Dental Anomalies Flashcards
give 3 conditions to do with anomalies of the number of teeth
- hyperdontia
- hypondontia
- retained primary teeth
what is hyperdontia?
when you have supernumerary teeth
what 3 conditions may hyperdontia be associated with?
- cleidocranial dysotosis
- gardener syndrome
- cleft lip and palate
what is hyperdontia Mesiodens?
a supernumerary tooth present in the midline between the two central incisors
4 indications of Mesiodens.
- malocclusion
- food impaction
- poor aesthetic
- cyst formation
what is hypodontia? aetiology
absence of the teeth
- obstruction of the dental lamina
- lack of space for development
- failure of initiation of the mesenchyme
which teeth are most affected by hypodontia?
permanent teeth
3rd molar
2nd mandibular premolar
max lateral incisor
define oligodontia
more than 6 teeth missing
define anodontia
complete loss of dentition
what problem can a retained deciduous tooth cause?
it can prevent successor eruption of the permanent tooth
what is fusion?
when a supernumerary tooth is fused
what is gemination?
when a tooth begins to separate into two
what are the two forms of size anomalies?
macrodontia
microdontia
which tooth is likely to have macrodontia
most likely maxillary central incisors
which 3 conditions may be associated with macrodontia?
pituitary gigantism
craniofacial dystosis
congenital facial hemihypertrophy
which tooth is likely to have microdontia?
maxillary lateral incisor
what 2 conditions can be associated with microdontia?
downs syndrome
ectodermal dysplasia
give 4 anomalies in which teeth can have different shape.
- gemination
- fusion
- dens evagintus - enamel pearl
- dens invagintus - infolding of enamel and dentine
what is dens evaginatus?
enamel tubercule extends from occlusal surface
give 3 anomalies of tooth structure.
- amelogenesis imperfecta
- dentinogenesis imperfecta
- molar-incisor hypo mineralisation
what is the aetiology of amelogenesis imperfecta?
genetic mutation in matrix protein coding genes
3 forms of oral presentation from amelogenesis imperfecta. describe them.
hypoplastic
- pitted discoloured enamel
- prone to caries and attrition
- open bite
hypocalcification and hypomaturation
- discoloured soft enamel
- easy to chip and break under mastication
what are the types of dentinogenesis imperfecta? describe what mutation causes them.
type 1
- associated with osteogenesis imperfecta
- mutation in COL1A and COL2A
type 2
- more common
- mutation in gene encoding DSPP
type 3
- familial
- mutation in gene encoding DSPP
state and describe the two types of dental dysplasia.
type 1
- crown is normal
- both dentitions affected
- roots are sharp
- incomplete pulp obliteration
- extreme tooth mobility and premature exfoliation
type 2
- primary dentition is mostly affected
- permanent have thinner roots
- may have pulpal stones
what is Molar Incisor Hypomineralisation?
enamel is very soft
- chips and discolours
- prone to caries
give 2 systemic syndromes associated with dental anomalies.
- ectodermal dysplasia
- cleidocranial dysostosis
define ectodermal dysplasia. aetiology and presentations
primary defect in the development of 2+ tissues derived from embryonic ectoderm
aetiology
- inherited
- involves skin and teeth
presentations
- soft, discoloured enamel
- small, peg shaped teeth
- roots - abnormal shape
- missing teeth
- xerostomia
- underdeveloped alveolar bone
describe what cleidocranial dysostosis is. aetiology and presentations.
aetiology
- mutation of RUNX-2
presentations
- underdeveloped or absent collar bone
- late closure of skull fontanelles
- high vaulted palate
- may have clefts
- short stature
- osteopenia and osteoporosis
- hearing loss
