Third molar surgery

Maxillary and Mandibular Third Molar Impaction

1. THIRD MOLAR SURGERY DR JACOB JOHN PLACKAL RESIDENT,KVGDC

2. Hey! U came to the right place  GO THROUGH THIS AND HELP YOURSELF. DISCLAIMER: SOME OF THE SLIDES BELONG TO THE BEAUTIFUL PEOPLE WHO WERE KIND ENOUGH TO UPLOAD IT HERE.

3. CONTENTS Introduction Definition Theories of impaction Clinical & radiological assessment Classification Etiology Indications and contraindications Frequency Surgical anatomy Management Complications Recent advances

4. Historical background on the criteria for removal of third molar In 1979, a consensus development conference practicing dentists and scientists, on third molar removal was sponsored by national institute of health, USA. J oral surgery…vol38,march 1980

5. INTRODUCTION The third molar has been the most widely discussed tooth in the dental literature, and the debatable question “….. to extract or not to extract ” seems set to run into the next century. - Faiez N. Hattab , JOMS, 57: 389-391 (1999)

6. DEFINITION The term impaction is of latin origin from the term “ IMPACTUS ” used to designate an organ or structure which because of an abnormal mechanical condition has been prevented from assuming its normal position. Rounds (1962) :- “The condition in which a tooth is embedded in the alveolus so that its further eruption is prevented.”

7. Alling :- A n impacted tooth is a tooth that is completely / partially unerupted at its chronological age and is positioned against a physical barrier, such as another tooth, bone / soft tissue, so that its further eruption is unlikely described according to its anatomic position.

8. WHO :- An impacted tooth is the one that is unable to fully erupt in its normal functional occlusion / location by its expected age of eruption, because it is blocked by overlying soft tissue or bone or another tooth.

9. Causes of impaction Berger (1939) classified causes of impaction in two major Categories : Local causes Systemic causes

10. Local CAUSES Lack of space due to underdeveloped jaw. Long retention of primary teeth. Premature loss of primary teeth. Irregularity in position and pressure of an adjacent teeth. The density of overlying and surrounding bone Long continued chronic inflammation with resultant increase in density of the overlying mucous membrane. Acquired diseases such as necrosis due to infection and abscess. Inflammatory changes in the bone due to exanthematous disease in children. BERGER

11. SYSTEMIC CAUSES: A. Prenatal cause 1. Heredity 2. Miscegenation B . Postnatal cause (condition which may interfere with the development of child ) 1. Rickets 2. Anemia 3. Congenital syphilis 4. Tuberculosis 5. Endocrinal dysfunctions 6. Malnutrition C. Rare conditions 1. Cleidocranial dysostosis 2. Oxycephaly ( “ steeple head” ) 3. Progeria 4. Achondroplasia 5. Cleft palate

12. THEORIES OF IMPACTION By Durbeck Mendelian theory Phylogenic theory Orthodontic theory Endocrinal theory P athological theory

13. THE MENDELIAN THEORY Heredity is the most common etiologic factor in impaction. The transmission of small jaws from one parent and large teeth from the other would likely result in insufficient space for the teeth and instances of impaction. THE PHYLOGENIC THEORY Over centuries maxilla and mandible have decreased in size leaving insufficient room for 3rd molars. Congenitally missing 3rd molars in some individuals supports the view that the 3rd molar is a vestigial organ without current purpose or function.

14. The Endocrine theory Endocrinal disorders of thyroid, parathyroid, pituitary glands cause primary retention of the teeth. This is due to lack of osteoclastic activity which does not provide resorption of the bone overlying the developing tooth. Pathological theory Chronic infections affecting an individual may bring the condensation of osseous tissue further preventing the growth and development of the jaws.

15. The Orthodontic theory The normal growth of the jaw and the movement of teeth are in a forward direction, anything that interferences with such a development causes impaction. Forward movement is usually retarded by dense bone that can be produced by many pathologic conditions including acute infection, severe trauma, malocclusion, local inflammation of the periodontal membrane.

16. Assessment of impaction Preoperative assessment Clinical assessment General Local Radiological assessment

17. Factors to be kept in mind Extremes of age >25yrs risk of complications ( J Oral Maxillofac Surg 2007; 65: 1977-1983) Compromised medical status Excessive risk of damage to adjacent vital structures Availability of space Uncontrolled active pericoronal infection Questionable Status of future of Second molar

18. Clinical assessment General assessment Age General examination Medical risk

19. Factors to be considered in clinical assessment Complaint : pain, exclude other causes such as TMJ disorder, pulpitis/ abscess of other teeth. Previous medical history. Dental history: difficult extractions, postoperative infection, bleeding, etc. Extra-oral features: facial form, lymphadenopathy, lower lip is tested for paresthesia , swelling.

