Ch 2 - Abnormalities of Teeth 3 Flashcards
Defined as an attempt of a single tooth bud to divide
gemination
The union of two normally separated tooth buds with the resultant formation of a joined tooth with confluence of dentin
fusion
The union of two teeth by cementum without confluence of the dentin
concresence
People argue that gemination, fusion, and concresence should be discontinued and replaced with this term:
twinning (lol)
A single enlarged tooth or joined (i.e., double)
tooth in which the tooth count is normal when the anomalous tooth is counted as one
Gemination
A single enlarged tooth or joined (i.e., double) tooth in which the tooth count reveals a missing tooth when the anomalous tooth is counted as one.
Fusion
Which population has a higher prevalance of “double teeth” (fusion/gemination) compared to whites?
Asian
Gemination is more common in the ______ arch , whereas
fusion tends to occur more frequently in the ______ arch.
gemination = maxilla….fusion = mandible
Accessory cusp located on the palatal surface of the mesiolingual cusp of a maxillary molar…Prevelence in whites? asians?
cusp of Carabelli..90% whites, rare in Asians
Accessory cusp on the mesiobuccal cusp of a mandibular permanent or deciduous molar
protostylid
A well-delineated additional cusp that is located on the surface of an anterior tooth and extends at least half the distance from the CEJ to the incisal edge
talon cusp
Most common tooth for a talon cusp
permanent maxillary lateral incisor
4 ethnicities for talon cusp
- Asian 2.Native Americans 3. Inuit 4. Arab descent
6 disorders associated with a talon cusp (so freaking random)…which one has the strongest correlation?
- Rubinstein-Taybi syn(strongest: 92%) 2. Mohr syn 3. Ellis-van Creveld syn 4. incontinentia pigmenti achromians 5. Berardinelli-Seip syn 6. Sturge-Weber angiomatosis
A cusplike elevation of enamel located in the central groove or lingual ridge of the buccal cusp of premolar or molar teeth
Dens evaginatus
What is a Leong premolar?
an alternate term for dens envaginatus
Which arch has a marked predominance for dens evaginatus?
mandibular
4 ethnicities for dens evaginatus
1-4 % prev 1. Asians 2. Inuit 3. Native Americans 4. rare in whites
Dens evaginatus is seen in association with what other tooth variation?
shovel-shaped incisors
Shovel-shaped incisors occur predominantly in Asians,
with a prevalence of approximately 15% in whites but close to 100% in what 2 groups?
Native Americans and the Inuit
What is the alternate term for Dens Invaginatus?
dens in dente
Which tooth is most commonly affected by dens invaginatus?
perm max lat incisors
What is the term for a dens invaginatus that disturbed the formation of the tooth?
dilated odontome
_______ dens invaginatus is rare and thought to arise
secondary to a proliferation of Hertwig root sheath, with the formation of a strip of enamel that extends along the surface of the root.
Radicular
What is the most common tooth affected by enamel pearls?
maxillary permanent molars
What is the % range for prevelence of enamel pearls? Which ethnicity is most affected?
1.1-9.7%….Asians
Which tooth is affected most by cervical enamel extensions?
mandibular molars
Cervical enamel extensions: What 4 regions have found a high prevelence? (20% - 78%)
- US (lower 48) 2. Japan 3. China 4. Alaska
Even though the association is controversial, cervical enamel extensions can cause an inflammatory cyst at the buccal furcation of a molar and are thus called _______
buccal bifurcation cysts
Term for an enlargement of the body and pulp
chamber of a multirooted tooth, with apical displacement of the pulpal floor and bifurcation of the roots
Taurodontism
An increased frequency of taurodontism has been reported in patients with what 3 maxillofacial disorders? (think general)
hypodontia, cleft lip, and cleft palate
Please give 5 (of 20) syndromes associated with taurodontism
- Amelogenesis imperfecta (IE, IV) 2. Down syn 3. Ectodermal dysplasia 4.Kleinfelter syn 5. Oral-facial-digital type II
A nonneoplastic deposition of excessive cementum that is continuous with the normal radicular cementum.. (2 terms plz)
Hypercementosis (cemental hyperplasia)
What 4 things help distinguish a cementoblastoma from hypercementosis?
- pain 2. cortical expansion 3. continued enlargment 4. age - Blastoma = kids, cementosis = adults
Which tooth is most affected by hypercementosis?
mand molars
8 systemic factors associated with hypercementosis (all are weak associations except for which one?)
- Acromegaly/gigantism
- Arthritis
- Calcinosis
- Paget disease(strongest association)
- Rheumatic fever
- Thyroid goiter
- Gardner syndrome
- Vitamin A deficiency
What is the leading cause of dilaceration? What age does this typically occur by? What is the most common tooth affected?
trauma by 4 years of age…mand 3rd molars
4 syndromes associated with dilaceration
- Smith-Magenis syn 2. Ehlers-Danlos 3.Axenfeld-Reiger syn 4. congenital ichthyosis (dry, scaly, thickened skin)
What is the most common tooth affected by supernumerary roots?
permanent 3rd molars (max or mand)
What are the 2 primary diagnostic features of Otodental syndrome? What are 3 less often associated findings?
