DEVELOPMENTAL DISTURBANCES AFFECTING THE STRUCTURE OF TEETH.ppt

QUINTESSENCE-NEWS

1. Hypoplaisa of Deciduous Dentition & Permanent Dentition
Hypoplasia of Deciduous Dentition due to :
Neonatal Hypoplasia
Kernicterus
Allergic reaction
Tetracycline

2. Hypoplasia of permanent dentition due to :
- Defective formation
- Defective Mineralization.
Causes of Hypoplasia :
Local Causes :
Local infection
Trauma

3. General causes :
I. Hereditary & Idiopathic Hypoplasia of enamel and dentine :
Hereditary dentinogenesis imperfcta.
Hereditary & Idiopathic Amelogenesis imperfecta.
Hereditary Enamel Hypoplasia
Hereditary & idiopathic enamel Hypomineralization.

4. II. General Diseases of Genetic or Idiopathic origin :
Epidermolysis bullosa Dystrophica
Cleido Cranial Dysostosis
Osteogenesis Imperfecta
Osteopetrosis

5. III. Prenatal or Congenital Syphilis :
IV. Trophic Disturbances :
Gastro Intestinal disturbances.
Infantile tetany
Vit.A, C, D & Calcium & Phosphorus deficiency
Vit.C. Deficiency
Exanthemata.

6. V. Endemic Fluorosis :
Witkop sub divides :
Hereditary Idiopathic Amelogenesis Imperfecta into five groups -
1. Hypoplasia of Enamel
2. Hypocalcification.
3. Hypomaturation.
4. Pigmented Hypomaturation.
5. Local Hypoplasia of Hereditary origin.

7. DEVELOPMENTAL DISTURBANCES IN STRUCTURE OF TEETH
Disturbances in the structure of enamel -
I. Classification of enamel Hypoplasia -
Hereditary enamel Hypoplasia :
1. Amelogenesis Imperfecta ;
a. Hypoplastic Type : Matrix formation defective.
b. Hypo calcified Type : Matrix mineralization defective.
c. Hypo Maturation Type : Maturation of enamel crystalite - defective.
2. Environmental Hypoplasia :
1. Hypoplasia due to nutritional deficiencies and exanthamatours fevers.
2. Enamel Hypoplasia due to congenital syphilis
3. Enamel Hypoplasia due to Hypocalcification.
4. Enamel Hypoplasia due to Birth Injuries.
5. Enamel Hypoplasia due to Infection and Trauma - Turner's Hypoplasia.
6. Enamel Hypoplaisa due to fluoride - Mottling of teeth.
7. Enamel Hypoplasia due to Idiopathic factors.

8. II. Classification of Dentinal Hypoplasia :
1. Dentinogenesis Imperfecta (Dentinal Hypoplasia).
2. Dentine Dysplasia (Root less teeth)
3. Regional odonto Dysplasia (Ghost teeth)
4. Dentine Hypo calcification.

9. Amelogenesis Imperfecta :-
(Hereditary enamel Dysplasia or Hereditary brown enamel or Hereditary brown Opalescent teeth)
- A group of Hereditary defects of enamel unassociated with any other defects.
- An entirely Ectodermal Disturbances (As the mesodermal derivatives are normal).
Classification of Amelogenesis Imperfecta -
1. Hypoplastic (Defective formation of Matrix)
a. Pitied
b. Local Autosomal Dominant.
‑
c. Smooth
d. Rough
e. Rough - Autosomal Recessive
f. Smooth - X - Linked dominant

10. 2. Hypocalcified (Defective Mineralization of the formed matrix)
a. Autosomal Dominant.
b. Autosomal Recessive
3. Hypomaturation (Defective maturation of enamel Crystallites)
a. Hypomaturation - Hypoplastic with Taurodontism Autosomal Dominant.
b. X - Linked Recessive
c. Pigmented - Autosomal Recessive
d. Snow capped teeth.
Clinical :
1. Hypoplastic Type - Enamel not formed to full normal thickness on newly erupted
developing teeth.
2. Hypocalcified Type - Enamel very soft which can be removed by any instrument.
3. Hypomaturation Type - Enamel can be pierced by an explorer and/or easily chipped
off dentine normal
- Clinical appearance varies formation to unsightly
- Both dentitions affected
- Clinical appearance may vary from males to females
- Color of enamel varies from yellow to dark brown
- Mostly only enamel is involved
- In some cases enamel may be absent or may have a chalky white texture or a cheesy
consistency or hard.
- Enamel surface may be smooth or wrinkled surface with vertical grooves.
- It may be chipped off or show depressions exposing dentine
- Contact points open
-Occlusal and incisal area show severe abrasion
Radiologic :
- Shape of the tooth depends upon the amount of enamel present and amount of occlusal
and incisal wear.
- Enamel absent or thin only on tips of cusps and proximal surface.
- May show same density as dentine - poor calcification.
Histopathology :
1. Defective matrix formation to absence.
2. Defective matrix and mineralisation
Alterations in rod and rod sheath
Treatment : Cosmetic Improvement

