1. Developmental anomalies of the teeth, specific and non – specific disorders of hard dental tisuess
6 DM

2. Developmental anomalies
tooth development is strict under genetic control
disturbances in tooth development result from gene mutation
tooth development may be disturbed at different stages of morphogenesis
definitive result depends on the timing and the type of insult

3. Developmental anomalies
Disturbances in tooth development:
numerical variations (missing or supernumerary teeth)
variations in size of teeth
variations of shape of teeth
disturbances in eruption

4. Developmental anomalies
Numerical variations
1.Hypodontia
number of teeth is decrease
the most commonly missing teeth are:
the third molars, second premolars, maxillary lateral incisors
- oligodontia, anodontia, agenesis

5. Developmental anomalies
Numerical variations
1.Hypodontia in deciduous dentiotion:
- prevalence 0.1 – 0.7%
central incisors
oligondontia and anodontia is rare, may be found in connection with ectodermal dysplasia

6. Developmental anomalies
Ectodermal dysplasia:
describes a group of developmental, often inherit, disorders involving the ectodermally structures(hair,teeth, nails, skin and sweat glands)
presentation:multiple missing teeth, fine, sparse hair, dry skin, maxillary hypoplasia, eversion of the lips, pigmentation around the mounth and eyes. The teeth are conical, small, often with a large diastema.

7. Developmental anomalies
Numerical variations
1.Hypodontia in permanent dentiotion:
prevalence 6 – 10%
usually affects 2 or more teeth in 50% of the cases
often occures symmetrical hypodontia
particular relation with the microdontia

8. Developmental anomalies
Solitary median maxillary central incisor syndrome
is very rare
midline symetrical maxillary central incisor
can be associated with cleft palate, choanal stenosis, umbilical hernia, hypoplasia of sella turcica, pituitary dysfunction, growth hormone deficiency

10. Developmental anomalies
Numerical variations
2. Hyperodontia
number of the teeth is increse
is quite rare as hypodontia
Frequency: primary teeth 0,3 - 0,8%
permanent teeth 1,0 – 3,5%

11. Developmental anomalies
Numerical variations
2. Hyperodontia
- shape is conical or normal
supernumerary teeth can erupt or cause anomalous eruption of neighbouring teeth
most frequent is mesiodens
part of syndrom cleidocranial dysplasia

12. Developmental anomalies
Cleidocranial dysplasia:
short stature
aplasia or hypoplasia of clavicles
delayed ossification
delayed eruption of teeth
dentigerous cyst formation

13. Developmental anomalies
Dentes praelactales
frontal region in a newborns
no roots
Th: extraction

15. Developmental anomalies
Variations in tooth size:
Macrodontia
teeth are larger than normal
true macrodontia involving the whole dentition
2. Microdontia
one or more teeth are smaller than normal
most affect the maxillary third molars

16. General microdontia: is a rare conditionoccuring in connection with congenital
Local microdontia: involving single teeth, associated with hypodontia
3. Rhizomicry
-lenght of the root is shorter than the height of the crown
connected with osteoporosis
predominantly affecting maxillary incisors and premolars

17. Developmental anomalies
Variations on tooth shape
Dens invaginatus
malformation due to an invagination of enamel epitelium resulting in a chanel or lumen surrounded by hard tissues within the tooth. The anomaly occurs most frequently in the palatal surface of max. lateral incisor.
2. Conical peg-shaped tooth

18. Developmental anomalies
Variations on tooth shape
3. Taurodontism
elongated root- stem with the furcation more apical than normally
4. Double formation of teeth
a) concrescence- two normal appearing crowns are present and the fusion involves only the cementum

19. Developmental anomalies
Variations on tooth shape
b) Fusion – union in dentin and/or enamel between two or more normal teeth
c) Gemination – incomplete division of a tooth germ or a union between normal and a supernumerary tooth
5. Dnes evaginatus
- is an extra cusp, usually in the central groove or ridge of a posterior teeth and in the cingulum of the central or lateral incisor

20. Developmental anomalies
6. Dens in dente
is a condition resulting from invagination of the inner enamel epithelium producing the appearance of a tooth within a tooth
7. Dilaceration
- an abnormal bend of the rooth during its development and is thought to result from a traumatic episode

23. Developmental anomalies
Variations in tooth eruption
tooth retention
tooth semiretention
anomalous position after eruption

24. Non – specific disorders of hard dental tisuess
Hypoplasia
Hypomineralization
Hypoplasia:
Ethiology:- metabolic disorders, fever, endocrinic disease,trauma, inflammation
Cl. picture: anomalous shape of dental crown, grooves and fissures, color-dark brown, yellowbrown.

