Developmental Anomalies Flashcards
Causes of Developmental Anomalies
- Genetic
Inherited or gene mutation. - Environmental causes
Infection, trauma, radiation.
hormonal disturbances.
nutritional deficiencies.
hypoxia
miscellaneous
Anomalies in tooth size
Microdontia
Macrodontia
clinically: single macrodont is difficult to be identified from gemination or fusion
Developmental Anomalies in
Teeth Number
Increased number
Supernumerary teeth
Predeciduous dent
Post permanent dent
Decreased number
Hypodontia
Oligodontia
Anodontia ( Ectodermal Dysplasia, Radiation to head)
Supernumerary teeth- Arise from extra-teeth buds. Rare in deciduous teeth. May resemble the tooth anatomically or not
Mesiodense: between 1,1. Small, conical inverted, impacted, short root
Paramolars: located
around the premolarmolars
Distomolar: Distal to # 8, small, rudimentary
Multiple Supernumerary Teeth Are manifested in
**1. Gardner’s Syndrome: **multiple supernumerary and impacted teeth, multiple polyps of large intestine,multiple osteomas , sebaceous cysts.
2. Gorlin-Goltz Syndrome: (basal cell nevousbifid rib syndrome)
Abnormalities
Bifid ribs and other skeletal abnormalities.
Multiple jaw cysts.
Multiple nevoid basal cell carcinomas.
3. Cleido-cranial dysostosis: large skull with
mental retardation, open fontanells, small
maxilla, high arched palate, absent or
hypoplastic clavicles
Predeciduous Dentition
Hornified structure at birth or just after.
Due to extra-teeth buds.
Most common in lower anterior area.
Present just above the alveolar ridge, so easily removed
Anomalies in eruption of teeth
1. Transposition
Teeth commonly involved
1. Permanent canine and 1st premolar
2. Second premolar (between 6 & 7)
3. Central & lateral incisors
N.B. Transposition was not reported in Pry teeth but may be with hypodontia or supernumerary teeth.
Gemination (twinning)
A single tooth bud divides by an invagination
Fusion
Union of two normally separated teeth.
Theories and types
1- fusion occurs early before calcification:
the tooth formed is one single large
tooth.
2- fusion occurs late after calcification:
there may be union in the roots only
with two separate or single root canal
Concrescence
It is a form of fusion but by cementum only
Taurodontism
Describes the increase in length of the crown on the
expense of root with elongated pulp chamber
so, it shows increase distance between the CEJ and root furcation
Dilaceration
This term refers to an angle or sharp bend either in the crown or root. More in maxillary anterior teeth
Dense-in-Dent
It is due to enfolding of the enamel organ to the
interior during development and before calcification
The most extreme form of this anomaly is referred to
as Dilated odontome
Dense evaginatus
Leong’s premolar
Talon’s cusp
Enamel pearls
Clinical implications of Gemination
- Poor esthetics due to a partially divided tooth.
- Hypoplastic enamel and increased caries
- susceptibility
- Malocclusion and periodontal problems
Differential Diagnosis of Dilaceration
Condensing osteitis,
Idiopathic osteosclerosis.
Fused roots.
Anomalies in Tooth
Structure
**Amelogenesis Imperfecta (AI)
Developmental anomaly that affects enamel formation.
Hypoplastic type. in matrix formation.
Types
1. Hypocalcification (mineralization) occurs due to increased permeability
1. Hypomaturation (Enamel is of normal thickness but with density similar to D)
1. Hypomaturation.
1. Hypocalcifid type (mottled E)
Dentinogenesis imperfecta (DI)
Bulbous teeth, obliteration of pulp, Short blunted roots
Pulp appears more wide then quickly
shows calcification, multiple periapical R L
Osteogenesis imperfecta
Ghost tooth
Turner’s Hypoplasia
Congenital Syphilis