11. 2. Environmental Enamel Hypoplasia :
Definition : -
Enamel hypoplasia - Incomplete or Defective formation of the organic enamel matrix.
Environmental type - Either dentition or a single tooth. Both enamel and dentine involved to certain extent.
Etiology :
1. Nutritional Deficiencies - Vit.A, C and D.
2. Exanthamotous diseases - measles, chicken pox, scarlet fever.
3. Congenital Syphilis.
4. Hypocalcemia.
5. Birth injury, prematurity, Rh-Haemolytic disease.
6. Local infection or trauma.
7. Ingestion of chemicals - fluorides.
8. Idiopathic.

12. MILD :
- A few small grooves pits or fissures on the enamel surface.
SEVERE :
- Rows of deep pits across the surface of the tooth. Single or several rows of
pits indicating series of injuries.
MOST SEVERE :
- A considerable portion of enamel absent due to prolonged disturbance the function of
Ameloblasts.
- Hypoplasia results only if the injury occurs during the formative stages of tooth
development.
CHRONOLOGIC :
- Knowing the chronologic development of tooth tissue and the location of defect it is
possible to determines the approximate age at which the injury has occurred.
1. Hypoplasia due to Nutritional Deficiency and Exanthamatous fever :
Etiology :
- Nutritional deficiency like Vit.D (Rickets), A and C
- Exanthamotous fevers like, Measles, Scarlet Fever, Chicken Pox, etc.,
- Ameloblasts are the most sensitive cells in the body in their metabolic function.
- Pitting and unsightly appearance of the teeth.
- Mostly the teeth affected are the ones which are formed during or after the first year after
birth.
- Central incisors, Lateral incisors, Cuspids and first molars.
- Pre molars, Second and Third molars rarely affected as their formation begins around 3
years or later.
- Caries after initiation may spread fast in Hypoplastic teeth.

13. 2. Enamel Hypoplasia due to congenital syphilis :
- Not of pitting variety.
- Presents a and pathogonomonic appearance.
- Involves permanent maxillary. and Mandibular. incisors and first molars
- Anterior teeth - Barrel or Screw driver shaped teeth.
- Molar - Mulberry molars or moon's molars / Fournier’s molars.
- Upper central incisors - is screw driver shaped - the mesial and distal surfaces of crown
converging towards the incisal edge.
- The incisal edge is usually notched - 'Hutchinson's teeth - Mandibular Incisors similarly
involved
- Maxillary laterals may be normal.
- Tapering and notching of central incisors. is due to absence of central tubercle or
calcification center.
- First molars - Occlusal third and occlusal surface appear to be arranged in an
Agglomerate mass of Globules - no cuspal details. Occlusal third smaller than cervical
third.
Diagnosis of congenital. syphilis should never be done on the basis of teeth alone.

14. Hutchinson's Triad :
- Hypoplasia of incisors and molars.
- Interstitial Keratosis and
- Eighth nerve deafness.

15. 3. Enamel Hypoplasia due to Hypocalcemia :
ETIOOGY :
- Cal. Deficiency due to Vit.D and Parathormone -
tetany - 6-8 mg/100 ml serum level.
- Pitting Hypoplasia of enamel.

16. 4. Hypoplasia due to birth injuries :
- Neonatal line and ring - Deciduous and first molar.
- Traumatic birth, premature birth, Rh-Haemolytic Anemia
- Gastro intestinal disturbances.
- Enamel and Dentine Hypoplasia.

17. 5. Enamel Hypoplasia due to infection and trauma :
- A single tooth is involved.
- Permanent max. incisors or mandibular. premolars
- Mild brownish discoloration of enamel to - severe pitting and irregularity of crown
surface.
- Turner's teeth or Turner's Hypoplasia
- Periapical infection of a deciduous tooth affecting permanent tooth germ.
- Severity depends on severity of infection and stages of development of the tooth.
- Concussion of deciduous tooth - injury to the permanent tooth germ. -
- Yellowish or brownish stain or pigmentation of enamel on labial surface or pitting defect
or deformity.

