Developmental Anomalies and Developing Dentition

when r the first signs of tooth development

6 weeks

localised epithelial thickening in incisor and molar regions

inititiated by epithelium - that has odontogenic potential and then ectomesenchyme

what is jowett et al

MSx1 and MSx2 has to be switched on to make a tooth

what is hypodontia

absence of teeth due to failure of development

anodontia - total lack of teeth in 1 or 2 dentitions

oligodontia - more than 6 teeth missing primary or perm

what teeth are most likely to be missing

8s then lower 5s then upper 2s then upper 5s

more likelt if missing primary teeth then they will be more likely be missing permanent

what is the aetiology of hypodontia

usually uncealr

likely genetic - autosomal dominant inheritence pattern in some families

occasioanlly envurinmental insult

associted with certain syndromes - ectodermal dysplasia or downs

what is autosomal dominant

if they have a dominant gene it will be presented but if it is recessive then both genes r needed

what is supernumery teeth

Development of one or more extra teeth

mesiodens - in midline usually peg shape teeth

supplemental - normal teeth

conical supernumaries - look like a cone and they can erupt but they can migrate up

tuberculate - dont migrate but can impade eruption of adjecent teeth

what is microdontia

small peg shape teeth

lateral incisors most affected

what is macrodontia

big teeth

double teeth - 2 crowns

dens in dente - invagination

talon cusps - evagination

what is doubl teeth

fusuion - abnromal shape resulting from fusion of 2 seperate tooth germs

gemination - 2 teeth develop from one tooth germ look abnormally wide

can distinguish between no of roots and if there is missing teeth - fusion means less teeth

what is dense in dente

tooth wihtin a tooth

localised area of the vrown is folded inwards

what is a talon cusp

evagination

can have iys own pulp and nerve so hard to do

what is amelogenesis imperfecta

effects emalogenesis cycle - affects ameloblast function

affects both primary and perm dentition

2 types - hypomineralised (weak enamel) hypoplastic ( thin but hard)

what do dentinogenesis imperfecta present as

poor OH

pain and infection w necrosis

dentine exposure

enamel breakage

what are non hereditary distrurbances in teeth

what is Molar incisor hypomineralisation

developmental defect in enamel structure

typically 1st perm molars and incisors but can be others

very common - 20%

demarcated enamel opacities and can be from white to yellow/brown

can appear hypoplastic

ot can be axious and fail tx etc

LA is less effective !

what is flourosis

high F conc during amelogenesis

irregular enamel opacities

what is turners tooth

affects successional tooth

allegedly hypoplastic