systemic factors may be responsible for these developmental disturbances Such influences may begin before or after birth, hence deciduous or permanent teeth may be affected.

9. CLASSIFICATION DEVELOPMENTAL DISTURBANCES OF HARD TOOTH STRUCTURE Developmental disturbances in size of teeth Microdontia Macrodontia Developmental disturbances in shape of teeth Gemination Fusion Concrescence Lobodontia Globodontia Dilaceration Talons cusp Dens in dente

10. Dens evaginatus Enamel pearl Taurodontism Supernumerary roots Developmental disturbances in number of teeth Anodontia Supernumerary teeth Developmental disturbances in structure of teeth Amelogenesis imperfecta Environmental enamel hypoplasia Dentinogenesis imperfecta Dentin dysplasia Regional odontodysplasia Dentin hypocalcification

11. Developmental disturbances in eruption of teeth Premature eruption Eruption sequestrum Delayed eruption Multiple unerupted teeth Retained deciduous teeth Embedded and impacted teeth Ankylosed deciduous teeth

12. DEVELOPMENTAL DISTURBANCES IN SIZE OF TEETH

13. Microdontia Means presence of unusually small teeth. Boyle 1955 in general microdontia teeth are small, crowns are short and normal contacts between teeth are frequently missing. Ufomata 1988 says it can be of whole crown, only crown or only roots. Etiology: Heredity( major factor) Both genetic & environmental influences. Three types of microdontia are recognized (1) True generalized microdontia (2) Relative generalized microdontia (3) Microdontia of a single tooth.

14. Three types of microdontia are recognized (1) T rue generalized microdontia All teeth are smaller than normal, exceedingly rare, teeth are well formed E.g. Pituitary dwarfism, Downs Syndrome, Rieger anomaly, oro-faciodigital syndrome (type 3) Oculo - mandibulo -facial syndrome, h/o chemoradiotherapy (2 ) Relative generalized microdontia Normal or slightly smaller than normal Jaw seems to be some what larger than normal & illusion of true microdontia . Person may inherit the jaw size from one parent & teeth size from other parent. Hereditary factors plays imp. role. ( 3) Focal / Localized microdontia Common conditions, usually max. lateral incisor & 3 rd molar. PEG LATERAL : Instead of parallel or diverging mesial and distal surfaces, the sides converges or taper together incisally , forming a peg-shaped or cone shaped crown.

15. Occurrence in children : Rare (less than 1% ) in primary teeth More common (2.5%) in permanent teeth. Females more frequently affected than males Etiology : Multifactorial Generalized microdontia is rare and may be associated with congenital hypopitutarism or exposure to radiation or chemotherapy during dental development In contrast, localized microdontia is more common and is frequently followed by hypodontia .

16. Clinical significance : Spacing due to microdontia is disturbing cosmetically. Midline shift Reduced overjet Mesial movement of upper molars Syndromes in which microdontia may be seen include the downs syndrome, the ectodermal dysplasia syndrome, focal dermal hypoplasia . Treatment : Un-erupted microdonts may require surgical removal to prevent the formation of cysts. Erupted microdonts , peg laterals especially, may cause cosmetic concern. Such teeth may be restored to resemble normal sized teeth, typically with composite build ups or crowns. Orthodontics may be required in severe cases to close gaps between the teeth

17. Lekhwani PS, Marwah N, Sharma Y, Yadav P. A rare occurrence of nonsyndromic focal microdontia of primary teeth with hypodontia of permanent teeth in a pediatric patient. J Oral Maxillofac Pathol . 2022 Feb;26( Suppl 1):S22-S25. doi : 10.4103/jomfp.jomfp_62_21. Epub 2022 Feb 28. PMID: 35450236; PMCID: PMC9017845. A 10‑year‑old male patient reported with a chief complaint of unerupted permanent teeth in the lower front region. History was non contributory ( medical, dental and familial).

18. Lekhwani PS, Marwah N, Sharma Y, Yadav P. A rare occurrence of nonsyndromic focal microdontia of primary teeth with hypodontia of permanent teeth in a pediatric patient. J Oral Maxillofac Pathol . 2022 Feb;26( Suppl 1):S22-S25. doi : 10.4103/jomfp.jomfp_62_21. Epub 2022 Feb 28. PMID: 35450236; PMCID: PMC9017845. To verify whether the patient had any tooth deficiency, a panoramic radiograph was taken. The smaller size of lower primary central incisors was even evident on OPG . Furthermore, the permanent tooth germs of bilateral mandibular central incisors and right mandibular second premolar were absent. Based on clinical and radiographic findings, the patient was diagnosed with focal microdontia of primary teeth (71 and 81) along with hypodontia of permanent teeth (31, 41 and 45). Since the patient was completely normal with no other past medical history, it was diagnosed as nonsyndromic focal microdontia with hypodontia .

19. Macrodontia When teeth are physically larger than usual Fusion or gemination should not be included. Three types of macrodontia are recognized: (1) True generalized macrodontia (2) Relative generalized macrodontia (3) Macrodontia of a single tooth. Occurrence in children : Rare ( 1.1%) in permanent dentition Etiology : Hereditary Klinefelter syndrome Pitutary gigantism Insulin resistant diabtetes Hemifacial hypertrophy

20. True generalized macrodontia All teeth are larger than normal E.g. Pituitary gigantism Exceedingly rare Relative generalized macrodontia Normal or slightly larger than normal Jaw seems to be some what smaller than normal & makes illusion of true macrodontia . Person may inherit the jaw size from one parent & teeth size from other parent. Hereditary factors plays imp. role. Macrodontia involving a single tooth Uncommon conditions, seen incase of hemi -hypertrophy of the face, in which the teeth of involved side may be considerably larger. Usually seen with mandibular 3 rd molars

21. Localization : Lower third molars and second premolars Upper central incisors Frequent bilateral symmetry Management: Aesthetic restoration Orthodontic treatment of the crowding Extraction

22. DEVELOPMENTAL DISTURBANCES IN NUMBER OF TEETH

23. Anodontia – True anodontia - i ) Total ii) Partial- Hypodontia Oligodontia Induced or false anodontia Pseudo anodontia B) Supernumerary teeth

24. True Anodontia Congenital abscence of teeth Total Anodontia All teeth are missing Both deciduous and permanent dentition Rare condition Hereditary ectodermal dysplasia Partial Anodontia One or few teeth missing Relatively common condition

25. Partial Anodontia Involves one or more teeth Common condition Maxillary lateral incisors, maxillary or mandibular 2 nd premolars, third molars Hypodontia – Lack of developmment of one or more teeth Etiology : Autosomal dominant with incomplete penetrance , trauma, infections, radiation overdose, glandular dysfunction, systemic conditions like rickets, rubeola during pregnancy Abscence of appropriate / sufficient segments of dental lamina Clinical features : Missing teeth : primary, permanent and other abnormalities like fusion, ankylosis , short root Treatment: Orthodontic space closure/ rehabilitation with fixed or removable partial dentures/ implants

26. Oligodontia - Lack of development of six or more teeth Etiology : Oligodontia is thought to have a significant genetic basis because it is associated with mutations in several genes, the protein products of which regulate odontogenesis . Oligodontia may also be associated with environmental influences.

27. Matalova , E & Fleischmannova , J & Sharpe, P.T. & Tucker, Abigail. (2008). Tooth Agenesis: from Molecular Genetics to Molecular Dentistry. Journal of dental research. 87. 617-23. 10.1177/154405910808700715.

28. With congenitally missing permanent maxillary incisor(s) or mandibular second premolar(s), the decision to extract the primary tooth and close the space orthodontically versus opening the space orthodontically and placing a prosthesis or implant depends on many factors. For maxillary laterals, the dentist may move the maxillary canine mesially and use the canine as a lateral incisor or create space for a future lateral prosthesis or implant. Factors that influence the decision are: (1) patient age; (2) canine shape; (3) canine position; (4) child’s occlusion and amount of crowding; (5) bite depth; and (6) quality and quantity of bone in the edentulous area. Early extraction of the primary canine and/or lateral may be needed. Opening space for a prosthesis or implant requires less tooth movement, but the space needs to be maintained with an interim prosthesis, especially if an implant is planned. Moving the canine into the lateral position produces little facial change, but the resultant tooth size discrepancy often does not allow a canine guided occlusion. American Academy of Pediatric Dentistry. Management of the developing dentition and occlusion in pediatric dentistry. The Reference Manual of Pediatric Dentistry. Chicago, Ill.: American Academy of Pediatric Dentistry; 2023:466-83.

29. For a congenitally missing premolar, the primary molar either may be maintained or extracted with subsequent placement of a prosthesis or orthodontically closing the space. Maintaining the primary second molar may cause occlusal problems due to its larger mesiodistal diameter, compared to the second premolar. Reducing the width of the second primary molar is a consideration, but root resorption and subsequent exfoliation may occur. In crowded arches or with multiple missing premolars, extraction of the primary molar(s) can be considered, especially in mild Class III cases. For a single missing premolar, if maintaining the primary molar is not possible, placement of a prosthesis or implant should be considered. Preserving the primary tooth may be indicated in certain cases. However, maintaining a submerged ankylosed tooth may increase likelihood of alveolar defect which can compromise later implant success. Consideration for extraction and space maintenance may be indicated. Consultation with an orthodontist and/or prosthodontist may be considered. American Academy of Pediatric Dentistry. Management of the developing dentition and occlusion in pediatric dentistry. The Reference Manual of Pediatric Dentistry. Chicago, Ill.: American Academy of Pediatric Dentistry; 2023:466-83.

30. Pseudoanodontia It is a descriptive term that indicates clinical but not radiographic absence of teeth and should normally be present in the oral cavity for the patients dental and chronological age. In these cases radiographic examination discloses the teeth in the jaws. More commonly the deciduous teeth have been shed, but the permanent ones failed to erupt. False anodontia False anodontia is the abscence of teeth due to injury, accident, delayed eruption, extraction or exfoliation.