25. Non – specific disorders of hard dental tisuess
Hypomineralization:
Ethiology:- metabolic disorders, fever, endocrinic disease,trauma, inflammation
Cl. picture: normal shape of dental crown, in hard dental tisuess are quality changes. Color- white or brown smudges, localization on labial surfaces of incisors

26. Specific disorders of hard dental tisuess
Dysplasia of hard dental tisuess
1.DENTIN DYSPLASIA
Ethiology: ingestion of chemicals, prematurity birthweight, severe malnutrition, bilirubinemia
Typ I: radicular dentin dysplasia or rootless tooth
Typ II: anomalous dysplasia of dentin with frequent discoloration of primary teeth, permanent teeth often appear normal clinically but have thistle-tube formed pulp chamber. Pulp stones may occure.

27. Specific disorders of hard dental tisuess
2. Fluoride induced defect

28. Specific disorders of hard dental tisuess
3. Tetracycline defects
- TTC has a strong affinity to mineralized tisuess, primary to dentin and bones
dentin defects are persistent
discolored horizontal bands may appear gray, bluish
discolored enamel has some translucency left
this ATB shoud not be prescribed to children below the age of 8, pregnant women, lactating mothers

29. Specific disorders of hard dental tisuess
4. Molar – incisor hypomineralization
demarcated opacities in the perm. first molars, perm. incisors are often also involved
may affect one or all molars and one or more incisors
creamy white spot to yelowish brown discoloration
defect are porous

30. Specific disorders of hard dental tisuess
Subj. symptoms:
shooting pain during brushing teeth or breathing cold air
Ethiology:
- unknown, but suggestion are: medical problem related to birth, respiratory diseases during first 3 years of life

32. Specific disorders of hard dental tisuess
Amelogenesis imperfecta
Definition:AI represents a roup of condition, genomic in origin, which affect the structure and clinical appearance of the enamel of all or nearly all teeth in a more or less equal manner, and which may be associated with morphologic or biochemical changes elsewhere in the body.

33. Specific disorders of hard dental tisuess
- autosomal dominant, autosomal recessive
incidence 1 in
4 major categories, 14 subtypes
General manifestation:
normal intelligence, good general health
Craniofacial/dental manifestation:
enamel defect that affects both dentitions, appearance is yellow- brown to orange depending on subtyp

34. Specific disorders of hard dental tisuess
Typ I:- hypoplastic (occuring in the histodifferation stage of tooth development, insufficient quantity of enamel is formed)
TypII:- hypomaturation (defect of in enamel matrix apposition)
Typ III:- hypocalcified (enamel is normal, but qualitatively the matrix is poor calcified with a resultant fracturing of the enamel surface. Hypocalcified enamel is soft and fragile, especially at the incisal region, and is easily fractured, exposing dentin.

35. Specific disorders of hard dental tisuess
Typ IV:- hypomaturation, hypoplastic with taurodontism (the enamel appears mottled with a yellow-brown color and is pittedon the facial surfaces. Molar teeth demonstrate taurodontism.

37. Specific disorders of hard dental tisuess
Dentinogenesis imperfecta
Defect of predentin matrix that result amorphic, disorganized, and atubular circumpulpal dentin.
incidence 1 in 8000
3 basic types
Shields type 1
Shields type 2
Shields type 3

38. Specific disorders of hard dental tisuess
Shields type 1
occurs with AI
inherit defect in collagen formation
osteoporotic brittle bones
bowing of the lips
blue sclera
bitemporal bossing
obliteration of pulp chamber,periapical radiolucencies, bulbous crowns, root fractures

39. Specific disorders of hard dental tisuess
Shields type 2
hereditary opalescent dentin
autosomal dominant
affect primary and permanent dentition
Shields type 3
is rare, bell-shaped crown,
it has occured exclusively in a triracial isolated group in Maryland

40. Specific disorders of hard dental tisuess

41. Specific disorders of hard dental tisuess