20. Local assessment Intra oral examination Mouth opening Size of tongue Extensibility of lips and cheeks Status of dentition Lymph nodes Assessment of impacted teeth in particular

21. Assessment of impacted teeth Crown visible ? Position and occlusal relation of opposing tooth Distal of second molar for pocket formation External oblique ridge Distance between distal surface of second molar and anterior border of ramus Condition of soft tissue

22. Radiographic assessment Radiographic views Intraoral periapical Orthopantamograph Occlusal Linear cross sectional tomography A diagnostic technique for determining the buccolingual relationship of impacted mandibular third molar and inferior alveolar neurovascular bundle Modified linear cross sectional tomography

23. Interpretation Of The Standardized Intraoral Radiograph

24. Access Ease of access to the site of operation may be determined by noting the inclination of the radio-opaque line cast by the external oblique ridge. If this line is vertical access is poor, whilst if it is horizontal access is excellent.

25. Root morphology The fused, conical roots are easier to remove than widely separate roots. Severely curved or dilacerated roots are more difficult to remove than straight or slightly curved roots. The direction of the tooth root curvature is also important The total width of the roots in mesiodistal direction should be compared with the width of the tooth at the cervical line. If the width is greater, the extraction will be more difficult.

26. Optimal time for removal of an impacted teeth is when the root is 1/3 to 2/3 formed. In this case roots are blunt and almost never fracture. If the root development is insufficient, the tooth is more difficulty to remove, because it tends to roll in its crypt like a ball in socket, which prevent easy elevation.

27. Size of follicular sac If the follicular size is wide, much less bone must be removed. Young patient are more likely to have large follicle. The narrow or nonexistent follicular space require creation of space, which increases both difficulty of procedure and the time require to remove the tooth.

28. Density of surrounding bone Patients who are 18 years of age or younger have bone densities favorable for tooth removal. The bone is less dense, is more likely to pliable, and expands and bends somewhat which allows the socket to be expanded by elevators or tooth itself. Patients who are older than age 25 have denser bone and thus decreased flexibility and ability to expand.

29. Shape of crown The teeth with large square crowns and prominent cusps are more difficult to remove then teeth with small conical crowns and flat cusps.

30. Crown and cusps are of especial importance when the ‘line of withdrawal’ of third molar is completely obstructed. It is characterized by the cusps of the third molars superimposed upon the distal surface of the second molar in the standard radiograph. The sectioning of the impacted tooth require to avoid damage or displacement of 2 nd molar from the socket.

31. Radiological prediction of inferior alveolar nerve injury According to J. P. Rood, B. A. A. Nooraldeen shehab , Diversion of mandibular canal Darkening of root Interruption of white lines Narrowing of roots Deflection of roots Narrowing of mandibular canal Dark and bifid root Br Jr of Oral and Maxillofacial Surgery 1990; 28: 20-25 J Oral Maxillofac Surg 2003; 61: 417- 421 J Oral Maxillofac Surg 2005; 63: 3-7

32. CORRELATION BETWEEN RADIOGRAPHIC SIGNS OF THIRD MOLAR PROXIMITY WITH INFERIOR ALVEOLAR NERVE AND POSTOPERATIVE OCCURRENCE OF NEUROSENSORY DISORDERS. A PROSPECTIVE, DOUBLE-BLIND STUDY 1 (Fabio et al) Acta cir. Bras. Vol.28 no.3 são paulo mar. 2013 There is no positive correlation between presence of radiographic signs of 3ms with IAN proximity and postoperative neurosensory disorders occurrence.

33. POSITION OF ROOT TO INFERIOR ALVEOLAR CANAL

34. Panoramic radiographic findings as predictors of mandibular nerve exposure following third molar extraction: Digital versus conventional radiographic techniques Oral Surg Oral Med Oral Pathol Oral Radiol Endod 2009;107: e36-e40) The imaging technique does not modify the relationship between high-risk panoramic radiographic signs and MN exposure.

35. Localization of impacted third molar using radiographs Periapical x-rays- frank’s tube shift technique Vertical tube shift technique For separating horizontally oriented objects For determining bucco -lingual position of third molar apices that super impose the mandibular canal

36. Clark’s horizontal tube shift For separating superimposed objects with vertical long axis For buccal / lingual localization of impacted third molar from roots of erupted teeth

37. Indications for therapy for third molars Pericoronitis prevention or treatment Management of unexplained pain Prevention of caries Root resorption of adjacent teeth Orthodontic considerations Teeth under dental prosthesis Preparation for orthognathic surgery Prevention of odontogenic cysts and tumours Prevention of jaw fracture

38. Pericoronitis- Prevention or Treatment Usually mandibular – partially erupt Microbes : peptostreptococcus , fusobacterium , and bacteroides ( porphyromonas ) Initial treatment : I. D ébridement Ii. Disinfection with irrigation solution (hydrogen peroxide or chlorhexidine) Iii. Surgical management – extract opposing max 3 rd molar. Iv. Severe cases with systemic effect – antibiotic Recurrent – removal of involved tooth

39. Prevention of Dental Disease DISTAL CERVICAL CARIES is a late phenomenon and has been reported only in association with impacted third molars. The early or prophylactic removal of a partially erupted mesio -angular third molar could prevent distal cervical caries forming in the mandibular second molar. Distal cervical caries in the mandibular second molar: An indication for the prophylactic removal of the third molar? Louis W. McArdle∗, Tara F. Renton British Journal of Oral and Maxillofacial Surgery 44 (2005) 42–45