31. Supernumerary teeth Supernumeray teeth are those that exceed the normal dental formula. This phenomenon is also known as hyperdontia and can occur in solitary or multiple form, may be unilateral or bilateral and affect one or both the arches. Teeth may have Normal morphology Rudimentary Miniature Supernumerary deciduous teeth – male > female, maxillary anterior > mandibular anteriors Supernumerary permanent teeth – male > female, maxilla > mandible Mallineni , Sreekanth . (2014). Supernumerary Teeth: Review of the Literature with Recent Updates. Conference Papers in Science. 2014. 10.1155/2014/764050.

32. Etiology : The etiology of supernumerary teeth remains unclear and various theories have been postulated to explain how and why they develop. Various studies have claimed that they are the result of hyperactivity of the dental lamina where the epithelial cells that form supernumerary teeth remain for long periods. Other studies show that the main etiological factor is genetic predisposition , having to do with a disorder associated with a dominant autosomal gene. Elsewhere, they are thought to be associated with diverse syndromes or due to phylogenetic theory, environmental factors or tooth germ dichotomy .

33. Phylogenetic theory , although it has been discounted as it would only explain single anomalies of ectopic teeth , proposes that the presence of supernumerary teeth involves a regression towards now extinct ancestral tissues. With regard to environmental factors, in tooth germ dichotomy , an imbalance between molecules can cause the tooth germ to divide into two parts, of equal or different size, which will result in either two teeth of the same size or one normal and one dysmorphic tooth

34. Classification Supernumerary teeth can be classified according to chronology, location, morphology and orientation.

35. Mohammad Owaise Sharif, Ahmed F, Nazir M. Multiple Recurrent Supernumerary Teeth: A Case Report. Orthodontic update. 2019 Jan 2;12(1):18–20. ‌

36. Complications : Midline Diastema : Presence of erupted and unerupted mesiodens may cause midline diastema . A retrospective analysis showed 10% of cases with SNT cases exhibited midline diastema . Delayed or Failure of Eruption : Supernumerary tooth is the common reason for the delayed or failure of eruption in premaxillary region. Prevention or delayed eruption of associated permanent teeth and tuberculate ST are the possible reasons for failure of eruption of maxillary permanent incisors. Supernumerary teeth in other locations may also cause failure of eruption of adjacent teeth.

37. Displacement : Displacement of the crowns of the adjacent teeth is a common feature in cases that associated with ST. The amount of displacement varies from a mild rotation to complete displacement. Supernumerary teeth cause severely rotated incisors and sometimes remain unerupted . Self-correction and correct alignment may result in early removal of the causative ST. Crowding : Any form of ST can cause this complication; erupted or unerupted supplemental ST most often leads to crowding. Root Resorption : Root resorption of adjacent teeth sometimes leads to loss of tooth vitality. Alveolar Bone Grafting : Secondary alveolar bone grafting may be compromised due to ST in patients with cleft lip and palate. Unerupted ST in the cleft site is normally removed at the time of bone grafting. Implant Site Preparation : The presence of an unerupted ST in a potential implant site may compromise implant placement.

38. Ectopic Position : Ectopic eruption of ST has been reported, among these frequently reported in the nasal cavity. Clinically, a white mass may be seen in the nasal area, radiographically appearing as a tooth-like radiopacity . Late Forming Supernumerary Teeth : Patients with a history of anterior conical or tuberculate supernumerary teeth at an early age have a 24% possibility of developing single or multiple supernumerary premolars at late age. Root Abnormalities : Dilaceration is a developmental anomaly in the tooth shape and its structure, which may happen as sharp bending of the tooth in either the crown or the root portion. Loss of tooth vitality has been reported in rare conditions. Cyst Formation : It has been reported that cyst formation due to ST was observed in 11% of the cases where dentigerous cyst is common type.

39. Management The treatment options for managing ST depend on their orientation and position, the age of the patient, and any associated complications. There are two common opinions for removal of ST as soon as they are identified. Few authors reported that early identification and removal of ST, in contrast to some authors which may suggest abrupt removal of ST, are not essential if there is no associated pathology. Hogstrom and Anderson suggested two different opinions where the ST should be removed as early as upon identification or should wait until complete root formation of adjacent teeth. The optimal time for surgical intervention, however, remains contentious.

40. It is very important to remove ST at a young age if it is damaging adjacent teeth or causing any other complication. Recently, Omer and colleagues reported based on a retrospective analysis the ideal age of removal of ST 6 to 7 years. The majority of delayed permanent incisors erupt spontaneously if sufficient space is created at the time of removal of the ST and maintenance of postoperative space is needed. Permanent maxillary incisor teeth still remained un-erupted with near complete apical formation; orthodontic bracket and chain may be used to facilitate orthodontic traction. In some cases based on angulations of impacted teeth caused by ST, orthodontic bracket and chain placed at the time of surgical removal ST may be essential for the eruption.

41. Management and treatment of hyperdontia differs if the tooth is primary or permanent. Primary supernumerary teeth normally are accommodated into the arch and usually erupt and exfoliate without complications. Extraction of an unerupted supernumerary tooth during the primary dentition usually is not done to allow it to erupt; surgical extraction of unerupted supernumerary teeth can displace or damage the permanent incisor. Removal of a mesiodens or other permanent supernumerary incisor results in eruption of the permanent adjacent normal incisor in 75 percent of the cases. Extraction of an unerupted supernumerary during the early mixed dentition allows for a normal eruptive force and eruption of the adjacent normal permanent incisor. Later removal of the mesiodens reduces the likelihood that the adjacent normal permanent incisor will erupt on its own, especially if the apex is completed. Inverted conical supernumeraries can be harder to remove if removal is delayed, as they can migrate deeper into the jaw. After removal of the supernumerary, clinical and radiographic follow-up is indicated in six months to determine if the normal incisor is erupting. If there is no eruption after six to 12 months and sufficient space exists, surgical exposure and orthodontic extrusion is needed. American Academy of Pediatric Dentistry. Management of the developing dentition and occlusion in pediatric dentistry. The Reference Manual of Pediatric Dentistry. Chicago, Ill.: American Academy of Pediatric Dentistry; 2023:466-83.

42. DEVELOPMENTAL DISTURBANCES IN SHAPE AND FORM OF TEETH

43. Crown Fusion Gemination Twinning Taurodontism Accessory cusps Dens evaginatus Dens invaginatus Mulberry molars Hutchinsons incisors Lobodontia Globodontia

44. Root Concresence Enamel pearl Dilaceration Flexion Supernumerary roots

45. FUSION Union of two normally separated tooth germs If union occurs before calcification – teeth completely united If union occurs after calcification – roots get fused Primary (2-3%) > Permanent (1-2%) Can occur between same dentition or primary to permanent dentition ( Caceda 1994) Fusion of primary teeth may lead to congenital absence of permanent teeth. Associated syndrome : Solitary median maxillary central incisor syndrome

46. Clinical features : Fusion may be complete or incomplete. The tooth may have separate or fused root canals. Teeth demonstrate a pronounced labial or lingual groove. Affects both primary and permanent teeth Most frequently occurs in the mandible. Clinical significance: Fusion results in spacing. The labial and lingual grooves are prone to develop caries.

47. Solitary median maxillary central incisor syndrome Very rare condition Present as single midline symmetrical maxillary central incisor - Due to mutation in SHH gene SMMCI can occur as an isolated anomaly or in combination with other morphologic defects, such as hypotelorism , indistinct philtrum , absence of the frenulum of the upper lip, vomerine ridge and nasal obstruction or septal deviation.

48. Case report A 9-year-old female patient reported to the orthodontic clinic with a chief complaint of unesthetic appearance due to the presence of a single large upper front tooth. The central portion of the upper lip was high with an indistinct philtrum which is characteristic of SMMCI syndrome. On intraoral examination, the patient was in a mixed dentition stage with one large maxillary central incisor situated exactly in the midline . Maxillary and mandibular arches were symmetrical with angles Class I molar relationship. The patient had a V-shaped palate and marked midpalatal vomerine ridge. The labial frenulum of the upper lip and incisive papilla were absent. A periapical radiographic examination showed a central incisor having only single root canal . Negi , Anurag et al. “Solitary median maxillary central incisor syndrome: A rare entity.”  Journal of oral and maxillofacial pathology : JOMFP  vol. 24,2 (2020): 402. doi:10.4103/jomfp.JOMFP_183_19

49. Treatment alternatives Negi , Anurag et al. “Solitary median maxillary central incisor syndrome: A rare entity.”  Journal of oral and maxillofacial pathology : JOMFP  vol. 24,2 (2020): 402. doi:10.4103/jomfp.JOMFP_183_19 As the main concern of the patient was esthetics, the only way to achieve this in patients with SMMCI is to provide space for the second central incisor. At appropriate age, space can be created by an orthodontist using expansion appliance to widen the palate, thus providing sufficient space for the SMMCI tooth to be moved to one side of midline and creating space for contralateral missing central incisor to be replaced with prosthesis. After creation of space, the incisor may be replaced using fixed prosthodontic rehabilitation. Among the fixed prosthodontic treatment, options are single‑tooth implant, Maryland retainers and bridge. Fixed partial dentures/bridge are not indicated in adolescents. A single‑tooth implant is also not indicated unless alveolar growth is complete as it may result in implant position which is different from adjacent normal teeth which keep on growing in adolescents. A modified removable orthodontic retainer with artificial central incisor is the easiest treatment option available till the time growth is complete and an implant or bridge can be used. After completion of growth (17–18 years of age), SMMCI tooth can be recontoured using a labial veneer to create the anatomical form of appropriate size and shape along with prosthodontic rehabilitation of missing teeth.