18. 6. Enamel Hypoplasia due to Fluoride - Mottled Enamel :
Etiology :
- More than 1.0 part/million of fluoride in dry waters when the teeth are developing.
- Due to disturbance of Ameloblasts during formative stage of tooth development.
- Histology evidence of cell damage - defective matrix
- Formation - Interference with calcification process
- Individual variations in degree of Hypoplasia seen to different levels of fluoride.
Clinical : Wide range of severity.
1. Questionable : - Occasional white flecks or spotting of enamel.
2. Mild : - White opaque areas involving more of the tooth surface.
3. Moderate and severe : - Pitting and brown staining, wear and fracture of enamel
Corroded : - Corroded appearance of the teeth.
Treatment : Bleaching periodically.

19. II. Dentinal Hypoplasia :
1. Dentinogenosis imperfecta :
(Hereditary Opalescent Dentine) or (Odonto
Genesis Imperfecta)
- Sometimes associated with Osteogenesis
imperfecta.
Shield's Classification of dentine genesis
imperfecta -
Type I - Occur in families with Osteogenesis
imperfecta.
- Autosomal dominant with variable
expressivity
- More severe in deciduous teeth.
Type II - Never Occurs in association with
Osteogenesis imperfecta.
- Autosomal dominant
- Common - brown Opalescent
dentine
Type III - Brandy wine Type : Same as I and
II but with multiple pulp exposures in
deciduous teeth.
- Autosomal dominant.
Clinical :
- Color of teeth range from gray to brownish
violet or yellowish brown with characteristic
translucent or opalescent hue.
- Enamel is lost due to fracturing away due to
abnormal dentine on the occlusal and incisal
absent.
- Underlying dentine undergoes rapid attrition
and occlusal surfaces of dec. and per.
molars flattened.
- Tendency for root fractures - more
- Not susceptible to caries.
Radiologic :
- Type I and II - partial or total obliteration of
the pulp chambers and root canals by
continued formation of dentine.
- Deciduous. and permanent teeth.
- Root short and blunt
- Other structures normal.
- Type III - "Shell - Teeth" - Enamel normal
dentine very thin and pulp chambers large
and
roots short.
Histopathology : Enamel normal

‑
Dentine shows - Irregular tubules with large
areas of uncalcified matrix.
Type I- Tubules larger in diameter and less in
number or and II absent in some areas.
- Tubules may show cellular inclusion -
odontoblasts
Pulp chambers obliterated by dentine
formation.
Odontoblasts d is not well
organized matrix.
‑
Not known.
Chemical and Physical Features -
Less content
more (more than 60%
than normal)
Density and hardness low (equal to
cementum) leads to rapid attrition.
Treatment : Crowns for prevention attrition -
fillings useless.

20. 2. Dentine Dysplasia : (Root less
teeth)
- Rare disturbance of dentine formation
with abnormal pulp morphology.
- Normal enamel.
Witkop :
Etiology - Hereditary - Autosomal
Dominant.
Clinical
- Characteristically exhibit
mobility
- Teeth exfoliated prematurely or
after minor trauma
- Teeth with short roots.
Type II Coronal -
- Appearance of Deciduous teeth like
dentinogenesis imperfecta
- Appearance of Permanent. teeth
normal.
Radiologic :
Type I - Radicular -
- Roots, short, blunt, conical malformed
- In dec. teeth - Pulp chambers and
root canals obliterated
- In perm. teeth - pulp obliteration, per
Eruption, a crescent like pulp still may
be seen.
- Several Periapical lesions in relation
to intact teeth.
Type II
Histopathology : Atypical structure of
dentine.
Type I Radicular -
- A portion of the coronal dentine is
normal tubular.
- Rest of the whole dentine is - calcified
tubular.
- Osteo dentine
- Fused pentacles.
- New dentine former appears like
"Larva Flowing Around Boulders"
As the tubule formation is blocked or
pattern of 'Cascades of Dentine" (an
attempt at formation of root structure
dentine histologically normal but
disoriented.
Type II Coronal :
I. Deciduous teeth - Amorphous and
atubular dentine in the radicular
portion.
- Crown dentine normal.
Permanent teeth show pulp
stones and denticles.

