Dental Anomalies Flashcards
You can get dental anomalies associated with what?
-number
-size and shape
-structure - hard tissue defects
-eruption and exfoliation
What are the anomalies of number?
-hypodontia
-supernumerary/hyperdontia
How common is hypodontia in primary dentition?
0.1-0.9%
Most common tooth missing? (apart from 8s)
mandibular premolars (then maxillary lat incisors)
What teeth are the least likely to be missing?
FPM
Upper central incisors
Note: in mandible more likely to have central incisor missing than lat because of genetic programming
What are some conditions associated with hypodontia?
-ectodermal dysplasia (sparse hair, intolerance to sweating)
-Down syndrome
-cleft palate
-hurler’s syndrome
-incontinentia pigmentii
When might you use an overdenture in a case of hypdontia?
submergence (infra-occluded) primary teeth
With missing upper lateral incisors, what might be a problem relating to the lower dentition?
-overeruption of lower canine
-might want to try prevent this
What are the aims when treating hypodontia?
-prevention of further tooth loss
-aesthetics
-function
What are some problems associated with hypodontia that can affect management?
-abnormal shape and form of teeth
-spacing
-submergence
-deep overbite
-reduced LFH
What are some tx options for hypodontia?
-overdenture
-partial denture
-composite
-porcelain veneers
-fixed prosthesis
-implants
What is the prevalence of hyperdontia/supernumerary teeth? What sex is it more common in?
1.5-3.5% prevalence
more common in males 2:1 ratio
Are supernumary more common in the madible or maxilla?
maxilla
What medical condition is hyperdontia/supernumary teeth more common in?
cleidocranial dysplasia
What are the different types of supernumerary teeth? Describe shape.
Conical - cone shaped
Tuberculate - barrel shaped, has tubercles
Supplemental - looks like tooth of normal series
Odontome - irregular mass of dental hard tissue, compound or complex
Suppernumerary teeth are the most common cause of what?
Delayed eruption of permanent incisor teeth (normally maxillary lateral incisor)
Would you remove this conical supernumerary now? Why?
No because it is too close to other developing crowns.
Would wait until full crown formation and can begin to see root formation
What anomalies of shape and size can you get?
-microdont
-macrodontia (rare)
-double teeth
-odontomes
-taurodontism
-dilaceration (crown or root)
-accessory cusps e.g. talon cusp
What is an example of a microdont? Is it common?
Peg lateral incisors
2.5% prevalence
What are the 2 different types of ‘double teeth’? How do you tell the difference?
-gemination (one tooth splits into 2)
-fusion (two teeth join to form 1)
Difficult to tell the difference so the term double teeth/tooth is fine
What is taurodontism? How common? What is the issue?
-Flame shaped pulp (looks like bulls horns - tauro)
-exposing pulp when restoring more likely
-6.3% in UK
What is a talon cusp and how would you tx?
-extra cusp that has grown
-would do selective grinding over time and put Fl- on (encourages pulp tissue to shrink back)
-composite on front of tooth to make it look more normal
What is dens in dente? What is the issue with them?
‘tooth within a tooth’
Invagination in the teeth which also have their own pulp system
Are impossible to root treat (prevention vimportant!)
What anomalies can you get of the root structure?
-short root anomaly
-radiotherapy???
-dentine dysplasias
-accessory roots
What is the most common tooth affected by a short root anomaly? Why are short root anomalies an issue in general?
-permanent max incisors
-danger point for ortho
What are the 3 anomalies of the structure of enamel?
-amelogenesis imperfecta
-environmental enamel hypoplasia
-localised enamel hypoplasia
What are examples of localised enamel hypoplasia? (causes)
-trauma
-infection of primary tooth
What are some of the different forms of amelogenesis imperfecta?
-hypoplastic
-hypocalcified
-hypomaturational
-mixed forms
Note: there are actually hundreds of forms but need to know these ones
What are some examples of causes of environmental enamel hypoplasia?
-systemic (kidney failure, liver failure)
-nutritional (nutrition not right when dentition is developing)
-metabolic (e.g. rhesus incompatibility, liver disease)
-infection (e.g. measles)
What is the difference between hypomineralised enamel and hypoplasia?
In hypomineralised:
-all tooth tissue is there
-normal tooth shape, just marks on the teeth
-Enamel secretory phase has been normal but mineralisation stage has been faulty
Hypoplastic/hypoplasia:
-would be chunks missing from the tooth
-happens at a different stage of amelogenesis (earlier stage than hypomineralisation - secretory)
-quantitive problem, not qualitative
When looking at hard tissue defects, how should you be thinking about them? (flowchart to catergorise)
-localised or generalised? (all teeth? both dentitions?
-environmental or hereditary?
What are localised hard tissue defects due to?
-trauma
-caries then abscess of primary incisors (then impacted permanent incisor/tooth)
What are examples of generalised environmental hard tissue defects?
-fluorosis
-MIH (molar incisor hypomineralisation)
-hypoplasia
When might you see lines of hard tissue defects across the permanent dentition? (Why?)
When you have MIH/hypoplasia etc associated with childhood illness (chronological hypomineralisation) e.g. liver failure, kidney failure
Can see when the pt was ill during formation of enamel
When ill the enamel hasn’t formed or mineralised correctly but when well it has formed as normal
With generalised environmental enamel defects, you want to ask questions around what periods?
Same as with MIH:
-prenatal
-neonatal (up to 8wks after birth)
-postnatal (from 8wks to 1-2yrs)
For generalised environmental enamel defects, what questions/things are you thinking about for the prenatal period?
-rubella
-congenital syphilis
-thalidomide
-fl_
-maternal A&D deficiency
-cardiac and kidney diseases
For generalised environmental enamel defects, what questions/things are you thinking about for the neonatal period?
