teeth abnormalities Flashcards
____________ is defined as “Incomplete or defective enamel formation”
Enamel Hypoplasia
what are the 4 causes of Enamel Hypoplasia?
- Turner hypoplasia
- anti-neoplastic agents
- fluorosis
- syphilis
what is attrition? what is abrasion?
Attrition: “Physiological” wear due to tooth to tooth contact during occlusion
Abrasion: Tooth structure loss secondary to external agent; variety of patterns
(ex – toothbrush abrasion)
what is Erosion? what is Abfraction?
Erosion: Cupped-out depression of occlusal surfaces or cusp tips; associated with regurgitated gastric acid or dietary acid
Abfraction: Wedge-shaped defect limited to cervical area; bruxism associated
what are the treatments for attrition, abrasion, erosion, and abfraction?
1) Early diagnosis and intervention
2) Construction of mouth guards
3) Inform patients regarding tooth loss from acidic foods, reflux, etc.
4) Lost tooth structure- replaced with variety restorative procedures
what is internal resorption? what color do effected teeth appear?
internal resorption = Destruction of tooth structure accomplished by cells located in the dental pulp
* teeth may appear pink*
what is the treatment for internal resorption?
Endo therapy prior to perforation
once communication with PDL, poor prognosis
________________ is defined as: Destruction of tooth structure accomplished by cells located in the PDL
external resorption
what are some of the causes of external resorption?
chronic inflammation cysts neoplasms trauma re-implantation of avulsed teeth impactions orthodontic forces idiopathic.
“extrinsic” tooth stains are caused by a surface accumulation of _________________ which can typically be removed by prophylaxis
exogenous pigment
what causes INTRINSIC stains?
Endogenous material is incorporated into developing teeth
what are the 2 major causes of internal staining?
drugs (tetracycline)
blood pigments (Rh incompatibility)
Erythropoietic porphyria can cause what tooth abnormality?
intrinsic staining
- teeth appear blood red
what is the most common dental DEVELOPMENTAL abnormality?
Hypodontia
uncommon in deciduous dentition
Hypodontia in deciduous dentition is stronly associated with what?
a missing succcessor (permanent) tooth
list the most commonly missing permanent teeth:
Third molars > second premolars > lateral incisors
what is Oligodontia?
lack of 6 or more teeth
Hyperdontia occurs in what % of the population?
Occurs in 1-3% of the population
is hyperdontia is more frequent in primary or secondary dentition?
more prevelant in permanent (secondary)
where is hyperdontia most common?
MAXILLARY ARCH (95%)
- more common in the anterior
Mesiodens; distodens; paramolar are all examples of what condition?
Hyperdontia
why can hyperdontia be problematic? when should treatment (extractions) be considered?
May affect occlusion, hygiene; may be unesthetic
removal may be indicated to avoid complications related to normal eruption and occlusion
t/f: microdontia can effect the shape of teeth
true
what teeth are most commonly effected by microdontia?
maxillary laterals (peg) and third molars
t/f: macrodontia is more common than microdontia
FALSE
microdontia is more common, macro is rare
what is Gemination?
Partial division of single tooth bud; crown appears split
where is gemination typically seen?
anterior teeth
during fusion, teeth share _______ and _________, but have separate root canals
cementum and dentin
would gemination or fusion give you the same amount of teeth per arch?
gemination
fusion would give you one less
how would you differentiate between fusion and gemination in a clinical setting?
count the teeth
if they’re missing a tooth- its fusion
______________ is characterized by the fusion of two teeth by cementum alone
Concrescence
where is Concrescence more commonly found?
posterior maxilla
when does concrescence become clinically significant?
Clinically significant if one of the involved teeth must be extracted
what is a talon cusp?
- Rare condition that primarily affects the maxillary incisors
- Basically an exaggerated cingulum
why must treatment for talon cusps be gradual?
gradual removal to allow for secondary dentin formation
____________ is the term given for when there is an extra cusp in central developmental groove
Dens Evaginatus
which teeth are primarily effected by Dens Evaginatus?
Premolar teeth most commonly affected
mandibular predominance
what happens to teeth with dens evaginatus?
Tooth often becomes non-vital, presumably due to attrition or trauma to cusp
what is another name for “Dens Invaginatus”
dens in dente
Dens invaginatus primarily effects which teeth?
maxillary laterals
what is the most likely cause of Dens invaginatus (dens in dente)?
invagination of tooth bud during development
what happens to most teeth with dens invaginatus?
Affected tooth often becomes non-vital shortly after eruption
where are enamel pearls commonly found?
Furcations of maxillary or mandibular molars
T/F: Enamel Pearls may have dentin and pulp horns
true
what is the main concern with enamel pearls?
May be detected by probing, if mistaken for calculus, can lead to pulp exposure
how is Taurodontism identified in a patient?
radiographs
what is Taurodontism?
Enlargement of the body and pulp chamber of a multirooted tooth
in teeth with Taurodontism, there is an apical displacement of _________ and __________
pulpal floor and furcation
what causes Taurodontism?
Result of chromosomal alterations; associated with various syndromes
T/F: Hypercementosis can begin in childhood, and progresses throughout adulthood
FALSE
only found in adults
what condition has a strong association with Paget’s Disease of Bone
Hypercementosis
what is hypercementosis?
Asymptomatic deposition of excessive cementum
when/why should hypercemetosis be treated?
NO treatment necessary
only provides complications during extractions
_________ is defined as a curvature/bend of tooth roots
dilaceration
what is the etiology/cause of dilaceration?
trauma to developing tooth
why would dilacerated teeth cause treatment problems?
Extraction or RCT may be difficult
what is Amelogenesis Imperfecta?
Group of uncommon genetic disorders affecting enamel of teeth
why is Amelogenesis Imperfecta clinically important? What causes it?
Weak enamel is easily lost
Varied patterns of inheritance
T/F: Amelogenesis Imperfecta is only seen in adult dentition
False
seen in both primary and secondary
name the 3 divisions of Amelogensis Imperfecta
Hypoplastic
Hypomaturation
Hypocalcified
what are the clinical, and radiographic, signs of Amalogenesis imperfecta?
Clinical: rough, smooth, pitted, pigmented, or “snow-capped”
Radiographic: thin enamel of normal or decreased density; normal root and pulp morphology
_____________ is a dental abnormality with an Autosomal Dominant inheritance pattern
Dentinogenesis Imperfecta
what is the clinical appearance of dentinogenesis imperfecta?
Teeth appear translucent; “Opalescent teeth”
Enamel is normal, but poorly supported; rapid attrition of dentition is often seen
what are the radiographic findings for dentinogenesis imperfecta?
Bulbous crowns and obliteration of pulps
the findings of dentinogenesis imperfecta are similar to what other condition?
osteogenesis imperfecta
Dentinogenesis Imperfecta is due to mutation of the ________ gene
DSPP
the mutation of the DSPP gene causes a malformation of what protein?
“dentin sialophosphoprotein”
- one of the major non-collagenous proteins of dentin
what is the inheritance pattern of Dentin Dysplasia? how many types are there?
Autosomal dominant inheritance
2 types
what is type 1 dentin dysplasia?
Radicular Dentin Dysplasia
Radicular roots are very short “rootless teeth”, obliteration of pulp (crescent-shaped remnant in crown), periapical radiolucencies
what is type 2 dentin dysplasia?
Type II: Coronal Dentin Dysplasia
Enlarged pulps with “thistle tube” appearance, pulp stones
