dental anomolies 1 Flashcards
Enamel defects
Ameloblasts sensitivity?
Enamel defects may be caused by what factors?
Enamel remodeling?
Abnormalities etched?
Enamel defects
Ameloblasts: extremely sensitive to external stimuli
Enamel defects may be caused by local or systemic factors
Enamel remodeling does not occur after initial formation
Abnormalities etched permanently on tooth surface
Stages of enamel development
1) Matrix formation: enamel proteins laid down
2) Mineralization: minerals deposited, original proteins removed
3) Maturation: final mineralization, remaining original proteins removed> Hard, translucent enamel
Enamel defects
Timing of injury: affects?
Final enamel: record of?
Timing of injury: affects location and appearance of defect
Final enamel: record of all significant insults received during toothdevelopment
Enamel hypoplasia
large areas of missing enamel
Pits, fissures, grooves
enamel opacities
areas of enamel hypomaturation
diffuse or demarcated
White, yellow, brown
enamel hypoplasia of a systemic cause due to more generalized app
enamel opacities
turner hypoplasia
Clinical and Radiographic features:
Observed in which tooth? MC?
Traumatic cases?
app?
Extensive hypoplasia may involve?
RG?
Periapical inflammatory disease or trauma of overlying deciduous tooth
Clinical and Radiographic features:
Observed in permanent teeth – MC premolar
Traumatic cases – max central incisors
Focal areas of white, yellow, brown discoloration
Extensive hypoplasia – may involve entire crown
RG: lack of enamel, irregular surface dentin
severity of turner hypoplasia depends on?
timing on development, earlier= more severe
Antineoplastic therapy and development
Severity dependent on?
which is more severe?
Developmental abnormalities secondary to use of radiation orchemotherapy
Severity dependent on age of treatment, form of therapy, dose and field ofradiation
Radiation therapy – more severe alterations
Antineoplastic therapy
Clinical features:
Radiation:
Chemotherapy:
Radiation: Hypodontia, microdontia, radicular hypoplasia, enamel hypoplasia
Chemotherapy: enamel hypoplasia, microdontia, occasionally radicular hypoplasia
what previous medical tx likley occurred in this pt
antineoplastic tx
Dental Fluorosis
Ingestion of?
mechanism?
Dose?
Ingestion of excessive FL → significant enamel defects
Retention of amelogenin proteins in enamel → hypomineralized enamel
Dose dependent
fluorosis clinical features
color?
caries?
distribution?
White, opaque enamel, with areas of brown/yellow discoloration
Affected teeth are caries resistant
Bilateral, symmetrical distribution
fluorosis
Treatment: enamel defects
most defects are?
focal lose of enamel may lead to?
options?
Most defects are cosmetic
Focal loss of enamel – increased prevalence of caries
Composite restorations, veneers, full crowns
Tooth wear
Considered pathologic when?
Considered pathologic when the degree of destruction creates functional, aesthetic, or dental sensitivity problems
Attrition
Loss of tooth structure due to?
what can accelerate process?
Loss of tooth structure due to tooth-to-tooth contact
Poor-quality/absent enamel can accelerate process
attrition clinical features
Incisal and occlusal surfaces
Large, flat, smooth and shiny wear facets
Slow loss of tooth structure, reparative secondary dentin forms
Abrasion
defined?
MC agent
Pathologic wearing of tooth structure secondary to an external agent
Toothbrushing MC
abrasion clinical features
Clinical features:
Dependent on?
Toothbrushing?
additional causes?
Dependent on cause
Toothbrushing: horizontal cervical notches on buccal surface
Tobacco pipe, bobby pins: V-shaped notches on incisal edge
Erosion
Loss of tooth structure caused by?
Exposure to?
Loss of tooth structure caused by a non-bacterial chemical process
Exposure to acidic source, reduced salivary flow
erosion Clinical features:
Cupped lesion, central depression of dentin surrounded by elevated enamel
May create concave sloping areas on palatal surfaces
Tooth wear treatment
cause?
Detailed?
Erosion: may consider?
Restorative treatments?
Tooth wear treatment
Multifactorial cause
Detailed diagnosis, preventative measures
Erosion: may consider limiting toothbrushing 1x daily
Restorative treatment: composite, veneers, full crown
Extrinsic stains
Arises from?
Usually can be removed with?
examples?
Arises from the surface accumulation of exogenous pigment
Usually can be removed with surface treatment
Tobacco, bacterial stains, food + beverages, iron, restorative materials,medications
Intrinsic stains
Arises from?
Cannot be?
examples?