21. 3. Regional Odonto Dysplasia :
(Odonto Dysplasia or Odontogenic Dysplasia or Odontogenesis Imperfecta)
"Ghost Teeth".
One or several teeth
More in
- Rare in
Deciduous
Etiology :
- Somatic mutation
- Latent virus in odontogenesis
- Vascular
- Vascular defects.
Clinical : Delay or total failure of eruption.
- Irregular in shape defective mineralization.
Radiologic : Marked reduction in radio-density - ghost appearance
- Both enamel and dentine thin - or enamel - not evident.
- Pulp chamber exceedingly large.
Histopathology:
Treatment : Extraction.

22. 4. Dentine Hypocalcification :
- Failure of fusion of many Globular areas of calcification.
- many inter globular areas unmineralized.
- Softer dentine.
- Etiology similar to environmental enamel Hypocalcification - and
hypoplasia - i.e. factors with calcification.
Treatment : Caution in operative procedures.

23. DEVELOPMENT DISTURBANCE IN STRUCTURE OF TEETH
I. Enamel Hypoplasia
1. Amelogenesis imperfecta
a. Hypoplastic type
b. Hypocalcified type
c. Hypomaturation type
2. Environmental Hypoplasia
a. Hypoplasia due to nutritional deficiency and exanthematous fevers.
b. Enamel Hypoplasia due to congenital syphilis
c. Enamel hypoplasia due to Hypocalcification
d. Enamel Hypoplasia due to birth injuries
e. Enamel Hypoplasia due to infection & Trauma
f. Enamel Hypoplasia due to Fluoride.
g. Enamel Hypoplasia due to Idiopathic factors.

24. II. Dentinal Hypoplasia
1. Dentinogenesis imperfecta (Dentinal hypoplasia)
2. Dentine Dysplasia (Root less teeth)
3. Regional Odonto dysplasia (Ghost teeth)
4.Dentine Hypocalcification.

25. WHITKOP'S CLASSIFICATION OF AMELOGENESIS IMPERFECTA
:
1. HYPOPLASIA OF ENAMEL.
2. HYPOCALCIFICATION.
3. HYPOMATURATION.
4. PIGMENTED HYPOMATURATION.
5. LOCAL HYPOPLASIA OF HEREDITARY ORIGIN.

26. CAUSES OF ENAMEL & DENTIN HYPOPLASIA.
___________________|__________________
| |
GENERAL. LOCAL.

HEREDITARY :
LOCAL INFECTION.
Dentinogenesis Imperfecta. - TIOTXxÅÃN£b
Idiopathic Amelogenesis Imperfecta.
Enamel Hypoplasia.
Idiopathic Enamel Hypomineralization.

27. -DISEASES OF GENETIC OR IDIOPATHIC ORIGIN :
Epidermolysis Bullosa Dystrophica.
Cleidocranial Dysostosis.
Osteogenesis Imperfecta.
Osteopetrosis.

28. PRENATAL OR CONGENITAL SYPHILIS :
- TROPHIC DISTURBANCES :
Gastrointestinal disturbances.
Infantile tetany.
Vit A,C & D, Calcium and Phosphorus deficiency.
Exanthemata.

29. ENDEMIC FLUOROSIS :
2. ENAMEL HYPOPLASIA DUE TO CONGENITAL SYPHILIS.
Not of pitting variety. Involves anterior & posterior teeth.
HUTCHINSONS TEETH :
Central Incisors : Screw driver shaped, notched incisal edge. Tapering - due to absence of
central tubercle or calcification centre.
First Molars : Occlusal surface appears to be arranged in an agglomerate mass of globules.
No cusps - Occlusal third smaller than cervical third. Mulberry molars, Moons molars, or
Fourniers molars.

30. HUTCHINSONS TRIAD.
Hypoplasia of incisors & molars.
Interstitial Keratitis.
Eighth Nerve deafness

31. CLASSIFICATION OF AMELOGENESIS IMPERFECTA :
|
_________________|____________________
| | |
HYPOPLASTIC HYPOCALCIFIED HYPOMATURATION
(Matrix formation - (Matrix mineraliztion - (Maturation of
Defective) Defective) Enamel crystallites
Defective)
Pitted -Autosomal - Hypomaturation -
Local -Autosomal dominant & hypoplastic with
Smooth - dominant. -Autosomal
Taurodontism -Autosomal
Rough - recessive. dominant
-Linked recessive.
Rough - Autosomal -Pigmented - Autosomal
recessive.
   recessive
Smooth - Linked dominant. -
Snow Capped Teeth.