50. Geminated teeth are the anomalies which arise from an attempt at division of single tooth germ by an invagiation , with resultant incomplete formation of two teeth. Tooth count is normal. Clinical features : Seen in both primary and permanent dentitions Has higher frequency in anterior and maxillary regions Incisors and canines are most commonly affected Teeth demonstrate a pronounced labial or lingual groove. Cause : unknown but trauma may be the possible cause Clinical significance : Gemination can result in crowding and delayed or ectopic eruption of the underlying permanent teeth and hence have to be extracted in certain cases. The labial or lingual groove are prone to develop caries and hence in such cases fissure sealant should be used. GEMINATION

51. Differentiating factors Mader’s “two tooth” rule can be a practical method for differentiating between fusion and gemination . In fact, if the abnormal tooth is considered as “two teeth” and the total number of teeth in the dental arch is normal, fusion is therefore determined. However, when the atypical tooth is considered as “two teeth” and the resulting number of teeth in the dental arch is higher than usual, then, the diagnosis is either gemination or fusion between normal and supernumerary teeth. Ben Salem, Mouna et al. “Fusion or Gemination ? Diagnosis and Management in Primary Teeth: A Report of Two Cases.”  Case reports in dentistry  vol. 2021 6661776. 1 Jun. 2021, doi:10.1155/2021/6661776

52. Treatment of Gemination and fusion: Deciduous dentition: If Crowding, abnormal spacing, delayed eruption of permanent teeth. then Extraction. Otherwise: Surgical division & endodontic treatment is done

53. Twinning: Coined by levitas 1965 Twinning is referred to the development of two separate teeth that arose from the complete separation of one tooth bud. Production of equivalent structures by division resulting in one normal and one supernumerary tooth Occurrence of deep groove in some cases of twinning makes them vulnerable to periodontal diseases and caries. The problems, mostly if the anterior teeth are involved, differ from spacing problems, tooth malalignment , aesthetic problems, arch asymmetry, periodontal involvement and impeding the eruption of the adjacent tooth.  

54. Case report Bds , San & V, Vinothini & G S, Prathima . (2018). Twinning in Primary Dentition – A Case Report. Journal of Scientific Dentistry. 8. 10-12. 10.5005/jsd-8-1-10. A 5 year old girl reported with a chief complaint of decayed tooth in upper front teeth region. Her medical history was not remarkable. On clinical examination tooth number 51 showed twinning and caries involving enamel and dentin in both the components of the double tooth. There was clinical pulp exposure in the mesial component and arrested caries in the distal component. The tooth was associated with a draining sinus tract . Intraoral periapical radiograph revealed presence of separate roots for the two components resulting in mirror image teeth. Permanent incisors did not show any anomalies . The caries in the mesial component of the twinned 51 appeared deep and hence it was decided to perform pulpectomy for the mesial component first and restore the distal component with GIC and observe for the healing of sinus. The sinus tract persisted for more than one week after initiation of pulpectomy in the mesial component and hence pulpectomy was performed for the distal component also. After one week it was observed that the sinus was healing and canals were obturated with metapex and tooth restored with composite

55. CONCRESCENCE Teeth are united by the cementum only. It arises as a result of traumatic injury or crowding of teeth with resorption of the interdental bone so that the two teeth are in approximate contact and become fused by deposition of cementum . Clinical features: Most commonly seen in the posterior and maxillary regions. It can occur before or after the teeth have erupted. Clinical significance: No therapy is usually required unless the union interferes with eruption, then surgical removal may be warrented .

56. Taurodontism Originated by Sir Arthur Keith in 1913 It is the enlargement of the body and pulp chamber of a multirooted teeth with apical displacement of the pulpal floor Bull like teeth The degree of taurodontism has been classified into :

57. Causes : (Enumerated by Mangion ) Specialized or retrograde character Primitive pattern Mendelian recessive trait Mutation resulting from odontoblastic deficiency during dentinogenesis of roots Failure of hertwig’s epthelial sheath to invaginate at proper horitzontal level. ( hammer and his associates )

58. Clinical features : Either deciduous or permanent dentition Molars Unilateral or bilateral Radiographic features : Involved teeth – rectangular shape Pulp chamber – extremely large- much greater apico-occlusal height Pulp lacks usual constriction at cervical of tooth Roots – exceedingly short Furcation – only few mm above the apices of roots.

59. Syndrome associated : Klinefelter’s syndrome Trichodento -osseous syndrome Ectodermal dysplasia Downs syndrome Diagnosis : Made only radiologically Treatment : No Specific therapy

60. ACCESSORY CUSPS Cuspal morphology of the teeth exhibit minor variations: CUSP OF CARABELLI TALONS CUSP PARASTYLID

61. CUSP OF CARABELLI The cusp of Carabelli , is also known as Carabelli tubercle, carabelli cusp, fifth cusp, atrophied cusp, supplementary cusp,   tuberculum anomale  of Georg Carabelli . It was first described in 1842 by the Hungarian Georg Carabelli . This is a morphological variation which takes the form of fifth cusp or it can grade down to a series of grooves, depressions or pits on the mesial portion of the lingual surface. This cusp is found palatal to the mesiolingual cusp of maxillary first permanent molar, which is the largest of the well-developed cusps and becomes less prominent in second and third molars.

62. Dahlberg’s(1963) scale for the determination of degree and expression of carabelli cusps Mosharraf , Ramin . (2013). Prevalence of the carabelli trait in Iranian adolescents. International Journal of Nanomedicine . 4. 12-15. 10.4103/0976-433X.116827.

63. The aetiology is unknown, but it is suggested that it might be due to overactivity of dental lamina. The incidence of this cusp is more in maxillary permanent first molar and rarely seen in primary second molars. The presentation is usually bilaterally.  The functional perspective being able to bear the biomechanical stress by broadening the occlusal table of molar tooth. Even though it is non-functional, it can be used to distinguish population, also used in forensic and anthropological studies . The groove separating the cusp may be prone to caries and there might be problems in placement of orthodontic bands due to improper adaptation Sarpangala , Mythri , and Ashwin Devasya . “Occurrence of Cusp of Carabelli in Primary Second Molar Series of three Cases.”  Journal of clinical and diagnostic research : JCDR  vol. 11,3 (2017): ZR01-ZR02. doi:10.7860/JCDR/2017/24040.9340

64. The authors suggest that the presence of this trait might lead to placement of an oversized prefabricated stainless steel crown on the primary maxillary second molar which might further hinder the eruption of adjacent permanent teeth. Hence, complete removal of this trait before the placement of prefabricated stainless steel crown might be required . With regard to oral surgery, the presence of this trait can lead to fracture of molar teeth during extraction as the molar forceps cannot accommodate this trait. Thus , practitioners should be cautioned to select a larger size forceps that can accommodate this trait. In the field of orthodontics, prefabricated orthodontic bands that are commonly used might not adapt well on a tooth with this trait. Hence, during orthodontic treatment, a larger-sized band needs to be chosen to accommodate the CoC on the molars. These large-sized bands might fit loosely, thus, leaving a space between the band and the teeth. Accumulation of food and plaque might occur in this space leading to dental caries and periodontal diseases in this area.  Hence, after placement of preformed orthodontic bands, care should be taken to adapt the preformed band along the trait or fill the space with restorative material to avoid accumulation of food or plaque in that area. Manual adaptation of the stainless steel bands can be preferred over preformed orthodontic bands in the presence of this trait . Bhavyaa , R., Sujitha , P., Muthu , M., & Kirthiga , M. (2020). Prevalence of Cusp of Carabelli and its caries susceptibility – an ambidirectional cohort study. Australian Dental Journal , 65 (4), 294-301. https://doi.org/10.1111/adj.12795

65. Protostylid / Parastyle / paramolar cusp / paramolar tubercle A protostylid is a supernumerary cusp located on the mesial half of the buccal surface on the upper and lower molars. The etiology of extra cusp formation or abnormal shape is unknown. However, it was said that these features are probably due to over activity of the dental lamina, but at present, it is believed that PAX and MSX genes are responsible for the abnormal shape of the teeth.

66. It is considered as a cingulum derivative expressed usually on the buccal surface of the paracone of upper molars and rarely on the metacone of the upper molars. They have a bilateral occurrence in deciduous dentition and unilateral occurrence in permanent dentition. The presence of parastyle or an extracusp poses a dental problem to clinicians such as dental caries; sensitivity/ devitalization due to attrition/fracture; premature tooth contact; pulpal or periapical disease; difficulty in placement of stainless steel crowns; interference with cementation of brackets, bands, and alignment of wires during orthodontic treatment, increased chances of food lodgment leading to plaque accumulation causing periodontal problems; difficulty in root canal treatment/ pulpectomy and possibility of failure; and sharp extracusps which may result in frictional keratosis . Gupta, Disha . “ Parastyle Cusp: A Rare Morphologic Variant of Maxillary Second Molars.” Journal of Forensic Dental Sciences (2018): n. pag . Print.

67. Narsapur SA, Choudhari S. Bilateral protostylids and parastyles associated with hypodontia of maxillary lateral incisor: Report of two rare clinical cases. Journal of Indian Academy of Oral Medicine and Radiology [Internet]. 2017 Mar 1 ‌ When supernumerary cusps are associated with maxillary molars and premolars, they are termed as parastyle , and when associated with mandibular molars and premolars they are known as protostylid .

68. Talon cusp A talon cusp is an accessory cusp-like dental anomaly that projects from the cingulum or cementoenamel junction to the incisal edge of the maxillary or mandibular anterior teeth in both primary and permanent dentition. The cusp is made up of regular enamel, dentin, and various extensions of pulp tissue, but due to its superimposition on the main pulp chamber, its structure is difficult to ascertain. Aetiology: Outfolding of the inner enamel epithelial cells, as well as a temporary focal hyperplasia of the mesenchymal dental papilla organ or hyperactivity of the dental lamina, was thought to cause it during the morphodifferentiation stage of tooth growth. Patients with Mohr syndrome, Sturge –Weber syndrome, Rubinstein– Taybi syndrome, incontinentia pigmenti achromians , or Ellis–van Creveld syndrome have been reported to have talon cusps Caries susceptibility, occlusal intervention, and impaired esthetics are the most common issues associated with a talon cusp.