Arises from endogenous materials that are incorporated into enamel and dentin
Cannot be removed by prophylaxis
Amelogenesis imperfecta, dentinogenesis imperfecta, dental fluorosis, hyperbilirubinemia, trauma, medications
Internal Resorption
Loss of tooth structure on?
Commonly arises secondary to?
Continues if?
Loss of tooth structure on the dentinal walls of the pulp
Commonly arises secondary to inflammatory reaction
Continues if vital pulp tissue remains
forms of internal resorb
inflammatory and replacement
inflammatory internal resorb clinical and radio features
resorbed dentin replaced by inflamed granulation tissue
RG: well-circumscribed radiolucent enlargement of pulp chamber
replacement internal resorb clinical and radio findings
pulpal dentinal wall is resorbed with bone and
cementum-like bone
RG: partial obliteration of canal by bone (radiopacity)
pink tooth of mummery
occurs when coronal pulp is affected by internal resorb
internal resorbtion (inflammatory)
External resorption
Loss of?
Exposure of?
Common causes:
Commonality vs internal?
Loss of tooth structure along external surface of root
Exposure of adjacent mineralized cementum to cemetoclasts
Common causes: localized pressure (ie: orthodontic therapy), excessive occlusal forces, cysts, tumors
More Common!
External resorption
Clinical and Radiographic findings:
“moth-eaten” loss of tooth structure
Over pulp chamber, radiolucency superimposed
external resorbtion
Ankylosis
Anatomic fusion of?
May be caused by?
Anatomic fusion of tooth cementum with the alveolar bone
May be caused by trauma, chemical/thermal irritation, genetically decreased PDL
Ankylosis
Clinical features:
MC age?
MC tooth?
Mandible vs maxilla ratio
Ankylosis of permanent teeth?
percussion?
Clinical features:
MC 1st-2nd decade
MC mandibular primary first molar
Mandible 10:1
Ankylosis of permanent teeth uncommon
Sharp, solid sound upon percussion
Ankylosis
Radiographic features:
Absence of PDL space (difficult to detect)
Adjacent teeth inclined towards affected tooth
Supraeruption of opposing tooth
ankylosis tx
For primary teeth (lack of exfoliation) → extraction
what can be noticed?
ankylosis of the primary molar
Tooth number anomalies
Anodontia:
Hypodontia:
Oligodontia:
Hyperdontia:
Anodontia: total lack of development of teeth
Hypodontia: lack of development of one or more teeth
Oligodontia: lack of development of 6 or more teeth
Hyperdontia: development of an increased # of teeth – supernumerary
Tooth number anomalies
More than ___ genes associated with odontogenesis
Syndromic or non syndromic?
MC genes implicated:
More than 200 genes associated with odontogenesis
Syndromic and non syndromic
MC genes implicated: PAX9, MSX1, AXIN2 genes (hypodontia)
Hypodontia
Prevalence of ?% in permanent teeth
what correlates strongly with missing successor?
Syndrome associated:
Prevalence of 3-10% in permanent teeth
Absence of primary teeth correlates strongly with missing successor
Syndrome associated: Ectodermal dysplasia
Hypodontia
Clinical features:
MC teeth?
MC sex
After 3rd molars, MC in 2nd premolar and lateral incisor
MC in females
AMLI
Hyperdontia
Most cases represent?
Syndromes:
Positively correlated with?
Most cases represent single-tooth supernumerary
Syndromes: Cleidocranial dysplasia, Gardner
Positively correlated with macrodontia
Hyperdontia
Clinical features:
Single tooth hyperdontia: MC in?
Accessory 4th molar?
sex ratio
Single tooth hyperdontia: MC in anterior maxilla – mesiodens
Accessory 4th molar: distomolar/distodens
2: 1 male
Microdontia
Presence of?
factors playing a role?
Conditions:
Isolated cases vs diffuse cases?
Presence of unusually small teeth
Genetic and environmental factors play a role
Conditions: Down syndrome, pituitary dwarfism
Isolated cases more common than diffuse cases
Microdontia
Clinical features:
Isolated microdontia: MC in?
MC sex
Isolated microdontia: MC in max lateral – peg lateral
MC in females
Macrodontia
Teeth size?
factors playing a role?
Conditions:
Isolated cases vs diffuse
Teeth larger than average
Genetic and environmental factors play a role
Conditions: pituitary gigantism, XYY, pineal hyperplasia, hyperinsulinism
Isolated cases more common than diffuse cases
Macrodontia
Clinical features:
Isolated macrodontia: MC in
MC sex
Isolated macrodontia: MC in incisors or canines
MC in males