40. Orthodontic Considerations Obstruction of orthodontic treatment Crowding of mandibular incisors Interference with orthognathic surgery

41. Prevention of Odontogenic Cysts and Tumors Follicular sac  cystic degeneration  dentigerous cyst  odontogenic tumor (rare)

42. Root Resorption of Adjacent Teeth Misaligned erupting teeth may resorb the roots of adjacent teeth just like succedaneous teeth resorb the roots of primary teeth during normal eruption. Most cases - adjacent tooth recalcified (deposition of a cementum over the resorbed area) & formation of 2 o dentin. If severe resorption & the mandibular 3 rd molar displaces significantly into the roots of the second molar  remove.

43. Teeth under Dental Prostheses Removable tissue borne prosthesis – is constructed on a ridge where an impacted tooth is covered by only soft tissue or 1 or 2 mm of bone  overlying bone resorbed, mucosa perforate & the area become painful and inflamed. So -- --> extract! In older patients with tooth- or implant-borne fixed prostheses asymptomatic deeply impacted teeth can be safely left in place.

44. Prevention of Jaw Fracture Patients engage in contact sports (football, rugby, martial arts) & noncontact sports (basketball)  remove to prevent jaw fracture An impacted third molar - resistance to fracture in mandible  common site for fracture Increased complications in the treatment of the fracture. Do pathologies associated with impacted lower third molars justify prophylactic removal? A critical review of the literature. Oral Surg Oral Med Oral Pathol Oral Radiol Endod 2006;102:448-52 States that risk of condylar fractures is more in patients without impacted lower third molar. Condylar fractures are comparatively difficult to treat as compared to angle fracture. Thus, risk of angle fractures should not be considered as an indication.

45. Management of Unexplained Pain Jaw pain in the area of an impacted third molar but no clinical or radiographic signs of pathology. The surgeon must make sure that all other sources of pain are ruled out before suggesting surgical removal of the third molar. Patient must be informed that removal of the third molar may not relieve the pain completely

46. Contraindication Extremes of age Compromised medical status. Possible excessive damage to adjacent structures. 3m would be expected to erupt successfully& have a functional role in dentition. No h/o or e/o pertinent local/systemic pathology. Prosthetic considerations : where used as an abutment for fpd . Socioeconomic reason.

47. Frequency of Impaction Mandibular 3 rd molar Maxillary 3 rd molar Maxillary canine Mandibular pre-molar Mandibular canines Maxillary premolars Maxillary lateral incisors Maxillary central incisors

48. Mandibular third Molar

49. Order of frequency of mandibular 3M impaction Mesioangular – 43% Vertical – 38% Distoangular – 6% Horizontal – 3%

50. Surgical Anatomy Location: lower 3 rd molar is situated at the distal end of the body of the mandible where it meets a relatively thin ramus. Embedded b/w thick buccal alveolar bone buttressed by external oblique ridge & the narrow inner cortical plate. Ramus offset by 20 ° Retro molar triangle- depressed roughened area post. To 3 rd molar

51. Muscles : Vestibule is formed by the attachment of buccinator buccally and mylohyoid lingually . Along the anterior border of the ramus - tendinous insertion of temporalis excessive stripping of these muscle will cause hematoma, pain and trismus . Lingual pouch – perforation of roots along the lingual cortical plate. - May cause # of lingual cortical plate -Displacement of fractured root fragments below the mylohyoid

52. Arteries Facial artery & facial vein run in close approximation with lower 2 nd molar near the anterior border of masseter . Mandibular vessels in retro molar triangle which supply temporalis tendon. Hemorrhage can occur during surgical removal of impacted tooth if distal incision is not taken laterally towards cheek.

53. Inferior Alveolar Nerve  Lies just below the roots of mandibular molars but slightly buccally placed in inferior dental canal. In case of deep seated impaction special care should be taken to protect this neurovascular bundle during bone drilling & tooth sectioning. Calcification of inferior alveolar canal is completed before the roots of 3 rd molar are formed. Thus growing roots may impinge upon the canal or get deflected. So blind elevation is not advisable.

54. On average( Based on studies of pogrel 1995, holzle 2001, behnia 2000 ) Horizontal distance : 0.6mm medial to mandible Vertical Distance : 2.3 mm below alveolar crest Lingual Nerve

55. Lingual nerve was observed at or above the crest of the lingual plate in about 17% of cases. Distances ranging from 2mm above the crest to 1 mm below the crest. The direct contact of lingual nerve with lingual plate in retromolar triangle was noted in about 50-62 % of cases. With horizontal distances ranging from 0 mm to 7mm Lingual Nerve

56. The retromolar fossa is a triangular area posterior to the third mandibular tooth ( mcminn , 1992). An opening called the retromolar foramen ( rmf ) is known to be present in this area ( ossenberg , 1987).

57. Some researchers suggest that the contents of this canal originate from the mandibular neurovascular bundle before it enters the mandibular canal, While others suggest that these elements arise from the neurovascular bundle in the mandibular canal and lie in the buccal region.