- sensorineural hearling loss 2. globodontia….less associated 1. ocular coloboma 2. odontomas 3. numerous microdontic teeth
Inheritance pattern, chromosome, and gene mutation for otodental syndrome?
AD….11q13….haploinsufficiency of FGF3
Which teeth are affected by globodontia?
primary and permanent cuspids and molars
What is the most excellent description of the occlusal surface of a molar globodontic tooth?
“tied end of a sausage” lol
What are the 4 syndromes associated with colobomas?
- Regional odontodysplasia 2.otodental syndrome 3. Gorlin syndrome 4. Mandibulofacial dysostosis (Treacher Collins)
A rare hereditary dental anomaly in which numerous teeth resemble those noted in carnivores…what is the inheritance pattern?
Lobodontia…AD
Which teeth are most commonly affected by lobodontia? What is the descriptive term used?
cuspids and premolars, “fang-like” cusps
What encompasses a complicated group of conditions that demonstrate developmental alterations in the structure of the enamel in the absence of a systemic disorder or syndrome?
Amelogenesis Imperfecta
What is the name of the classification system for Amelogenesis Imperfecta?
Witkop (Same Witkop as Witkop-Von Sallmann Syndrome aka HBID)
What are the 8 associated gene mutations (and their protein products) with Amelogenesis Imperfecta?
- AMELX (amelogenin protein, X-linked, 14 mutations known)
- ENAM (enamelin protein, AD and AR)
- MMP-20 (enamelysin protease, AR)
- KLK4 (kallikren-4 protease)
- FAM83H (AD, highest prevelance and most severe enamel alterations)
- WDR72 (scaffold for protein-protein interactions, AR)
- C4orf26 (extracellular matrix protein in the enamel organ, AR, Omani family)
- DLX3 (controversial involvment, assoc w taurodontism)
What is the prevelence of Amelogenesis imperfecta in the US?
1:14,000 (so approx 24,000 people in the US)….compared to 1:700 in Sweden! woah! (14,000 people)
The X-linked patterns of generalized thin amelogenesis imperfecta are a lesson in what genetic effect?
lyonization
hypocalcification pattern of Amelogenesis Imperfecta has been associated with “_______” enamel
“cheesy” enamel
In a person with _________ amelogenesis imperfecta, the affected teeth are normal in shape but exhibit white opaque enamel that may reveal areas of mottling. Can resemble dental fluorosis
hypomaturation
In the ________ _______ Amelogenesis Imperfecta pattern, the surface enamel is mottled and agar-brown. The enamel often fractures from the underlying dentin and is soft enough to be punctured by a dental explorer.
pigmented hypomaturation
Which shows lyonization more: X-linked hypomaturation of AI or X-linked hypoplastic AI?
lyonization is not as obvious in hypomaturation as that seen in the X-linked hypoplastic pattern.
______ _____ AI patterns exhibit a zone of white opaque enamel on the incisal or occlusal one quarter to one-third of the crown
snow-capped hypomaturation
Name that AI pattern: “denture dipped in white paint”
Snow-capped hypomaturation
_________ amelogenesis imperfecta, the teeth are appropriately shaped on eruption, but the enamel is very soft and easily lost.
hypocalcified
What are the 4 clinical categories for Amelogenesis Imperfecta?
- Hypoplastic
- Hypomaturation
- Hypocalcification
- AI with Taurodontism (Hypomaturation-Hypoplastic)
What syndrome has a pattern of teeth alteration similar to amelogenesis imperfecta with taurodontism?
.
tricho-dento-osseous syndrome
What are the 4 features of tricho-dento-osseous syndrome?
- Pattern of teeth alteration similar to AI with taurodontism
- kinky hair
- osteosclerosis
- brittle nails
Which form of Amelogenesis Imperfecta is associated with nephrocalcinosis and sometimes renal failure?
generalized thin hypoplastic amelogenesis
imperfecta
Name that clincal AI type: pinpoint-to-pinhead–sized pits are scattered across the surface of the teeth and do not correlate with a pattern of environmental damage
generalized pattern of hypoplastic AI
Name that AI type: the affected teeth demonstrate
horizontal rows of pits, a linear depression, or one large area of hypoplastic enamel. Typically, the altered area is located in the middle third of the buccal surfaces of the teeth.
localized pattern of hypoplastic AI
Name that AI type: the enamel is extremely
thin with teeth that are shaped like crown preparations and demonstrate open contact points.
generalized thin variant of hypoplastic AI
Name that AI type: the affected teeth are normal in shape but exhibit white opaque enamel that may reveal areas of mottling.
hypomaturation AI