69. Hattab and colleagues suggested a classification scheme for these irregular cusps based on their degree of development and extension: Type I is a "true talon," a morphologically well delineated cusp that projects at least half way from the cemento -enamel junction to the incisal edge. Type II is a "semi talon," a morphologically well delineated cusp that projects at least half way from the cemento -enamel junction to the incisal edge length of 1 mm or more but extends less than half the distance between the cementoenamel junction and the incisal tip. Type III is called a "trace talon” since it is inflated and conspicuous, stretches less than half way from the cemento -enamel junction to the incisal tip. A " tracetalon ," or expanded and prominent cingulum , is Type III.

70. Treatment : Small talon cusps are normally asymptomatic, and there is no need for therapy sequential grinding Pit and fissure sealant Pulp therapy Restorative treatment Absolute crown coverage Shunmugavelu K. Talon Cusps-A Review of Literature. Borno Medical Journal [Internet]. 2021 [cited 2023 May 17];18(2). ‌

71. Dens evaginatus Occlusal tuberculated premolar, leong’s premolar, evaginated odontome , occlusal enamel pearl Dens Evaginatus appears clinically as an accessory cusp or globule of enamel on the occlusal surface between buccal and lingual cusp of premolars Unilaterally or bilaterally Pathogenesis : Occurs as a result of proliferation and evagination of an area of inner enamel epithelium and odontogenic mesenchyme into the enamel organ during tooth development. Normally consists of enamel, dentin, & pulp. Prevalence is about 15% in Asians

72. Clinical significance : May interfere with occlusion and should be removed. Removal without loss of vitality may be accomplished through periodic grinding of the cusp. Treatment : Vital teeth : Selective grinding followed by fissure sealing Selective pulpotomy Non vital teeth : Endodontic treatment

73. Dens in dente Also called as Dens Invaginatus , Dilated composite odontome . It is a deep surface invagination of the crown or root that is lined by enamel. Oehlers (1957) divided this condition into 2 forms: Types : Coronal , Radicular Depth of invagination varies from a slight enlargement of the cingulum pit to a deep infolding that extends to the apex. Invagination may be large and resemble a tooth with in a tooth and hence the term Dens in dente( ( pinkham ) Radicular invagination results from infolding of hertwig’s sheath and takes its origin from the root after development is complete. ( Bhatt and dholakia ) Clinical features : Most commonly affected teeth are max permanent lateral incisors. Condition is frequently bilateral.

74. Causes : Increased localized external pressure Focal growth retardation Focal growth stimulation. Coronal dens invaginatus has been classified into three major types: Type I: An invagination that is confined to the crown Type II: Invagination extends below the CEJ & ends in the blind sac that may or may not communicate with adjacent dental pulp. Type III A Extends through the root & perforates in the apical or lateral radicular area without any immediate communication with pulp . Type III B invagination extends into the root and communicates apically through a psuedoforamen with the PDL with no pulpal communication.

75. Radiographically – Pear shaped invagination of enamel and dentin Can cause : caries, pulp infection, premature loss of tooth. Clinical significance: In type I invaginatus the opening of the invagination should be restored after eruption to prevent caries. In larger invagination the content of the lumen and any carious dentin must be removed and calcium hydroxide base must be placed to treat micro communications with the pulp. In type- III endodontic therapy is required.

76. Shovel shaped teeth Shovel-shaped incisors are anatomically characterized by a robust marginal ridge surrounding a deep lingual fossa . Although the etiology of shovel-shaped incisors has been shown to involve a genetic component, these teeth are considered to be anatomical variants rather than morphological defects. They differ considerably among distinct ethnic groups and are commonly found in Asians, Africans and Native Americans, but rarely among Europeans . The condition may affect 9% of the incisors (4% of the central and 5% of the lateral ones).

77. Upper incisors are the teeth most commonly affected . Due to difficulties with proper cleaning, these teeth may end up allowing the entry of microorganisms and irritants, increasing the susceptibility of the dental structure to tooth decay. Chronic irritation results in pulp necrosis and apical abscess, which should be prevented by sealing the cavity with sealant or restorative material and maintaining good oral hygiene.

78. Mulberry molars Also known as moon or fournier molars. Dental considerations usually associated with congenital syphilis. Characterized by multiple rounded rudimentary enamel cusps on permanent 1 st molars Dwarfed molars with cusps covered with globular enamel growths Giving the appearance of a mulberry Syphilitic vasculitis around the time of birth can damage the developing tooth buds and lead to dental anomalies.

79. - Characteristic of congenital syphilis - Lateral incisors are peg-shaped or screw driver – shaped - Widely spaced - Notched at the end - With a crescent- shaped deformity Hutchinson's teeth and mulberry molars often do not require dental treatment. Esthetic restorations may be used to correct the hypoplastic defects as indicated clinically. Hutchinson’s incisors

80. Dilaceration Means an angulation or sharp bend or curve. Angulation or a sharp bend or curve in root or crown of a formed tooth. It arises after an injury that displaces the calcified portion of the tooth germ and the reminder of the tooth is formed at an abnormal angle. Rare deformity Usually seen in deciduous dentition Three main etiologic theories for dilacerations Acute trauma before 4-5 years of age scar formation, Trauma to primary tooth causes a wound – scar prevents normal eruption, root adheres to scar and rotate around this fixed point Primary tooth germ developmental anomaly

81. Clinical features : Most commonly affected teeth are the mandibular third molars followed by the maxillary second premolars and mandibular second molars. - failure of eruption is often seen. - those that achieve eruption follow an altered path. Treatment : Deciduous teeth – extraction Permanent teeth - minor- no treatment Delayed / abnormal eruption- surgical exposure and extraction Non-vital teeth- endodontic treatment / extraction Extensive - extraction

82. Flexion Deviation or bend restricted just to the root portion Usually bend is less than 90 degrees May be a result of trauma to the developing tooth

83. Lobodontia A characteristic pattern of dental anomalies including cone-shaped premolars, multitubercular molar crowns, pyramidal molar roots with single root canals, shovel-shaped incisors with palatal invaginations and hypodontia usually described as lobodontia was recognised as a separate entity.  It is a common finding in turners syndrome, downs syndrome, otodental syndrome. Treatment : conservative Defective structures of the crown are managed endodontically , depending on the extent of pulpal injury caused due to traumatic occlusion, fracture or severe attrition on the evaginated defects.

84. Globodontia Globodontia is characterized by distinctively bulbous, enlarged crowns of molar and primary canine teeth.  Posterior teeth are characterized by bulbous , fused and malformed crowns with almost discernable cusps. It is due to unusual number of well developed cusps and lack of developmental grooves and fossae . It is pathognomonic to odontodental synndrome . Autosomal dominant trait Treatment involves an interdisciplinary approacch with scheduled tooth extraction, ortho treatment and regular follow ups.

85. Ectopic Enamel Enamel in unusual location. Enamel pearl: They are ectopic collections of enamel. These are hemispherical structures consisting of enamel or may contain dentin and pulp. Enamel pearls arise from localized bulging of the odontoblastic layer which provides prolonged contact with hertwigs root sheath triggering the induction of enamel formation. Clinical features: Most frequently found on the roots of maxillary molar. Radiographic features : They appear as well defined, radiopaque nodules along the root surface. Mature internal enamel pearls appear as areas of radio density extending from the dentinoenamel junction into the coronal dentin.

86. Clinical significance: Enamel pearls are areas of weak periodontal attachment. Hence meticulous oral hygiene should be maintained.

87. Supernumerary roots Increase in the number of roots. These are slender outgrowths at the centre of furcation area of molar teeth. Clinical features : Both primary and permanent teeth may be affected. Most commonly affected teeth are the permanent molars. The supernumerary root is usually divergent and easily seen on radiograph. Clinical significance : The accessory roots have to be detected before endodontic therapy and exodntia .

88. Hypercementosis Hypercementosis is the non neoplastic deposition of cementum that s continuous with the normal radicular cementum . It can be localized or generalized : Localized – it is of single tooth. It is usually a reactive, inflammation dependent phenomenon seen on single tooth and usually in relation to periapical osteitis or due to loss of occluding antagonistic tooth. Generalized – affecting many or all teeth, but which is seldom recognised as such, occurs with increasing age, i.e as an age dependent factor. It is also seen as a sign accompanying specific diseases, as for instance, pagets disease of bone. Etiology : Loss of antagonist Inflammation of the root Trauma repair Osteitis deformans or paget’s disease of bone And others like hyperpitutarism , calcinosis , vitamin A deficiency, rheumatic fever.

89. Clinical features: Mandibular molars are the more frequently affected. Frequency increases with age. Permanent teeth are affected more commonly than deciduous teeth In multirooted teeth one or more roots are involved. No sensitivity Can cause fusion of roots Radiographic features: There is thickening or blunting of the root. Lamina dura will follow the outline of teeth in normal periodontal ligament space Clinical significance: Sectioning of the tooth may be necessary during removal.

90. DEVELOPMENTAL DISTURBANCES IN STRUCTURE OF TEETH

91. Developmental disturbances in the structure of teeth Amelogenesis imperfecta Environmental enamel hypoplasia Dentinogenesis imperfecta Dentin dysplasia Regional odontodysplasia Dentin hypocalcification

92. Amelogenesis imperfecta Synonyms : Hereditary enamel dysplasia, Hereditary brown enamel, Hereditary brown opalescent teeth A structural defect of the tooth enamel with complex inheritance pattern Shafer, hine and levy textbook of oral pathology 9 th edition.

93. Etiology Dental enamel is a highly mineralized tissue with over 95% of its volume occupied by usually large, highly organized, hydroxyapatite crystals. The formation of this highly organized and unusual structure is thought to be rigorously controlled in ameloblasts through the interaction of a number of organic matrix molecules that include Enamelin Amelogenin ameloblastin Tuftelin Amelotin Enzymes such as kallikerin and Matrix metalloproteiases 20 (MMP20) Any mutations in these proteins can cause AI. Shafer, hine and levy textbook of oral pathology 9 th edition.