58. Possible hemorrhage of the vascular contents of the neurovascular bundle in this canal or nerve injury during surgical extraction of the impacted mandibular third molars or during sagittal split ramus osteotomies, could adversely effect outcome. Retromolar foramen in the retromolar triangle of the left side ( black arrow ). Bilecenoglu and Tuncer . Clinical and Anatomical Study of Retromolar Foramen and Canal. J Oral Maxillofac Surg 2006.

59. Maxillary third Molar

60. Surgical anatomy

61. Appropriate Timing for Removal of Impacted Teeth The most suitable time to do so is when the patient is young, thus avoiding the aforementioned complications and undesirable situations that could get worse with time. It is easier to remove bone from these patients compared to older patients, whose bone is usually dense and hard. Younger patients generally deal with the overall surgical procedure and stress well, and present fewer complications and faster postsurgical wound healing compared with older patients

62. Assessment of mandibular third molar impaction

63. Winter’s WAR lines

64. White line of winter is drawn along the occlusal surfaces of the erupted mandibular molars and extended posteriorly over the third molar region, the axial inclination of the impacted tooth is immediately apparent. The relationship of the occlusal surface of the impacted tooth to those of the erupted molars may also be estimated by the use of white line and this provide an indication of the depth at which the tooth lying in the mandible.

65. Amber line – is drawn from the surface of the bone lying distally to the third molar to the crest of the interdental septum between the first and second molar. When drawing these line it is essential to differentiate between the external oblique ridge and cast by the bone lying distal to the tooth. The amber line indicate the margin of alveolar bone enclosing the tooth.

66. Red line – is used to measure the depth at which the impacted tooth lies within the mandible. It is perpendicular drop from the ‘amber line’ to an imaginary ‘point of application’ for an elevator. The length of red line increases by 1 mm, the extraction become 3 times more difficult. With the solitary exception of distoangular impaction, the amelocemental junction on the mesial surface of the impacted tooth is used for this purpose. As a general rule any tooth with a red line 5 mm or more in length is better removed under an endotracheal anesthetic.

67. Winter classification (1926) According to the position of the impacted 3rd molar to the long axis of the second molar. Vertical Mesioangular Horizontal Distoangular Buccoangular Linguoangular Inverted

68. The angle between the occlusal plane or a line parallel to the latter and the longitudinal axis of the molar. Molars with a negative angle (<0) were considered to be inverted, Molars with an angle between 0 and 30 were considered to be horizontal, Molars with an angle between 31 and 60 were considered to be mesioangular , Molars with an angle between 61 and 90 were considered to be vertical, Molars with an angle >90 were considered to be distoangular

69. Pell and Gregory’s classification (1933) 1. Availability of space between 2 nd molar and ramus (horizontal plane)

70. 2. Relative depth of 3 rd molar (vertical plane)

71. 3. Long axis of impacted tooth in relation to the long axis of the 2 nd molar. (Winter classification)

72. ADA code on procedures & nomenclatures Describes the amount of soft and hard tissue over the coronal surface of an impacted tooth Soft tissue impactions Complete bony impactions Partial bony impactions Combined ADA & AAOMS classification of procedural terminology 07220:- overlying soft tissue 07230:- partially bony impacted 07240:- completely bony 07241:- completely bony, with unusual surgical complications

73. WHARFE’s assessment RADIOGRAPHIC CHARECTERISTICS CATEGORY SCORE WINTERS CLASSIFICATION Horizontal Distoangular Mesioangular Vertical 2 2 1 HEIGHT OF THE MANDIBLE 1-30mm 31-34mm 35-39mm 1 2

74. ANGULATION OF THE THIRD MOLAR 1˚- 50˚ 60˚- 69˚ 70˚- 79˚ 80˚- 89˚ 90˚+ 1 2 3 4 ROOT SHAPE Complex Favorable curvature Unfavorable curvature 1 2 3

75. FOLLICLE Normal possibly enlarged enlarged impaction relieved -1 -2 -3 PATH OF EXIT Space available Distal cusps covered Mesial cusps covered Both covered 1 2 3 TOTAL 33

76. Difficulty Index for removal of impacted mand third molars - Pedersen 1988 CLASSIFICATION DIFFICULTY INDEX VALUE ANGULATION Mesioangular 1 Horizontal / transverse 2 Vertical 3 Distoangular 4 DEPTH Level A 1 Level B 2 Level C 3 RAMUS RELATIONSHIP / SPACE AVAILABLE Class I 1 Class II 2 Class III 3

77. Difficulty index Very difficult : 7 to 10 Moderately difficult : 5 to 7 Minimally difficult : 3 to 4

78. NEW INDEX SCORE

79. A Comprehensive Proforma for Evaluation of Mandibular Third Molar Impactions Suvy Manuel • L. K. Surej Kumar • Mathew P. Varghese J. Maxillofac . Oral Surg .   DOI 10.1007/s12663-013-0543-2 RELATIONSHIP TO THE INFERIOR ALVEOLAR CANAL (Howe & Poynton -1960 , Rood & Shehab 1990 )   Related but not involving the canal Separated   Adjacent SUPERIMPOSED Related to changes in the canal Darkening of the root Dark & bifid root Narrowing of the root Deflected root Related with changes in the canal Interruption of lines Converging canal Diverted canals  

