Dental Anomalies Flashcards
What is hypodontia?
Congenital absence of one or more teeth.
What is the most common tooth to be congenitally missing?
Third molar.
Then upper laterals
Mandibular premolars
Which teeth are least likely to be congenitally missing?
First permanent molars and upper centrals.
What conditions are associated with hypodontia?
Ectodermal dysplasia
Down’s syndrome
Cleft lip and palate
Hurler’s syndrome
Incontinentia Pigmentii
What restorative issues can occur in hypodontia?
Over-eruption of canine into upper lateral space
Loss of space- drifting of adjacent teeth
Too much space
Infra-occluded primary tooth if no permanent successor
Abnormal shape and abnormal form
Deep overbite
Reduced LFH
What is the chronology go dental management of hypodontia?
Diagnosis
Removable prosthesis in mixed dentition stage
Orthodontics to open or close spaces +/- restorative work
Composite build ups
Porcelain veneers
Crowns and bridges
Implants
- when the child has stopped growing.
Preventative treatment throughout- don’t want the child losing any more teeth.
Hypotonia children would be classed as high caries risk- follow the enhanced prevention pathway.
What is hyperdontia?
Patient has extra teeth
Where is hyperdontia most common?
In the maxilla
Higher frequency in cleidocranial dysplasia
What are the four types of supernumerary?
Conical- cone shaped
Tuberculate- barrel shaped, has tubercles
Supplemental- looks like a tooth of normal series
Odontome- irregular mass of dental hard tissues
- Compound or complex
What is a microdont?
Smaller than normal tooth/teeth- peg shaped laterals
What is a macrodont?
Larger than normal tooth.
What is the difference between gemination and fusion?
Gemination- tooth splits into two
Fusion- 2 teeth fuse together
What is taurodontism?
Crown is enlarged but the roots are reduced- pulp extends high occlusally.
Flame shaped pulp
What is dilaceration?
Crown or root deviates from the other part of the tooth.
What is an accessory cusp?
Additional cusp found on a tooth- talon cusp.
What is Dens in Dente?
Tooth within a tooth- invaginations within the tooth which have their own pulp system.
Why is prevention important in teeth that are dens in dente?
If bacterial ingress occurs, it is impossible to perform root treatments- only option would be to extract.
Why might a tooth have short roots?
Radiotherapy
Dentine dysplasia
Accessory roots
Ortho treatment
Why might localised enamel hypoplasia have occurred?
Trauma to primary tooth which has impacted the permanent tooth
Infection of the primary tooth
What would be the treatment for localised enamel hypoplasia/hypomineralisation?
Composite restorations.
If someone has generalised enamel hypoplasia, what is it important to determine?
If the cause is environmental or hereditary.
What causes might cause generalised environmental enamel hypoplasia?
Fluorosis- symmetrical, diffuse white patches on the teeth, some patients may have brown patches.
- treat with micro abrasion/veneers/ vital bleaching
MIH- molar incisor hypo mineralisation
What periods of development might cause a generalised enamel defect?
Prenatal- rubella, congenital syphillis, thalidomide, cardiac and kidney disease, drug use
- focussing on the pregnancy
Neonatal- prematurity, meningitis, difficult delivery (starved of oxygen).
Postnatal- otitis media, measles, chickenpox, TB, pneumonia, diphtheria, long term heart problem.
- focus on first year of life.
What cause could be generalised hereditary?
Amelogenesis Imperfecta
What are the 4 types of Amelogenesis Imperfecta?
Hypoplastic
Hypomineralised
Hypomaturation
Mixed with taurodontism
Describe the 4 types of Amelogenesis Imperfecta.
Hypoplastic- enamel crystals do not grow to the correct length
Hypomineralised- crystallites fail to grow in thickness and width
Hypomaturational- enamel crystals grow incompletely in thickness or width but normal length with incomplete mineralisation.
What gene mutations are found in Amelogenesis Imperfecta?
Kalikrein 4
Enamelin
Enamel extracellular matrix molecules amelogenin
How would you diagnose Amelogenesis Imperfecta?
Ask about family history- hereditary
Generally affects both dentitions- but worse in the permanent dentition
Affects all teeth
Affects tooth size, structure and colour
Radiographs- fail to see an obvious radiolucency between enamel and dentine.
What are the potential problems in amelogenesis Imperfecta?
Sensitivity- no hard enamel over the dentine, can lead to poor PH if it is sore to brush.
Caries/acid susceptibility
Poor aesthetics
Poor oral hygiene
Delayed eruption
Anterior open bite
What solutions may be available to combat the problems seen in Amelogenesis Imperfecta?
Enhanced prevention
- fluoride varnish, bond, composite for sensitivity.
Composite veneers
Fissure sealants
SSC
Orthodontics
What systemic disorders are associated with enamel defects (not amelogenesis imperfecta)?
Down’s syndrome
Prader Willi Syndrome
Porphyria
Epidermolysis Bullosa
What is Dentinogenesis Imperfecta?
Hereditary disorder of dentine development and formation.
What are the 3 types of dentinogenesis Imperfecta?
Type I- osteogenesis Imperfect (issues with bones as well)
Type II- autosomal dominant- patient tends to not have any underlying medical conditions, only DI.
Brandywine.
How would you diagnose Dentinogeneis Imperfecta?
Teeth appear abnormal shape and darker colour.
Ask about family history
Associated with osteogenesis imperfecta- wheelchairs, multiple bone fractures, blue sclera of the eye
Affects both dentitions
Radiographs- bulbous crowns, obliterated pulps, abscess formation.
Enamel loss
What problems might arise from dentinogenesis Imperfecta?
Aesthetics
Caries/acid susceptibility
Spontaneous abscess
How would you combat the problems seen in Dentinogenesis Imperfecta?
Prevention
Composite veneers
Over dentures
RPD
Stainless steel crowns
What other hereditary dentine defects can occur?
Dentine dysplasia type I and type II
Fibroud dysplasia of dentine
What other hereditary dentine defects can occur that are associated with a general disorder?
Ehler’s Danlos syndrome
Osteogenesis Imperfecta
Rickets
Hypophosphatasia
What might cause premature eruption of teeth?
Neonatal/natal tooth
High birth weight
Precocious puberty
What might cause delayed eruption of teeth?
Malnutrition
Pre-term and low birth weight children
Down’s syndrome, hypothyroidism, cleidocranial dysplasia.
Gingival hyperplasia
Why might neonatal/natal teeth need to be extracted?
Inhalation risk
Issues with feeding
Why might premature exfoliation occur?
Trauma
Following pulootomy
Hypophosphatasia
Immunological deficiency- cyclic neutropenia
Why might there be a delay in exfoliation?
Trauma to primary tooth
Ectopic succesor
Lack of successor- hypodontia
Infra-occlusion
“Double” primary teeth