94. 3 basic types are Hypoplastic Hypocalcification Hypomaturation Witkop and Sauk listed the varieties of AI, divided according to whether the abnormality lay in a reduced amount of enamel ( hypoplasia ), deficient calcification ( hypocalcification ), or imperfect maturation of the enamel ( hypomaturation ), and also recognized the combined defects Shafer, hine and levy textbook of oral pathology 9 th edition.

95. Classification of Amelogenesis Imperfecta ( witkop and sauk )

96. Hypoplastic type Clinical and radiographic features : Inadequate deposition of enamel matrix Any matrix present will mineralize appropriately Absence of enamel thickness Open contact points Radiographically , a thin peripheral outline of radiopaque enamel Shafer, hine and levy textbook of oral pathology 9 th edition.

97. Hypoplastic amelogenesis imperfecta , generalized pitted pattern. Numerous pinpoint pits scattered across the surface of the teeth. The enamel between the pits is of normal thickness, hardness and coloration.

98. Hypomaturation type Clinical and radiographic features: The enamel can be pierced by an explorer point under firm pressure. It can be lost by chipping away from the underlying normal appearing dentin. Teeth are normal in shape, but exhibit a mottled, opaque white brown yellow discolouration. Enamel matrix is laid appropriately, there is a defect in maturation of enamel crystal structure Radiographically , radio density similar to dentin Snow capped pattern- exhibit a zone of white opaque enamel on the incisal or occlusal third of the crown. Shafer, hine and levy textbook of oral pathology 9 th edition.

99. Hypomaturation AI, snowcapped pattern. Dentition exhibiting zone of white opaque enamel in the incisal and occlusal one fourth of the enamel.

100. Hypomaturation AI : Dentition exhibiting mottled, opaque white enamel with scattered areas of brown discoloration

101. Hypocalcified type Clinical and radiographic features : The enamel is so soft that it can be removed by a prophylaxis instrument Yellow brown or orange on eruption, stained brown to black with time. Exhibits rapid calculus apposition. Occlusal surface more irregular Coronal enamel lost with function, except for the cervical portion which is mineralized better. Autosomal recessive- more severe. No significant mineralization Radiographically radio density of enamel and dentin are similar Shafer, hine and levy textbook of oral pathology 9 th edition.

102. Dentition exhibiting diffuse yellow-brown discoloration. The above picture shows numerous teeth with loss of coronal enamel except for the cervical portion.

103. Other features Both dentitions are affected In some cases teeth may appear normal, in others may be extremely unsightly. Color of the crown can vary from yellow to dark brown. Enamel might have numerous parallel vertical wrinkles or grooves. Open contact points Occlusal surfaces and incisal edges are frequently abraded. Shafer, hine and levy textbook of oral pathology 9 th edition.

104. Radiographic features The enamel may appear totally absent When present may appear as a thin layer, chiefly over the tips of the cusps and on the interproximal surfaces. In some cases calcification is so much affected that enamel and dentin seem to have the same radio density, making differentiation between the two difficult. Shafer, hine and levy textbook of oral pathology 9 th edition.

105. AAPD guidelines for management of AI Preventive care : Regular periodic examinations can identify teeth needing care as they erupt. Meticulous oral hygiene, calculus removal, and oral rinses can improve periodontal health. Fluoride applications and desensitizing agents may diminish tooth sensitivity. Restorative care: The appearance, quality, and amount of affected enamel and dentin will dictate the type of restorations necessary to achieve esthetic, masticatory , and functional health. If the enamel is hypocalcified , composite resin or porcelain veneers may be able to be retained with bonding. If the enamel or dentin cannot be bonded, full coverage restorations will be required. During the primary dentition, it is important to restore the teeth for adequate function and to maintain adequate arch parameters. Primary teeth may require composite or veneered anterior crowns with posterior full coverage steel or veneered crowns. American Academy of Pediatric Dentistry. Guideline on Oral Health Care/Dental Management of Heritable Dental Developmental Anomalies. The Reference Manual of Pediatric Dentistry. Chicago, Ill.: American Academy of Pediatric Dentistry; 2013:466-83

106. The prosthetic treatment may require veneers, full coverage crowns, implants, and fixed or removable prostheses. The fabrication of an occlusal splint is advocated to reestablish vertical dimension when full mouth rehabilitation is necessary. Behavior guidance, as well as the psychological health of the patient, will need to be addressed in each phase. Counseling for the child or adolescent and his/her family should be recommended when negative psychosocial consequences of the disorder are recognized. Due to extensive treatment needs, a patient may require sedation or general anesthesia for restorative care. American Academy of Pediatric Dentistry. Guideline on Oral Health Care/Dental Management of Heritable Dental Developmental Anomalies. The Reference Manual of Pediatric Dentistry. Chicago, Ill.: American Academy of Pediatric Dentistry; 2013:466-83

107. Treatment Treatment depends on the specific AI type and the character of the affected enamel. Treatments range from preventive care using sealants and bonding for esthetics to extensive removable and fixed prosthetic reconstruction. Therapy for hypoplastic AI types typically involves the use of bonding procedures to protect the malformed teeth from caries and improve esthetics . Hypoplastic teeth usually have reasonably well mineralized enamel, albeit thin / pitted making them suitable for restorative therapies involving bonding to the enamel. Composite resin or porcelain veneers can be bonded to the anterior teeth when the incisor shape, size and/ color requires modification. Shafer, hine and levy textbook of oral pathology 9 th edition.

108. The type which exhibits thin enamel ( hypocalcification-hypomaturation )- full coverage crown. Patterns without significant crown length: full dentures Less rapid hypoplastic tooth loss : aesthetics is the prime consideration – full crown, facial veneers. Resin crowns can be placed on permanent incisors soon after they begin to erupt during the mixed dentition ( about age 7-10yrs). As the gingival margins becomes exposed during continued tooth eruption the resins are easily modified by adding resin to the gingival margin of the tooth. Ultimately, porcelain fused to metal or other custom fabricated crowns can be placed on the dentition. This may be delayed until late adolescence or early adulthood when all the teeth are present, the teeth are fully erupted, and the gingival height around the teeth has stabilized. While costly, these types of restorations can allow even severely affected dentitions to be treated and achieve excellent function and esthetics . Shafer, hine and levy textbook of oral pathology 9 th edition.

109. The hypomaturation and hypocalcified AI types can be restored with conventional approaches if the enamel is not severely involved. If enamel is severely hypomineralized and of insufficient strength to retain bonded or intracoronal restorations, full coverage restorations should be placed. In cases of severely hypomineralized enamel, stainless steel crowns are indicated in the primary and early permanent dentitions. Shafer, hine and levy textbook of oral pathology 9 th edition.

110. Case reports Toupenay , S., Fournier, B.P., Manière , MC.  et al.   Amelogenesis imperfecta : therapeutic strategy from primary to permanent dentition across case reports.  BMC Oral Health   18 , 108 (2018). https://doi.org/10.1186/s12903-018-0554-y

111. Toupenay , S., Fournier, B.P., Manière , MC.  et al.   Amelogenesis imperfecta : therapeutic strategy from primary to permanent dentition across case reports.  BMC Oral Health   18 , 108 (2018). https://doi.org/10.1186/s12903-018-0554-y

112. Toupenay , S., Fournier, B.P., Manière , MC.  et al.   Amelogenesis imperfecta : therapeutic strategy from primary to permanent dentition across case reports.  BMC Oral Health   18 , 108 (2018). https://doi.org/10.1186/s12903-018-0554-y

113. Enamel hypoplasia Definition : incomplete or defective formation of organic enamel matrix of teeth Depending upon the severity of the condition, it is graded as mild, moderate and severe. Primary dentition usually shows the mild form whereas permanent dentition shows the severe form. Types: Type – I Hereditary- affects both dentition Type – II caused by environmental factors – only single tooth Clinical features : Mild cases few grooves, pits and fissures Severe rows of deep pits Most severe forms – considerable portion of enamel may be absent. Shafer, hine and levy textbook of oral pathology 9 th edition.

114. Etiological classification : 1. Hypoplasia due to local infection or trauma: Hypoplastic areas are commonly seen on the crowns of teeth resulting from infection or trauma to primary teeth. Hypoplasia resulting due to local infection is termed as Turners tooth or turners hypoplasia . Trauma to primary teeth may lead to interference in matrix formation or calcification of the developing permanent teeth, resulting in hypoplasia . 2. Hypoplasia due to nutritional deficiencies: Hypoplasia is commonly seen in individuals with vitamin A, C or D, calcium and phosphorous deficiencies. 3. Hypoplasia associated with allergies: The correlation between hypoplasia and allergic reactions was discovered by rattner and myers . Hypoplasia is commonly seen in children showing severe allergic reactions. 4. Hypoplasia due to radiation: The process of enamel matrix formation is adversely affected in children undergoing radiation therapy for malignancy. 5. Hypoplasia due to high fluoride intake : Excess consumption of fluoride can result in mottled enamel. The enamel shows white opaque or pitted areas, which vary in severity and extent according to the degree of fluorosis . Shafer, hine and levy textbook of oral pathology 9 th edition.

115. 6. Hypoplasia in association with neurologic defects : Enamel hypoplasia is commonly evident in children with low IQ scores and neurologic defects. There is a direct relationship between the defect and the time of brain injury. Thus, children who experience brain damage may also show hypoplastic changes of enamel. 7. Hypoplasia due to chronic lead poisoning : Mothers who have a history of lead poisoning can be affected as lead readily crosses the placenta. Pitting enamel hypoplasia is seen in these children. 8. Hypoplasia associated with congenital syphilis : Hutchinson’s triad has been observed in patients with the above disorder. The triad consists of 8 th nerve deafness, keratomalacia and enamel hypoplasia . 9. Hypoplasia associated with exanthematous diseases : For example, Scarlet fever. Shafer, hine and levy textbook of oral pathology 9 th edition.