-prematurity
-meningitis
For generalised environmental enamel defects, what questions/things are you thinking about for the postnatal period?
-otitis media
-measles
-chickenpox
-TB
-pneumonia
-diptheria
-deficiency of vits A, C and D
-heart disease
-long term health problems e.g. organ failure
What is an example of a generalised hereditary hard tissue defect?
Amelogenesis imperfecta
What are the 4 main types of amelogenesis imperfecta?
-hypoplastic
-hypomineralised
-hypomaturation
-mixed with taurodontism (flame-shaped pulps)
What is the associated familial inheritance?
can be autosomal dominant, recessive and x-linked
no associated systemic disorder
What things (signs/symptoms) help with the diagnosis of amelogenesis imperfecta?
-fam hx
-generally affects both dentitions
-affects all teeth
-tooth size, structure and colour all affected
-radiographs
What will radiographs show in amelogenesis imperfecta?
-fail to see an obvious change in radiolucency between the enamel and dentine
Enamel formation needs multiple genes to do what?
Transcribe the process of crystal growth and mineralisation
Gener mutations found in amelogenesis imperfecta so far involve what?
-enamel extracellular matrix molecules amelogenin an enamelin and kallikrein 4
Describe hypoplastic amelogenesis imperfecta.
-enamel crystals do not grow to the correct length
Describe hypomineralised amelogenesis imperfecta.
Crystallites fail to grow in thickness and width
Describe hypomaturational amelogenesis imperfecta
-enamel crystals grow incompletely in thickness or width but to normal length with incomplete mineralisation
What problems are associated with amelogensis imperfecta?
-sensitivity (don’t have same enamel protecting dentine and pulp)
-caries/acid susceptibility
-poor aesthetics (brown colour an white flecks)
-poor OH
-delayed eruption
-anterior open bite (vcommon malocclusion with this)
What are some tx options for amelogenesis imperfecta?
-preventive therapy
-composite veneers/composite wash (helps w/ sensitivity and appearance)
-fissure sealants
-metal or ceramic onlays
-stainless steel crowns
-orthodontics (bonding systems don’t work well as need to bond to enamel so brackets debond)
What systemic disorders are associated with enamel defects? (not amelogenesis imperfecta)
-Downs syndrome
-Prader-Willi
-epidermolysis bullosa
-incontinenta pigmenti
-tuberous sclerosis
-Hurler’s
-porphyria
What are the 4 anomalies of dentine structure?
-dentinogenesis imperfecta
-dentine dysplasia
-odontodysplasia
-systemic disturbance
What is dentine dysplasia?
Genetic disorder associated with the structure of dentine causing:
-normal crown morphology
-amber radiolucency
-pulpal obliteration
-short constricted roots
-discolouration
What is odontodysplasia/describe it
-localised arrest in tooth development
-are thin layers of enamel and dentine
-have larger pulp chambers
-‘ghost teeth’
What systemic disturbances might cause problems with the dentine structure when the teeth are forming?
-nutritional
-metabolic
-drugs
What are the 3 types of dentinogenesis imperfecta?
-Type I (osteogenesis imperfecta)
-Type II (autosomal dominant - no underlying coniditons)
-Bradywine
What things aid in diagnosis/are signs of dentinogenesis imperfecta?
-appearance
-fam hx
-associated osteogenesis imperfecta (tend to be in wheelchairs, multiple bone fractures)
-both dentitions affected
-radiographs
-enamel loss (lost quickly as no proper connection at ACJ)
What will you see in radiographs of people with dentinogenesis imperfecta?
- bulbous crowns, obliterated pulps (I and II)
Why is type III Bradywine dentinogeneiss imperfecta called this?
Originated from USA and places where there was incest and now a genetic disorder causing it
What are some of the problems associated with dentinogenesis imperfecta?
-aesthetics
-caries/acid susceptibility
-spontaneous abscess
-POOR PROGNOSIS
-very difficult to tx
What are some solutions/tx options for dentinogenesis imperfecta?
-prevention
-composite veneers
-overdentures (to cover over the unprotected vulnerable dentine)
-removable prostheses
-stainless steel crowns
What heriditary dentine defects are limited to dentine only? (not associated with a general disorder)
-dentinogenesis imperfecta type II
-dentine dysplasia types I and II
-fibrous dysplasia of dentine
What heriditary general disorders are associated with dentine defects?
-osteogenesis imperfecta
-rickets
-ehlers-danlos syndromw
-brachio-skeletal genital syndrome
-hypophosphatasia
For tooth structure defects in general, what are you trying to do? (in a child)
-prevention and pain control
-restoration of lost tissue
-harness growth
Give an overview of the dental management of tooth structure defects
What are some anomalies of the structure of dentine?
-cleidocranial dysplasia
-hypophosphatasia
What is cleidocranial dysplasia
-syndrome with no clavicle
-hypoplasia of cellular component of cementum
What is hypophosphatasia?
-hypoplasia or aplasia of cementum
-early loss of primary teeth (nothing holding teeth into the bone)
What are some reasons for premature eruption?
-high birth weight
-precocious puberty
-natal/neonatal teeth
What are some reasons for delayed eruption?
-pre-term and low birth weight children
-malnutrition
-associated general conditions (downs, hypothyridism, hypopituitarism, cleidocranial dysplasia)
-gingival hyperplasia/overgrowth (are erupting but can see due to the overgrowth)
What are some reasons for premature exfoliation of primary teeth?
-trauma
-following pulpotomy
-hypophosphatasia
-immunological deficiency
-Chediak-Higashi syndrome
-Histiocystosis X
What are some reasons for delayed exfoliation of teeth?
-infra-occlusion
-‘double’ primary teeth
-hypodontia (no perm successor)
-ectopic permanent successor
-following trauma