80. Modified Parant Scale (1997) Easy I - extraction requiring forceps only Easy II - extraction requiring osteotomy only Hard III - extractions requiring osteotomy and coronal section Difficult IV - complex extractions (requiring root resection) A Comprehensive Proforma for Evaluation of Mandibular Third Molar Impactions Suvy Manuel • L. K. Surej Kumar • Mathew P. Varghese J. Maxillofac . Oral Surg.  DOI 10.1007/s12663-013-0543-2

81. Assessment of Maxillary third molar

82. Relationship of maxillary 3 rd molar to sinus Classification

83. Based on depth

84. management

85. PRE-OP MANAGEMENT Thorough review of medical history. Good quality diagnostic x-rays CBCT IF INDICATED

86. Role OF CBCT IN DIAGNOSIS CBCT is required in the preoperative assessment of IMTM when darkening of the roots and interruption of the white line are observed on panoramic images.

87. Review all risks of procedures. Review all post surgical home care instructions. Review surgical procedure utilizing teaching aids. Discuss and evaluate need for sedation . Give patient prescriptions for analgesics and antibiotics

88. Antibiotic prophylaxis in third molar surgery: A randomized double-blind placebo-controlled clinical trial using split-mouth technique. Int. J. Oral Maxillofac . Surg . 2010; 39: 107–114 Effectiveness of Antibiotic Prophylaxis in Third Molar Surgery: A Meta-Analysis of Randomized Controlled Clinical Trials Yan-Fang Ren, DDS, PhD, MPH* and Hans S. Malmstrom , DDS† J Oral Maxillofac Surg.  2007 Oct;65(10):1909-21. Systemic antibiotics given before the surgery were effective in reducing the frequencies of AO and wound infection after third molar surgery. Authors recommend that antibiotic prophylaxis should not be administered routinely when third molars are removed in non immune-compromised patients.

89. Swelling and pain following third molar surgery are the most common findings in our study. Neither correlates with the postoperative antibiotic regime Postoperative antibiotics for 3 days are required in distoangular , horizontal impactions, in difficult impaction (covered by bone), and in cases where the duration of surgery exceeds 30 min to reduce the incidence of alveolar osteitis Decision for postoperative antibiotic regime should be made according to tooth position, the bone surrounding the tooth, the presence or absence of pathology, and the estimated duration of surgery. Antibiotics in third molar extraction; are they really necessary: A non-inferiority randomized controlled trial Natl J Maxillofac Surg . 2014 Jul-Dec; 5(2): 166–171.

90. Preemptive analgesia in third molar impaction surgery Rakesh Shah, Amit Mahajan, Navin Shah, Ashish P. Dadhania National Journal of Maxillofacial Surgery | Vol 3 | Issue 2 | Jul-Dec 2012 Use of diclofenac sodium orally in 50 mg dose one Hour preoperatively as preemptive analgesic agent Is economical, effective, easy and safe method of postoperative pain control in mandibular third molar impaction surgery cases

91. Surgical management of impacted tooth Anaesthesia Incision & elevation of mucoperiosteal flap Removal of overlying bone Delivery of sectioned tooth Smoothening & debridement of socket. Hemostasis Wound closure Post-op follow up

92. INCISION & MUCOPERIOSTEAL FLAP Incision – 3 parts

93. Factors Governing Planning of Incision John tomes (1849) – first to describe surgical access

94. BUCCAL VS LINGUAL APPROACH Criteria Access Operating time Technique Bone removal Postoperative pain Postoperative edema Dry socket

95. SOME COMMoN INCISIONS AND FLAPS used in third molar surgery Ward’s incision and Modified Ward’s incision Comma shaped incision . S -shaped incision Szmyd and modified Szmyd incision Envelope flap Triangular Flap Berwick’s tongue shaped flap.

96. Incision-flap design Ward’s incision Modified ward’s incision

97. COMMA SHAPED INCISION

98. ENVELOPE FLAP

99. SZMYD INCISION(1971)

100. TRIANGULAR FLAP

101. Palatal diagonal flap - Dr . Lee Darichuk (2005) G ives excellent unrestricted access to the maxillary tuberosity region. The Laster and the Minnesota cheek retractors both provide good access to the tuberosity region and prevents displacement of tooth

102. OUTLINE OF INCISION OF THE VESTIBULAR TONGUE-SHAPED FLAP DESCRIBED BY BERWICK

103. Pedicle flap

104. Lingually based triangular flap

105. Lingually based triangular flap

106. INCISIONS AND FLAP DESIGNS Review of flap design influence on the health of the periodontium after mandibular third molar surgery. Oral Surg Oral Med Oral Pathol Oral Radiol Endod 2007;104:18-23 Flap design does not have a lasting effect on the periodontal condition post extraction.

