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 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)
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
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)
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
