Info missed first time paeds Flashcards
What happens during the bud stage?
Migration of neural crest cells
What happens during the cap stage?
Proliferation: Condensation of ectoderm and formation of enamel organ and the dental papilla
What developmental anomalies arise from the cap stage?
Odontogenic cysts
What is morphodifferentiation and which stage of development is it?
Proliferation of inner oral epithelium to form the shape of the crown occurs during the bell stage
Which developmental anomalies and traits are associated with the morphodifferentiation phase of development of the tooth?
Tooth size and shape (macro and microdontia, talon cusps, hutchinson’s incisors/mullberry molars, taurodontism, dens in/evaginatus, cusps of cerebelli)
Which developmental anomalies and traits are associated with the histodifferentiation stage of development?
Regional odontoplasia
What is histodifferentiation and which stage of development is it?
Differentiation of precursor cells -> ameloblasts, odontoblasts depend on secondary enamel knots
What are the stages of crown formation?
Apposition (Reciprocal induction and laying of mantle dentin and first enamel)
Calcification
Maturation (enamel crystal formation)
Eruption (Emergence and continued root development)
Which genes are important for formation of the oral epithelium?
BMP FGF WNT SHH TNF
Which genes are important for formation of the dental placode?
BMP
FGF
WNT
SHH
Which genes are important for formation of the enamel knots during morphogenesis?
BMP
FGF
WNT
SHH
What proteins are required for the ectomesenchyme?
BMP and ACTIVIN
What proteins are required to be expressed for condensed ectomesenchyme?
BMP
FGF
WNT
What proteins are required to be expressed for dental papilla ectomesenchyme?
BMP
FGF
WNT
What are the possible locations of hyperdonts?
Mesiodens (somewhere in premaxilla)
Para(pre)molar
Distomolar (as a 9)
What are the possible morphologies of hyperdonts?
Conical
Tuberculate
Supplemental
Odontomes
What are the types of odontomes?
Compound: Well-circumscribed (Discrete tooth-like structures)
Complex
Clinical signs of odontomes?
Diastema/local crowding/irregularity
Displacement of other teeth
Failure of teeth to erupt
Retention of primary incisors
What conditions are associated with hyperdontia?
Cleidocranial dysplasia
Gardner syndrome
Nance-Horan syndrome
Cleft lip and palate
Ehler-Danlos Syndrome
Fabry-Anderson’s syndrome = X-linked lysosomal storage disorder
Incontinentia pigmenti
Chondroectodermal dysplasia
CGNCEFIC
Which condition leads to hutchinson’s teeth that isn’t syphillis?
Nance-Horan syndrome
What should be done to treat supernumerary teeth?
Surgical complications associated with early or late supernumerary teeth. More
favourable to exo mesiodens etc before age 6 – no association with damage in surgery (even though
some people say “don’t take out too early for fear of damaging tooth germs”)
What environmental factores cause hypodontia?
Intrauterine drugs
Radiotherapy and chemotherapy (if kids have undergone oncology treatment)
Trauma
Infection
What syndromes can lead to hypodontia?
Hypohidrotic ED +/- immunodeficiency
Axenfeld-Rieger syndrome (cataract-dental syndrome)
Clefts
Van der Woude syndrome -> clefting
Down syndrome
Oral-facial-digital syndrome
Williams syndrome
Oligodontia and colorectal cancer syndrome
Odonto-onycho-dermal dysplasia
Incontinentia pigmenti
Ecterodactyly, ectodermal dysplasia
Ellis-van creveld syndrome
Witkop syndrome
Curry-Hall syndrome
Angel-shaped phalango epiphyseal dysplasia
What happens in hypohidrotic ED?
Can cause immunodeficiency
Hidrosis = sweating
What is axenfeld-rieger syndrome?
