Dental Anomalies

Question 1

Hyperdontia:

• perm v primary? prevalence? ethnicity?
• Where ? how many?

Answer 1

• 5x more common in the permanent dentition (~4%),
• Blacks/Asians»»Whites
• 95% in maxilla, esp anterior region
• 80% are single tooth

Question 2

Syndromes associated with hyperdontia?

Answer 2

Downs, CL/P
Cleidocranial dysplasia, 
Fabry's Gardner, Hallerman-Strief, 
Sturge-Weber, 
Crouzons and Aperts
orofacial digital syndrome I and III
Ehlers Danlos, incontentia pigmenti

Question 3

Hypodontia:

• perm v primary? prevalence? gender? frequency per tooth?
• Genetics and etiology

Answer 3

Prevalence :

• permanents ~10% w/o 3rd molars. Primary <1%)
• AD/polygenic multifactoral
• Failures arise from (4): Failure of induction, abnormal lamina, insufficient space, physical obstruction of lamina

Question 4

Syndromes associated with Hypodontia

Answer 4

Downs
Ectodermal dysplasia, achondroplasia
Crouzon, orofacial digitial 
Hurler syndrome, Williams, Gorlin
Hallerman strief, Rieger Focal dermal hypoplasia, incontinetia pigmenti

Question 5

Dentin Dysplasia Type I : What kind of teeth?? what is the pathophys, clinically and radiographically what occurs? differences in primary and perm dentition?

Answer 5

Dentin Dysplasia type I: ROOTHLESS TEETH

• length of the rooth depends on when disorganization begins to occur
• multiple abscesses/PARs, crescent shaped pulps or pulp stones if disorg occurs later (dentin is so disorganized, little threads of pulp make their way to the surface, leading to abscesses)
• primary teeth are uniform, perm teeth are variable
• *DD1 ROOTLESS CRESCENTS

Question 6

Dentin Dysplasia Type II : What kind of teeth?? what is the pathophys, clinically and radiographically what occurs? differences in primary and perm dentition?

Answer 6

Dentin Dysplasia type II: is very similar to detinogenesis imperfecta type II

• Clinically, teeth look normal and do not have abscesses or PARs on radiograph
• primary dentition: amber colored, bulbous, thin roots and early PCO
• Perm: normal color, THISTLE pulps and multiple pulp stones

Question 7

What is a third condition similar to dentin dysplasia? What does it look like and why is it different?

Answer 7

Pulpal dysplasia

• looks like dentin dysplasia type II, clinically teeth are normal but on radiograph see thistle shaped pulp chambers w/multiple pulp stones (same as DD type II)
• EXCEPT this is the same in both the primar and permanent dentition whereas in dentin dyplasia type II only see this in permanet dentition and amber colored thin rooted PCO teeth in the primary dentition

Question 8

What are the differences between Dentin Dyplasia type 2 and Dentinogenesis type II?

Answer 8

• In DD 2 the pulp chambers do not fill in before eruption.
• DD 2: crowns are normal shape/size, in DI they are bell shaped with cervical constriction
• DD roots are thin in DI they are also thin but narrow and short