107. BONE REMOVAL Aim To expose the crown by removing the bone overlying it. To remove the bone obstructing the pathway for removal of the impacted tooth. Types By consecutive sweeping action of bur(in layers). By chisel or osteotomy cut(in sections). How much bone has to be removed?

108. Chisel Vs Bur CRITERIA CHISEL & MALLET BUR TECHNIQUE Difficult Easy PT’S ACCEPTANCE Not tolerated well ↓ L.A Tolerated well ↓ L.A CHANCE OF # OF BONE High Low BONE HEALING Good Delayed

109. CRITERIA CHISEL & MALLET BUR POST-OP EDEMA Less More DRY SOCKET Incidence is less Very high POST-OP INFECTION Less More ADV/DISADV Difficult to remove deeply buried impaction Impaction in edentulous jaws & in elderly pts. -Bone removal is less predictable. -Relatively easy to remove

110. Postage and stamp technique. Bone Removal Techniques

111. MOORE/GILLBE COLLAR TECHNIQUE

112. Lateral Trephination tech( Bowdler Henry) It is the removal of a tooth that has one third or less of root formation and also has a radiographically discernible periodontal ligament Employed to remove any partially formed unerupted third molar that has not breached the hard & soft tissues overlying it. Advantages Bone healing is excellent and here is no loss of alveolar bone around 2 nd molar.

113. Coronectomy (partial tooth removal, partial odontectomy or intentional root retention) Angle of the bur at approximately 45° and lingual retractor protecting the lingual nerve ( arrow ). Shaded area of root on buccal side to be removed secondarily. Pogrel , Lee, and Muff. Coronectomy. J Oral Maxillofac Surg 2004

114. A.Coronectomy of an impacted 3rd molar with nerve involvement. B . One year later shows bone formation as well as root migration.

115. The Buccal Lid Approach for Removal of Impacted Mandibular Molars—When, How and Why ? Open Journal of Stomatology, 2017, 7, 81-90 Fares Kablan et al

116. Lingual Guttering Technique for Removal of Impacted Mandibular Third Molars Tejraj P Kale , 1   Vikram S Pandit , 2   Shankargouda Patil , 3   Vivek Pawar , 4  and  Nisha Shetty 5 J Int Oral Health . 2014 Jul-Aug; 6(4): 9–11

117. Two-stage Method for the Extraction of a Horizontally Impacted Lower Third Molar Yasutaka Kubota, Shoji Oka, Yoshie Yahara and Kanemitsu Shirasuna Oral Science International, November 2008, p.73-77   Copyright © 2008, Japanese Stomatology Society. All Rights Reserved

118. Chisel technique through buccal approach

119. Lingual split bone tech (Sir William Kelsey Fry) Popularized by T. Ward Advantages Quick & clean Reduces the size of blood clot by means of saucerization of socket. Disadvantages Only suitable for young adults therefore elastic bone is required More chances of getting post operating lingual nerve paraesthesia Patients inconvenience.

120. Lingual split-bone technique . A. Outline of the incision, B. Reflection of the flap & creation of an anterior vertical stop, C. Removal of buccal plate to expose the crown. D, Placement of a chisel to section the lingual cortex, E. Elevation of tooth, F. Wound closure

121. Uprighting mesially impacted lower third molars with skeletal anchorage Manuel et al jco,july 2016 An orthodontic mini-implant is inserted interproximally on the buccal side of the alveolar ridge, with the exact location determined by clinical and radiographic assessment of the available space.  With direct anchorage from the mini-implants, there is no risk of anchorage loss or undesired tooth movement. Extraction and associated risks such as nerve damage, TMD, and improper wound healing are avoided.

122. ORTHODONTIC EXTRACTION OF THIRD MOLAR

123. Tooth sectioning – when?

124. DELIVERY OF SECTIONED TOOTH Luxation of the distal segment of the tooth with rotation of the elevator distally.

125. DELIVERY OF SECTIONED TOOTH Luxation of the impacted tooth in the distal direction, after creating a pathway for removal.

126. Advantages of tooth division( Pell and Gregory,1942) Bone removal is eliminated or considerably reduced, resulting in less postoperative pain and swelling. Less chances of damage to the adjacent tooth because no effort is made to force the impacted tooth past the convexity of 2 nd molar, which would tend to elevate it out of the socket. The risk of fracture of the reduced, since most fractures occurs from the forced elevation. The danger of injury to IAN, which frequently follows heavy leverage forcing the apex of the tooth down into the canal, is greatly lessened.