Predominantly an eye disease - strangely shaped pupils and hypertelorism (Wide eyes)
Leads to microdontia as well as oligodontia
What are the clinical features of hypodontia?
infraocclusion of primary teeth
Increased overbite, tooth rotation, and ectopic maxilalary canines
Reduced mandibular plane angle
How is hypodontia treated?
Build up peg lateral incisors, conical teeth etc
Orthodontic managemetn
Dentures or fixed prostheses
Autotransplants
Implants
What commonly coexists with a primary lateral incisor that has a talon cusp? What does this mean clinically?
A supernumerary tooth
If there is a talon cusp on the primary lateral incisor take an occlusal radiograph.
What syndromes cause talon cusp?
Sturge weber syndrome
Rubenstein-Taybi
Ellis van Creveld (Chondroectodermal dysplasia)
What is Rubenstein-Taybe syndrome?
Condition that causes short stature, moderate to severe intellectual disability, distinnctive facial features, and broad thumbs + First toes.
Small jaws
Crowding
High palate
TALON CUSPS
What causes dens evaginatus to form?
Inner enamel epithelium proliferates into the stellate reticulum due to outflowing of the enamel epithelium, and transient focal hyperplasia of the primitive pulpal mesenchyme.
What causes dens invaginatus?
Due to invasion of dental papilla by a rapid, progressively proliferating area of internal enamel
epithelium
What causes taurodontism?
Unknown but probably linked to failure of hertwig’s epithelial rooth sheath to invaginate.
What anomalies are commonly associated with taurodontism?
Amelogenesis imperfecta
Hypodontia
What is HPSM and what does it mean?
Hypomineralised primary second molars. It means that the child will have 4x more chance of MIH
How should HPSM be treated?
Need to manage fairly aggressively – fissure seal/SS crown asap (esp if brown)
What features of MIH microstructure make it hard to treat?
High levels of TRPV1 receptors which trigger hypersensitivity.
Increased pulpal innervation
These make it difficult to anaesthetize so PDL injections may be necessary.
Higher protein content make bonding difficult
How is MIH treated?
Currently depends on how bad it is. No treatment -> Tooth mousse -> Fluoride varnish -> F/S -> Composite
Resin infiltration is currently used as it penetrates deeper than CPP-ACP. The microporosities fill with resin and then are cured. Follow this up with a Stainless Steel Crown
What is a turner tooth?
Usually result of trauma to dentition before the age of 3 leading to enamel defects.
What is amelogenesis imperfecta?
Hereditary defect of enamel of the permanent and/or primary dentition.
What causes amelogenesis imperfecta?
Can be inherited: X-linked (AMELX), Dominant (Enamelin), and recessive in some families.
What are the classes of amelogenesis imperfecta?
Hypoplastic
Hypomature
Hypocalcified
HM/HP + taurodontism
What clinical considerations to have with AI?
Low caries risk
Rapid attrition
Extensive calculus deposition
Sensitivity
Gingival hyperplasia/inflammation
Non-enamel related factors: Open bite, eruption disturbances, congenitally missing teeth, increased impaction of permanent teeth
Differentials for AI:
Extrinsic disorders such as fluorosis
Chronologic disorders of tooth formation (Extent and number of teeth depends on timing. Not thought to have genetic component)
What are the grades of ectopic eruption of the 1st permanent molar teeth?
Grade 1: Mild, limited resorption of the cementum with minimum dentin penetration
Grade 2: Moderate, resorption of dentin without pulp exposure
Grade 3: Severe, Resorption of the distal root leading to pulp exposure
Grade 4: Very severe, Resorption that affects the mesial root of the primary second molar
What causes ectopic eruption?
Mesial angulation of the 6
Larger than average width of the 6
Crowding
Unfavourable shape of the Es
What is the prognosis of ectopic eruption like?
Can be reversible or irreversible.
Spontaneous correction occurs in 50 - 69%. If permanent molar is blocked distal movement is indicated to create space and correct eruption
When is ectopic eruption of 6s diagnosed?
5 - 7 years of age via radiograph.