116. Molar incisor hypomineralisation (MIH) It is a developmental defect due to environmental changes that affect the enamel leading to permanent damage of the 1 st permanent molars and incisors. This condition is also known as non-fluoride enamel opacities, internal enamel hypoplasia , non-endemic mottling of enamel, opaque spots, idiopathic enamel opacities, enamel opacities and idiopathic enamel hypomineralisation . The localized and asymmetrical presentation suggests disturbance in the amelogenesis process during the early maturation or late secretory phase. The most probable causes include: - environmental changes - severe malnutrition - maternal diabetes - systemic diseases - use of antibiotics - febrile illness - respiratory and infectious diseases Shafer, hine and levy textbook of oral pathology 9 th edition.

117. Here the hypomineralisation usually follows natural incremental lines of enamel, extending from the cusp to CEJ. The defect is mostly confined to the inner enamel while the outer enamel does not appear to be affected. Clinical features: Opacities in upper and lower incisors Enamel can be soft porous, resembling discoloured chalk. It may vary from white to yellow- brown with smooth surface and normal thickness in the molars.

118. Treatment Hypoplastic teeth are prone to caries. In cases of mild enamel hypoplasia , the small carious lesions can be restored with amalgam, resin or glass ionomer cement. Composite resin restorations can be done for anterior tooth restorations. Sensitivity of teeth is a common complaint. Topical fluoride application decreases the sensitivity. Severe enamel hypoplasia results in large areas of defective enamel and exposed dentin. Stainless steel crowns on posterior teeth can be given in cases of severe crown destruction. Restorative rehabilitation by means of microabrasion , composite resin restoration and bleaching can reproduce the natural tooth appearance. Shafer, hine and levy textbook of oral pathology 9 th edition.

119. Casaña -Ruiz, María Dolores et al. “Management of Hypoplastic or Hypomineralized Defects with Resin Infiltration at Pediatric Ages: Systematic Review.”  International journal of environmental research and public health  vol. 20,6 5201. 15 Mar. 2023, doi:10.3390/ijerph20065201

120. Dentinogenesis imperfecta Dentinogenesis imperfecta is an autosomal dominant condition affecting both deciduous and permanent teeth. Genetic alteration : DSPP-Chromosome 4 Encoding dentin phosphoprotein and dentin sialoprotein Affected teeth are gray to yellowish brown and have broad crowns with constriction of the cervical area resulting in tulip shape. Shafer, hine and levy textbook of oral pathology 9 th edition.

121. Classifications Oral and Maxillofacial Pathology, 2nd ed , Neville BW, Damm DD, Allen CM, Bouquot JE, Abnormalities of Teeth, page 94, Copyright WB Saunders Company, 2002.

122. Dentinogenesis imperfecta I The crowns of the deciduous and permanent teeth wear rapidly after eruption and multiple pulp exposure may occur. The dentin is amber and smooth. Radiograpgh of deciduous teeth shows large pulp chambers and root canals which reduces with age. The pulp spaces of the permanent teeth may be completely obliterated Shell teeth appearance. Shafer, hine and levy textbook of oral pathology 9 th edition.

123. Dentinogenesis imperfecta II Also known as opalescent dentin. Caused by mutation of DSPP gene. The teeth are blue gray or amber brown and opalescent the teeth have bulbous crowns, roots that are narrower than normal, pulp chambers and root canals that are smaller than normal or obliterated The enamel may split readily from the dentin when subjected to occlusal stress. Severe attrition of teeth Shafer, hine and levy textbook of oral pathology 9 th edition.

124. Histological features: Irregular tubules, with large areas of uncalcified matrix Tubules are larger in diameter Dentinal tubules in D.I are disoriented Physical and chemical features: Water content increased 60% Hardness- low Treatment : Full coverage crowns Overlay dentures placed on teeth covered with flouride releasing GIC Vertical dimension rebuilt- metal castings Newer composite combined with dentin bonding agent- occlusal wear Shafer, hine and levy textbook of oral pathology 9 th edition.

125. AAPD guidelines of management Preventive care : Early identification and preventive interventions are critical for individuals with DI in order to avoid the negative social and functional consequences of the disorder. Regular periodic examinations can identify teeth needing care as they erupt. Meticulous oral hygiene, calculus removal, and oral rinses can improve periodontal health. Fluoride applications and desensitizing agents may diminish tooth sensitivity. American Academy of Pediatric Dentistry. Guideline on Oral Health Care/Dental Management of Heritable Dental Developmental Anomalies. The Reference Manual of Pediatric Dentistry. Chicago, Ill.: American Academy of Pediatric Dentistry; 2013:466-83

126. Restorative care : Routine restorative techniques often can be used effectively to treat mild to moderate DI - In more severe cases with significant enamel fracturing and rapid dental wear, the treatment of choice is full coverage restorations in both the primary and permanent dentitions. Cases having severe loss of coronal tooth structure and vertical dimension maybe considered candidates for overdenture therapy . Overlay dentures placed on teeth that are covered with fluoride-releasing glass ionomer cement have been used with success. Bleaching has been reported to lighten the color of DI teeth with some success; however, because the discoloration is caused primarily by the underlying yellow-brown dentin, bleaching alone is unlikely to produce normal appearance in cases of significant discoloration. Different types of veneers can be used to improve the esthetics and mask the opalescent blue-gray discoloration of the anterior teeth.

127. Endodontic considerations: Some patients with dentinogenesis imperfecta will suffer from multiple periapical abscesses apparently resulting from pulpal strangulation secondary to pulpal obliteration or from pulp exposure due to extensive coronal wear. The potential for periapical abscesses is an indication for periodic radiographic surveys on individuals with DI. Because of pulpal obliteration, apical surgery may be required to maintain the abscessed teeth. Attempting to negotiate and instrument obliterated canals in DI teeth can result in lateral perforation due to the poorly mineralized dentin. Occlusion: Class III malocclussion with high incidences of posterior crossbites and openbites occur in DI Type I and should be evaluated. Multidisciplinary approaches are essential in addressing the complex needs of the individuals affected with DI.

128. Casaña -Ruiz MD, Frechina N, Estrela F, Catalá -Pizarro M. Dentinogenesis imperfecta : case report with nanoceramic resin crowns restorative treatment. Journal of Clinical Pediatric Dentistry. 2024 Mar 1;48(2). Case report This clinical case report describes the oral rehabilitation procedure in a 12-year-old patient with dentinogenesis imperfecta type II using nanoceramic resin crowns fabricated with Computer-Aided Design/Computer-Aided Manufacturing (CAD/CAM) technology and the patient’s progression over eight years.

129. Casaña -Ruiz MD, Frechina N, Estrela F, Catalá -Pizarro M. Dentinogenesis imperfecta : case report with nanoceramic resin crowns restorative treatment. Journal of Clinical Pediatric Dentistry. 2024 Mar 1;48(2).

130. Casaña -Ruiz MD, Frechina N, Estrela F, Catalá -Pizarro M. Dentinogenesis imperfecta : case report with nanoceramic resin crowns restorative treatment. Journal of Clinical Pediatric Dentistry. 2024 Mar 1;48(2).

131. Casaña -Ruiz MD, Frechina N, Estrela F, Catalá -Pizarro M. Dentinogenesis imperfecta : case report with nanoceramic resin crowns restorative treatment. Journal of Clinical Pediatric Dentistry. 2024 Mar 1;48(2).

132. Dentin dysplasia/ rootless teeth Dentin dysplasia is a rare hereditary disturbance inherited as an autosomal dominant trait. Atypical dentin formation with abnormal pulp morphology Systemic DS. Associated with dentin dysplasia Clacinosis universalis Rheumatoid arthritis and vitaminosis Sclerotic bone and skeletal abnormalities Tumor calcinosis Shields and his associates separated it into – Type 1 dentin dysplasia Type 2 anomalous dysplasia of dentin Witkop referred as – Radicular type 1 Coronal type 2

133. Type 1 ( Radicular ) Slight amber translucency Normal appearing crowns No or rudimentary root development(rootless teeth) Exfoliated prematurely or after only minor trauma Radiographically : Deciduous – pulp completely obliterated Permanent – crescent shaped. Type 1 ( coronal ) Yellow brown or bluish gray opalescent Clinical appearance of permanent dentition is normal Radiographically : Deciduous- pulp chamber obliterated Permanent- thistle tube shaped or flame shaped coronal pulp chambers Thread like root canals. Shafer, hine and levy textbook of oral pathology 9 th edition.

134. Histological features Type -1 ( radicular ) – lava flowing around boulders Type -2 ( coronal )- Deciduous : amorphous and atubular dentin in radicular portion Permanent : multiple pulp stones or denticles Shafer, hine and levy textbook of oral pathology 9 th edition.

135. Treatment : Preventive care Meticulous oral hygiene There is no treatment for the disease, its prognosis depends on the occurence of periapical lesions necessitating tooth extraction as well as on the exfoliation of teeth due to increased mobility. Periapical inflammatory lesions : therapeutic choice guided by root lengths Shafer, hine and levy textbook of oral pathology 9 th edition.

136. Case report Krug, R., Volland , J., Reich, S.  et al.  Guided endodontic treatment of multiple teeth with dentin dysplasia: a case report.  Head Face Med   16 , 27 (2020). A 12-year old female with radicular dentin dysplasia type I (DD-1) presented for endodontic treatment. Radiography revealed PCC in all teeth and apical radiolucency in seven teeth (12, 15, 26, 31, 32, 36 and 46). Tooth 36 had the most acute symptoms and was thus treated first by conventional access cavity preparation and root canal detection. Despite meticulous technique, the distal and mesiolingual canals were perforated. The perforations were immediately repaired with mineral trioxide aggregate, and the decision was made to switch to guided endodontic treatment for the remaining 6 teeth. CBCT and intraoral surface scans were acquired and matched using coDiagnostix planning software (Dental Wings Inc.), the respective drill positions for root canal location were determined, and templates were virtually designed and 3D-printed. The template was positioned on the respective tooth, and a customized drill was used to penetrate the calcified part of the root canal and perform minimally invasive access cavity preparation up to the apical region. All root canals were rapidly and successfully located with the templates. At 1-year follow-up, clear signs of apical healing were present in all treated teeth.