127. Recent advances Use of erbium ( er ): yag laser M.Abu-serriah / A.Ayoub : bjoms 2004; 42: 203-208] Advantages Less stressful Less unpleasant No vibrations & sound Sharp clean cut through the bone & tooth Can used anxious patients Disadvantages Compensate for tactile feedback compare to bur. Trismus is more Time consuming Costly

128. Use of endoscopic approach for ectopic mandibular 3 rd molar (BJOMS 2003; Oct. 41: 340-42) Advantages Less tissue damage Clear magnified visualization of operative field More conservative surgery with precise dissection. Disadvantages Costly Need basic equipments Good eye coordination and training

129. Debridement of wound & closure Thorough debridement of the socket by periapical curette Smoothening of sharp bony margins by Bone file / round burs Thorough irrigation of the socket POVIDONE IODINE solution / saline Initial wound closure is achieved by Just distal to 2 nd molar Posterior relieving incision Inter dental area mesial to 2 nd molar 3-4 sutures are usually sufficient

130. Assessment of the effect of wound closure technique on postoperative sequele and complications after impacted mandibular third molar extraction E. O. Anighoro1 , O. M. Gbotolorun2*, R. A. Adewole2 , G. T. Arotiba2 , O. A. Effiom3 Open Journal of Stomatology, 2013, 3, 527-532 Wound closure methods have little or no effect on the rate of complications after the third molar removal.

131. Post Operative Instructions Pressure pack Ice application Soft diet –1 st two days 1 st dose of analgesic should be taken before the anesthetic effect of LA wears off. Avoid gargling / spitting / smoking / drinking with straw. Warm water saline gargling after 24 hrs + mouth wash regularly thereafter. Suture removal on 7 th pod.

132. Complications(common and during mandibular third molar surgery) Intra operative 1. During incision a. Hemorrhage B. Injury to lingual nerve 2. During bone removal A. Damage to second molar B. Slipping of bur into soft tissue & causing injury C. Extra oral/ mucosal burns D. Fracture of the mandible when using chisel & mallet E. Subcutaneous emphysema

133. 3. During elevation or tooth removal A. Luxation of neighboring tooth/ fractured restoration B. Soft tissue injury due to slipping of elevator C.  Injury to inferior alveolar neurovascular bundle D. Fracture of mandible E. Forcing tooth root into submandibular space or inferior alveolar nerve canal F. Breakage of instruments G. TMJ dislocation

134. Nerve Injuries

135. 0.6-5% of all the third molar surgeries are involved with nerve damages of which 0.2% are irreversible Ian: immediate disturbance - 4-5% (1.3-7.8%) Permanent disturbances - <1% (0-2.2%) Lingual n: immediate - 0.2-22% Permanent - 0-2% Buccal nerve injury-very rare 96% IAN injuries show spontaneous recovery within 9 months, better than lingual nerve which is about 87% Beyond 2yrs recovery is unlikely

136. Less chances of lingual nerve regeneration compare to inferior alveolar nerve – Morphological difference In addition, the presence of a range of functionally Distinct nerve fibre types in this nerve ( Mechanosensitive , thermosensitive , Gustatory, vasomotor and secretomotor ) May make successful regeneration of the axons back to the correct receptor/effector and location less likely

137. Tooth displacement in Lingual pouch

138. Complications of maxillary third molar surgery Fracture of maxillary tuberosity – if the operator anticipates such a fracture, avoiding reflection of the periosteum will preserve the blood supply and will provide the best chance of survival postoperatively. Oroantral fistula Displacement into maxillary sinus If entire tooth is displaced it should be removed as early as possible to prevent infection.

139. According to pogrel (1990) initial attempt should be with a suction at the opening, if it fails irrigate with saline again use suction. If again fails place the patient on antibiotics and nasal decongestants and plan Caldwell Luc approach.

140. Dislodged into infratemporal fossa The tooth should be removed as early as possible to avoid infection. Put an incision and try to retrieve with a haemostat or A llis forceps. If it is not possible wait till fibrosis occurs and tooth become stable. And place the patient under antibiotic coverage.

141. Damage to adjacent 2 nd molar -during bone removal and elevation. Prolapse of buccal fat pad

142. Post-operative Immediate Pain Hemorrhage Swelling Trismus Paraesthesia Late Infection Dry socket Osteomyelitis Secondary hemorrhage Pain in TMJ

143. Dry Socket 20% of extraction of mandibular 3 rd molar 2% of routine extraction Moderate-severe pain develops generally on 3 rd /4 th day.(With no signs of infection) Dull aching pain usually radiates to ear Empty socket Bad odour & taste Etiology - unknown Possibly excessive fibrinolytic activity Subclinical infection

144. Management Gentle irrigation with warm saline followed by superficial suctioning. Pack iodoform gauze socked with medications change every day for 3-6 days. Intra-alveolar medicaments -With eugenol -Topical LA - Antifibrinolytic agents. Analgesics.

145. Controversies General vs. Local anaesthesia Surgical removal of wisdom tooth can be done under local anaesthesia or general anaesthesia. The decision to use either anaesthesia depends on the condition of the wisdom tooth and the judgment of the operating dental surgeon.

146. Indication for general anaesthesia Allergy to local anaesthesia. Medically compromised patients. Uncooperative patients. Patients with need of a comprehensive dental treatment .