137. Krug, R., Volland , J., Reich, S.  et al.  Guided endodontic treatment of multiple teeth with dentin dysplasia: a case report.  Head Face Med   16 , 27 (2020).

138. Regional odontodysplasia / Ghost teeth Odontogenic dysplasia, Odontogenic imperfecta Etiology : Abnormal migration of neural crest cells Latent virus Local circulatory deficiency Local trauma or infection Hyperpyrexia Malnutrition Medication Radiation therapy Alteration in vascular supply

139. Clinical features: Teeth appear yellow to brownish Usually small with asymmetrical morphology They exhibit either a delay or a total failure in eruption Tooth is friable and susceptible to caries and fractures Few cases with ipsilateral , contralateral and bilateral involvement affecting the jaw bones and crossing the midline is also reported. Radiographic features: Radiographs show marked reduction in radiodensity so that the teeth assume a pale whispy “ghost” appearance. Both enamel and dentin appear very thin and the pulp chamber is exceedingly large. Histological features: Most characteristic feature of the disease are the marked reduction in the amount of dentin Widening of predentin layer Presence of large areas of interglobular dentin and an irregular tubular pattern of dentin. Characteristically, the reduced enamel epithelium and follicular tissue around non-erupted teeth shows many irregular bodies( enameloid conglomerates)

140. Treatment: Because of the poor cosmetic appearance of these teeth, extraction with restoration by a prosthetic appliance is usually indicated.

141. Dentin hypocalcification - Normal Dentin Formation : Dentin is calcified by depositing calcium salts in the organic matrix, forming globules that eventually unite into a homogeneous structure. - Dentin Hypocalcification : In dentinal hypocalcification , there is a failure of these globules to unite, leaving uncalcified matrix areas known as interglobular dentin. - Detection : Globular dentin is easily detected in both ground sections and decalcified histologic sections of teeth, but it does not alter the clinical appearance. - Softness Hypothesis : Some clinicians believe they can detect globular dentin by its softness, though this remains unproven. It's logical that hypocalcified dentin might be softer than well-calcified dentin. - Causes : Causes of dentin hypocalcification are similar to those of environmental enamel hypocalcification and enamel hypoplasia . Factors like parathyroid deficiency or rickets can interfere with normal calcification, leading to hypocalcification .

142. Treatment Treatment options for dentin hypocalcification focus on managing the symptoms and protecting the affected teeth since there is no way to reverse the condition itself. Here are some common approaches: 1. Fluoride Treatment : Application of fluoride can help to strengthen the remaining enamel and dentin, potentially reducing sensitivity and protecting against further decay. 2. Dental Sealants : Sealants can be applied to the affected areas to protect the hypocalcified dentin from wear and decay. 3. Restorative Treatments : Depending on the severity, restorative options like composite resins, crowns, or veneers may be used to restore the function and appearance of affected teeth. 4. Desensitizing Agents : These can be applied to reduce sensitivity in teeth with hypocalcified dentin. 5. Good Oral Hygiene : Maintaining good oral hygiene practices is essential to prevent decay and other complications in affected teeth. 6. Regular Dental Check-ups : Regular monitoring by a dentist ensures that any signs of decay or damage can be addressed promptly. 7. Dietary Adjustments : Avoiding acidic foods and drinks can help reduce the risk of further enamel and dentin damage. 8. Education and Counseling : Patients can benefit from education about the condition, helping them understand the importance of oral care and preventive measures.

143. Developmental disturbances in growth ( eruption ) of teeth

144. Developmental disturbances in growth ( eruption ) of teeth Premature eruption Delayed eruption Eruption sequestrum Multiple unerupted teeth Retained deciduous teeth Embedded and impacted teeth Ankylosed and deciduous teeth

145. Premature eruption natal teeth neonatal teeth described as hornified epithelial structures without roots, occurring on the gingiva over the crest of the ridge They are poorly, developed small, conical, yellowish with hypoplastic enamel, dentin with total failure of development of roots. Infants occasionally are born with structures which appear to be erupted teeth, usually in the mandibular incisor area. Shafer’s textbook of oral pathology, 7 TH edition

146. Etiology : Hereditary factors or an underlying syndrome could also predispose to its occurrence hypovitaminosis hormonal stimulation trauma Shafer’s textbook of oral pathology, 7 TH edition Jain S, Rathi N, Thosar N, Baliga S. Management of Neo-Natal Teeth: A Case Report.-2018

147. Natal teeth : at the time of birth Should be distinguished from true deciduous teeth. it commonly projects above the crest of the ridge, is white in color and is packed within keratin, so that it appears ‘ hornified ’ and can be easily removed. Neo natal : arising with in first 30 days of life.

148. Complications A major complication from natal/neonatal teeth is ulceration on the ventral surface of the tongue caused by tooth’s sharp incisal edge. This condition is also known as Riga fede disease or syndrome. Possibility of swallowing or aspiration Injury to mothers breast and inconvenience during suckling. The consequences seen with teeth include carious lesions, pulp polyp or premature eruption of successor teeth.

149. Management of natal and neonatal teeth Smoothing off incisal edges of lower incisors. Modifying feeding behavior or feeding device. Extraction should be indicated only if the teeth is highly mobile and if there is interference with feeding.

150. it is safer to wait until a child is 10 days old before extracting the tooth. The waiting period before performing tooth extraction is to wait for the intestinal commensal flora to become established and to produce vitamin K which is essential for the production of prothrombin in the liver. It is advisable to evaluate the need for administration of vitamin K by a paediatrician . Vitamin K (0.5–1.0 mg) is administered intramuscularly to the baby as part of immediate medical care to prevent haemorrhagic disease of the newborn. Jain S, Rathi N, Thosar N, Baliga S. Management of Neo-Natal Teeth: A Case Report.-2018 Precautions should be taken before extraction are

151. Jain S, Rathi N, Thosar N, Baliga S. Management of Neo-Natal Teeth: A Case Report.-2018

152. Eruption sequestrum Anomaly associated with tooth eruption in children. Described by starkey and shafer . It is a tiny, irregular spicule of bone overlying the crown of an erupting permanent molar, found just prior to or immediately following the emergence of the tip of the cusps through the oral mucosa. Etiology : As the molar teeth erupt through the bone, they can separate a small osseous fragment from the surrounding bone similar to a cork screw. In most cases the fragment undergoes complete resorption before eruption. If the bony spicule is large or the eruption is rapid, complete resorption cannot occur and hence, it is observed.

153. Clinical features: The child may complain of slight soreness in the area during function. The spicule directly overlies the central occlusal fossa but is within the soft tissue. It may be seen lying in a tiny depression over the crest of the ridge. As the tooth erupts, the fragment of bone completely sequesters through the mucosa and is lost. Radiographic features: It can be recognized even before the tooth eruption. Seen as a tiny, irregular opacity overlying the central occlusal fossa but separated from the tooth itself.

154. Clinical significance and treatment: Child may complain of slight soreness in the area Causes of Soreness : Soreness may be caused by compression of the soft tissue over the spicule during eating, just before it breaks through the mucosa. Soreness can also occur due to the movement of the spicule in the soft-tissue crypt during mastication and after it erupts through the mucosa. Treatment : No treatment is necessary as the condition typically resolves on its own.

155. Case report Roza AL, de Abreu Brandi TC, Bezerra KT, Abrahão AC, Agostini M, de Andrade BA, Vargas PA, Romañach MJ. Eruption sequestrum : an inflamed odontogenic hamartoma . Oral and Maxillofacial Surgery. 2020 Sep;24:363-8.

156. Roza AL, de Abreu Brandi TC, Bezerra KT, Abrahão AC, Agostini M, de Andrade BA, Vargas PA, Romañach MJ. Eruption sequestrum : an inflamed odontogenic hamartoma . Oral and Maxillofacial Surgery. 2020 Sep;24:363-8.

157. The patient underwent an excisional biopsy under local anesthesia with the clinical hypothesis of ES, and gross examination revealed a hardened whitish fragment measuring 0.5 cm surrounded by the gingival mucosa. Microscopically, odontogenic epithelial cords associated with small calcified, concentric basophilic and dentinoid like structures were observed in the presence of chronic inflammatory infiltrate and small blood vessels were observed in the adjacent connective tissue. The clinical, radiographic, and microscopic findings supported a final diagnosis of an inflamed odontogenic hamartoma . Roza AL, de Abreu Brandi TC, Bezerra KT, Abrahão AC, Agostini M, de Andrade BA, Vargas PA, Romañach MJ. Eruption sequestrum : an inflamed odontogenic hamartoma . Oral and Maxillofacial Surgery. 2020 Sep;24:363-8.

158. Retained deciduous teeth - Retention of Deciduous Teeth: Deciduous teeth may fail to exfoliate and be retained beyond the normal shedding time. - Functionality: Retained deciduous teeth can function if the crown, root, and periodontal structures remain intact. - Common Retained Teeth: - Most common: mandibular second molar. - Followed by: maxillary deciduous canine and mandibular canine. - Possible Causes : - Absence of successor teeth. - Impaction or translocation of permanent teeth. - Presence of pathological lesions (e.g., cysts, tumors, odontoma ). - Microdontia of permanent teeth. Systemic factors, such as syndromes, metabolic disorders, and hormonal disorders, are additional causes of over-retained teeth.

159. - Permanent Tooth Eruption and Deciduous Tooth Resorption : Permanent tooth eruption causes resorption of the roots of deciduous teeth. -Occasional Retention: Sometimes, the roots of a deciduous tooth are retained even after the crown exfoliates. - Attrition and Infraocclusion : Retained deciduous teeth often undergo occlusal surface attrition and become infraoccluded , especially in cases of ankylosed deciduous molars (submerged teeth). - Effect on Neighboring Teeth: In ankylosed cases, neighboring permanent teeth continue to erupt normally, increasing their crown length relative to the retained tooth. - Management : - If a successor tooth is present, extraction followed by orthodontic treatment is recommended. - If the permanent tooth is missing and the retained deciduous tooth is intact, it should be preserved for as long as possible.

160. The patient presented with nine retained deciduous teeth in the mandibular arch. These retained primary teeth had persisted beyond the expected age, and their presence was causing malocclusion and aesthetic concerns. Treatment planning involved a multidisciplinary approach. Orthodontic goals focused on aligning the permanent dentition while addressing the retained deciduous teeth. Agarwal N, Pallavi Daigavane . Multiple Over-retained Deciduous Teeth: A Rare Case Report. Journal of Clinical and Diagnostic Research. 2023 Jan 1; ‌

161. Agarwal N, Pallavi Daigavane . Multiple Over-retained Deciduous Teeth: A Rare Case Report. Journal of Clinical and Diagnostic Research. 2023 Jan 1; ‌

162. Multiple unerupted teeth - Condition: Rare condition with permanently delayed tooth eruption. - Symptoms: - May involve retained deciduous teeth. - More commonly, deciduous teeth are shed, but permanent teeth fail to erupt. - Terminology: The term " pseudoanodontia " is used when permanent teeth fail to erupt. - Clinical Findings: Clinical and radiographic exams often show normal jaws and teeth, but there is a lack of eruptive force. - Treatment: - If due to endocrine dysfunction, proper treatment may lead to tooth eruption. - No known therapy if associated with cleidocranial dysplasia.

163. Deep, Aman & Thakur , Seema & Jayam , Cheranjeevi . (2021). An interesting case of unilateral multiple impacted unerupted teeth in a young adolescent child: A case report and discussion. Journal of Natural Science, Biology and Medicine. 12. 256. 10.4103/jnsbm.jnsbm_12_21.

164. Treatment objective The primary treatment objective here would be exposure of impacted teeth in lower left quadrant and possible enucleation of malformed primary teeth in the premolar region, and also, the orthodontic treatment plan would necessitate fixed orthodontic therapy in coordination with oral surgery to expose and bond the impacted teeth. The secondary objective includes extraction of 53,63,85 to facilitate the eruption of permanent counterpart, leveling and alignment of teeth, midline correction, and establishing Angle’s Class I molar relationship. Other more extensive treatment alternatives include extraction of all lower left impacted teeth, and since there is cortical bone expansion, construction of partial denture would be difficult, so using iliac grafts, alveolar ridge construction needs to be done and removable partial denture can be given. Implant‑retained prosthesis is another treatment alternative that can be dwelled upon. This treatment alternative remains to be the preferred option as more often in the literature, however, since the patient is still young, orthodontic approach should be the preferred treatment line as it facilitates the patient’s natural dentition and saves him from future cost and long‑term replacement restorations. Deep, Aman & Thakur , Seema & Jayam , Cheranjeevi . (2021). An interesting case of unilateral multiple impacted unerupted teeth in a young adolescent child: A case report and discussion. Journal of Natural Science, Biology and Medicine. 12. 256. 10.4103/jnsbm.jnsbm_12_21.

165. Delayed eruption Failure of tooth to erupt within a specified time is known as delayed eruption. Most cases of apparent delay are within the normal range. Reassurance to the parents and regular review is essential Delay of upto 6 months from the date of eruption is usually considered normal. Contralateral teeth usually erupt together.

166. Possible causes of delayed eruption Generalized delayed eruption Ectodermal dysplasia Downs syndrome Osteoporosis Cleidocranial dysplasia Hypopitutarism hypothyroidism Localized delay in eruption Effects of deciduous teeth Retained deciduous teeth Ankylosis of deciduous teeth Gingival hyperplasia Hereditary Drug induced ( antiepileptic/ ca channel blocker/ cyclosporin ) Scar formation after surgical removal of unerupted supernumerary tooth Very early loss of deciduous teeth Obstruction in eruption pathway Cyst eg : dentigerous cyst Odontome Supernumerary teeth Dilaceration trauma to primary dentition

167. Treatment Generalized delayed eruption: No local treatment Regular recall Wait and see signs of eruption Intervene when necessary Local causes Removal of affected teeth Eg : extraction of retained deciduous teeth Erupted supernumerary teeth Simple extraction if erupted But before extraction check with X-ray for unerupted supernumerary teeth Unerupted or burried supernumerary teeth Surgical removal Allow the inciosr to erupt

168. Eruptive potential :(+) Incomplete root formation Close observation for eruption of uneruptive tooth Eruptive potential : (-) Complete root formation Orthodontic extrusion

169.   An 8-year-old male presented to the Pediatric Dentistry Clinic, accompanied by his father, with the main concern of delayed exfoliation of the maxillary left primary central incisor (#61). The patient’s medical history showed no remarkable findings. The dental history revealed that there was a history of TDI of the primary maxillary incisors when the child was two years old, including intrusion of the upper left primary central incisor (#61). The parents did not seek any dental treatment at that time. Alfarraj , Jawza H et al. “Management of Delayed Eruption in Permanent Incisor Following Intrusion Injury of Primary Dentition: A Case Report.”  International medical case reports journal  vol. 15 463-467. 31 Aug. 2022, doi:10.2147/IMCRJ.S380096

170. Ankylosed deciduous teeth Also called submerged teeth, infraocclusion , secondary retention, submergence, reimpaction and reinclusion . Definition : "Submerged" teeth are deciduous teeth, typically mandibular second molars, that have undergone root resorption and become ankylosed to the bone. Effect on Exfoliation : Ankylosis prevents these teeth from exfoliating and being replaced by permanent teeth. Appearance : After adjacent permanent teeth erupt, the ankylosed tooth seems to be submerged below the occlusal level. Explanation : This is due to continued growth of the alveolar process and the shorter crown height of the deciduous tooth compared to adjacent permanent teeth, altering the perceived occlusion level without changing the actual position of the deciduous tooth.

171. The diagnosis of ankylosis of a tooth is usually suspected clinically and confirmed by radiographic examination. The affected teeth lack mobility even though root resorption is far advanced. Upon percussion, an ankylosed tooth imparts a characteristic solid sound in contrast to the dull, cushioned sound of a normal tooth. Radiographically , at least partial absence of the periodontal ligament is seen, with areas of apparent blending between the tooth root and bone. The process is basically one of resorptions of tooth substance and bony repair with the result that the tooth is locked in bone. The cause of ankylosis is not known, although in some cases trauma, infection, disturbed local metabolism or a genetic influence has been considered an important etiologic factor. A patient who has had one or two ankylosed teeth is very likely to have other teeth ankylosed over a period of time. This condition is usually treated by the surgical removal of the ankylosed tooth to prevent the development of a malocclusion, a local periodontal disturbance or dental caries.

172. Embedded and impacted teeth Embedded teeth are individual teeth which are unerupted usually because of a lack of eruptive force. Impacted teeth are prevented from eruption by some physical barrier in the eruption path like, Lack of space – crowding, premature loss of deciduous teeth rotation of tooth buds. Trauma Cysts and tumors Systemic diseases like osteoporosis, ectodermal dysplasia, rickets and cretenism Any tooth may be impacted- usually mandibular third molars(22%), maxillary third molars(18%) and maxillary cuspids ( 0.9%), premolars and supernumerary teeth. Mandibular teeth are more severely impacted than maxillary teeth.

173. Evidence-based research supports the removal of third molars when pathology (e.g., cysts or tumors, caries, infection, pericoronitis , periodontal disease, detrimental changes of adjacent teeth or bone) is associated and/or the tooth is malpositioned or nonfunctional (i.e., an unopposed tooth). There is no evidence to support or refute the prophylactic removal of disease-free impacted third molars. American Academy of Pediatric Dentistry. Management considerations for pediatric oral surgery and oral pathology. The Reference Manual of Pediatric Dentistry. Chicago, Ill.: American Academy of Pediatric Dentistry; 2023:527-36.

174. Impacted maxillary cuspids also assume a variety of positions ranging from horizontal to vertical . In horizontally impacted cuspids the crown usually points in an anterior direction and may impinge on the roots of any of the incisors or premolars. The horizontal tooth may lie either labial or lingual to the associated teeth. The vertically impacted cuspid is usually situated between the roots of the lateral incisor and first premolar and is prevented from eruption simply by lack of space. When the cusp tip of the permanent canine is just mesial to or overlaying the distal half of the long axis of the root of the permanent lateral incisor, canine palatal impaction usually occurs. Extraction of the primary canines is the treatment of choice to correct palatally displaced canines or to prevent resorption of adjacent teeth. If no improvement in canine position occurs in a year, surgical and/or orthodontic treatment were suggested. American Academy of Pediatric Dentistry. Management considerations for pediatric oral surgery and oral pathology. The Reference Manual of Pediatric Dentistry. Chicago, Ill.: American Academy of Pediatric Dentistry; 2023:527-36.

175. Conclusion Careful examination and treatment planning are required in case of developmental disturbances. Clinicians should be aware that if one disturbance is present, other disturbances might also be present. Variations are seen in developmental dental disturbances and no two disturbances of the same types are identical. Early detection and diagnosis of dental disturbances are essential steps in evaluation and treatment planning. The dentist should evaluate dental disturbances the moment that they begin to interfere in the normal developmental pattern of occlusion. Then intervention should take place as soon as possible to evade malocclusion. Knowledge of developmental dental anomaly allows clinician to early diagnosis and manages these conditions appropriately with predictable clinical outcomes.