147. The use of preoperative corticosteroids to minimize swelling, trismus and pain has gained wide acceptance in the practice of oral and maxillofacial surgery. Steroids act by interfering with capillary vasodilation, leukocyte migration, phagocytosis, cytokine production and prostaglandin inhibition. Use of Steroids

148. Impacted teeth as potential source of infection Prior to administration of radiotherapy:- Teeth at risk of infection which could result in osteoradionecrosis or endocarditis should be removed. Cardiac patients :- Cardiac patients with valvular disease or those who have undergone valve replacement have evidence of molar periodontal defects and inflammatory mediators in their crevicular fluid; should have asymptomatic third molars removed.

149. Asymptomatic impacted tooth “If impacted teeth are left in the alveolar process, it is highly probable that one or more of a number of problems will result”. (Peterson’s Contemporary Oral and Maxillofacial Surgery ) National Institutes of Health Consensus Development Conference: Removal of third molars also supported that “ third molars should be removed in the younger age patient because there is less transitory or permanent morbidity,” and less anaesthetic risk.

150. To retain or to remove

151. Risks and benefits of removal of impacted third molars A critical review of the literature P. Mercier, D. Precious Departments of Oral and Maxillofacial Surgery, St, Mary's Hospital, Montreal, and Dalhousie University, Halifax, Canada P. Mercier, 1). Precious." J . Oral Maxillofac . Surg. 1992; 21:17 27. T he best general approach is to remove, on the basis of clinical judgement, some teeth before the age of 14 and others before the age of 22, when chances of eruption are minimal. The best strategy after this age is periodic examination of a patient who has been fully informed of the relevant risks and benefits. Ultimately, as in every treatment decision, the surgeon must weigh the facts and put the interests of the patient above all else. This is our professional responsibility.

152. Prophylactic Extraction of Third Molars: Evidence-Based DentistrY costa rican journal,2016 There is a lack of reliable evidence to support the prophylactic removal of disease-free itm in adolescents and young adults. As routine procedure, this treatment is unjustifiable. A more suitable strategy is the active and careful monitoring, at regular intervals, of asymptomatic itm , based on clinical experience. Each case of itm should be carefully and individually assessed, estimating the balance between risk, benefit, and cost. The patient’s perspectives and values must be taken in account in the clinical decision-making process.

153. Surgical removal versus retention for the management of asymptomatic disease-free impacted wisdom teeth Cochrane journal,2016 In light of the lack of available evidence, patient values should be considered and clinical expertise used when treatment decisions are made with patients who have asymptomatic disease free impacted wisdom teeth. If the decision is made to retain asymptomatic disease-free impacted wisdom teeth, clinical assessment at regular intervals is advisable to prevent undesirable outcomes.

154. Year  : 2017  |   Volume  : 29  |   Issue  : 1  |   Page  : 20-24 Predicting pathology in impacted mandibular third molars Aveek Mukherji ,  Mohit Pal Singh ,  Prashant Nahar ,  Bhuvaneshwari S Balaji ,  Hemant Mathur ,  Saurabh Goel Department of Oral Medicine and Radiology, Pacific Dental College and Hospital, Debari , Rajasthan, India Asymptomatic patients who decide to retain their third molars should have periodic clinical and radiographic examinations to detect any disease before it becomes symptomatic. 

155. Conclusion All patients with impacted third molars should be evaluated and treatment planned should be based on their individual presentation, and should not be subjected to a ‘‘standardized generic treatment protocol.’’ “ Bone & soft tissues belongs to the patient and only the tooth belong to the surgeon”

156. References Evidenced-Based Decision Making: The Third Molar; Dent Clin N Am 53 (2009) 77–96 . Do pathologies associated with impacted lower third molars justify prophylactic removal? A critical review of the literature Wasiu Lanre Adeyemo , BDS, FMCDS,a Lagos, Nigeria (Oral Surg Oral Med Oral Pathol Oral Radiol Endod 2006;102:448-52) Oral Maxillofacial Surg Clin N Am 19 (2007) Factors influencing the prophylactic removal of asymptomatic impacted lower third molars. N. Almendros-Marque´s, E. Alaejos-Algarra, M. Quinteros-Borgarello, L. Berini- Ayte´s , C. Gay- Escoda : ( Int. J. Oral Maxillofac. Surg. 2008; 37: 29–35) REFERENCES

157. Andreasen , Peterson, Laskin : Textbook and Color Atlas of Tooth Impactions,1997, Munksgaard Peterson, Ellis, Hupp, Tucker : Contemporary Oral and Maxillofacial Surgery ed 2, 1993, Mosby-Year Book. Alling , Helfrick , Alling : Impacted Teeth, 1993, Mosby-Year Book. Daniel M. Laskin : Oral And Maxillofacial Surgery Vol 2 Oral Surgery, 2003, C.V.Mosby Company. Killey And Kay’s Outline O Oral Surgery, Part I, ed 2, 1987, IOP Publishing Company. Neelima Anil Malik: Text Book Of Oral And Maxillofacial Surgery

158. MINOR ORAL SURGERY - GEOFfReY L. HOWe TEXT BOOK OF ORAL AND MAXILLOFACIAL SURGEY- SRINIVASAN TEXTBOOK OF ORAL AND MAXILLOFACIAL SURGEY - KILLEY & KAY

159. Thank you………