Oral Path Quiz 6

What is another name for the nasopalatine duct cyst?

The incisive canal cyst.

What is the most common nonodontogenic cyst of the oral cavity?

The nasopalatine duct cyst.

What is a cyst of the incisive papilla?

A nasopalatine duct cyst localized to soft tissue within the incisive papilla.

What does a nasopalatine duct cyst look like radiographically?

A well-defined, heart-shaped radiolucency.

How is a nasopalatine duct cyst treated?

Surgical excision prior to prosthesis fabrication.

What does a median palatine cyst look like radiographically?

A well-defined, unilocular radiolucency in the midline of the hard palate.

How does a median palatine cyst relate to a nasopalatine duct cyst?

It's considered a more posterior form of a nasopalatine canal cyst.

How is a median palatine cyst treated?

Surgical enucleation.

What type of cyst is a nasolabial cyst?

A soft tissue cyst, with no alveolar bone involvement.

Where does a nasolabial cyst cause expansion?

The mucolabial fold in the maxillary canine area and the floor of the nose.

How is a nasolabial cyst treated?

Surgical excision.

What is another name for the lymphoepithelial cyst?

The branchial cleft cyst.

Where does the lymphoepithelial cyst occur?

Lateral neck, anterior to the sternocleidomastoid muscle.

How does a lymphoepithelial cyst form?

Epithelium becomes caught in a lymph node during development.

Where are intraoral lymphoepithelial cysts commonly found?

Floor of mouth, ventral tongue, and lateral border of the posterior tongue.

How is a lymphoepithelial cyst treated?

Surgical excision.

Where does an epidermal cyst occur?

A raised nodule in the skin of the face/neck.

What may an epidermal cyst originate from?

The epithelium of the hair follicle.

How is an epidermal cyst treated?

Surgical excision.

When does a dermoid cyst typically present?

At birth, or noted in young children.

Where is a dermoid cyst found if it occurs in the oral cavity?

The anterior floor of the mouth.

What can a dermoid cyst cause if it develops below the geniohyoid muscle?

A 'double chin' appearance.

What is a benign cystic teratoma?

Resembles dermoid cyst. It contains teeth, bone, muscle, and nerve in its wall.

How is a dermoid cyst treated?

Surgical excision.

How does a thyroglossal duct cyst form?

Forms along the tract the thyroid follows in development.

Where is a thyroglossal duct cyst usually located?

At or below the hyoid bone.

What is the classic clinical sign of a thyroglossal duct cyst?

Midline neck swelling that moves vertically when the patient swallows.

What does a thyroglossal duct cyst look like if located on the posterior tongue?

A smooth, firm mass.

How is a thyroglossal duct cyst treated?

Complete excision of the cyst, tract, and part of the hyoid bone.

What is the prognosis of a thyroglossal duct cyst?

Good, though malignant change has been known to occur.

What are globulomaxillary and median mandibular cysts now known to be?

Other odontogenic or nonodontogenic cysts/tumors.

What is another name for the Stafne defect?

A static bone cyst.

Is the Stafne defect a true cyst?

No, it's not a pathologic cavity.

Where is the Stafne defect usually found?

Posterior mandible, inferior to the mandibular canal.

Where else can a Stafne defect occur?

The anterior mandible or the ramus.

How is a Stafne defect treated?

Normally none; biopsy if radiolucency is above the mandibular canal.

What is another name for the simple bone cyst?

The traumatic bone cyst.

What does a simple bone cyst look like radiographically?

A well-defined, unilocular or multilocular radiolucency with scalloping around tooth roots.

Where is a simple bone cyst most common?

In the mandible.

What does surgery reveal in a simple bone cyst?

An empty cavity/void within the bone.

How is a simple bone cyst treated?

With curettage, after which it fills in with bone over about a year.

What is an aneurysmal bone cyst?

Blood-filled spaces surrounded by multinucleated giant cells and fibrous connective tissue.

What lesion does an aneurysmal bone cyst resemble?

A central giant cell granuloma.

What does an aneurysmal bone cyst look like radiographically?

A multilocular radiolucency with a 'honeycomb' or 'soap-bubble' appearance.

How is an aneurysmal bone cyst treated?

Surgical excision; excessive bleeding may occur.

What is anodontia?

Congenital absence of teeth.

What is total anodontia associated with?

Ectodermal dysplasia.

What is hypodontia?

Lack of one or more teeth (up to 5).

Which teeth are most commonly missing in hypodontia?

3rd molars, maxillary lateral incisors, and mandibular 2nd premolars.

What other factors can cause hypodontia?

Jaw lesions and radiation treatment.

What is oligodontia?

Missing 6 or more teeth, excluding 3rd molars.

How is hypodontia treated?

Prosthetic replacement to prevent drifting or tipping of teeth.

What are supernumerary teeth?

Extra teeth beyond the normal number.

What is typical of a supernumerary tooth's size?

Usually smaller than the normal tooth.

What is the most common supernumerary tooth?

A mesiodens, located between the central incisors.

What is the second most common supernumerary tooth?

Distodens, the maxillary 4th molar.

What is the difference between a natal tooth and a neonatal tooth?

Natal teeth are present at birth; neonatal teeth appear within the first month of life.

When is removal of a supernumerary tooth necessary?

If crowding, malpositioning, or noneruption of normal teeth occurs.

Why should a nonerupted supernumerary tooth be extracted?

Due to the risk of a cyst developing around its crown.

What syndromes are associated with multiple supernumerary teeth?

Cleidocranial dysplasia and Gardner's syndrome.

What is microdontia?

One or more teeth are smaller than normal.

What is true generalized microdontia associated with?

Down syndrome or pituitary dwarfism.

What is generalized relative microdontia?

Normal-sized teeth appear small in large jaws.

What is the most common form of microdontia?

Microdontia involving a single tooth, classically the peg-shaped maxillary lateral incisor.

How is microdontia treated?

Erupted microdonts are restored; impacted microdonts are removed.

What is macrodontia?

One or more teeth are larger than normal.

What is true generalized macrodontia associated with?

Rare. Pituitary gigantism.

What is the most common form of macrodontia?

Relative generalized macrodontia in people with normal or slightly larger teeth in small jaws.

How common is macrodontia affecting a single tooth?

Very uncommon.

What is gemination?

A single tooth germ attempts to divide, resulting in incomplete formation of two teeth.

Which teeth does gemination most commonly affect?

Anterior teeth, especially deciduous mandibular incisors.

What is the tooth count in gemination?

Tooth count is normal. One root.

How is gemination treated?

Alteration of the tooth to resemble a normal tooth.

What is fusion?

Union of two normally separate, adjacent tooth germs.

Which teeth does fusion most commonly affect?

Deciduous incisors, especially anterior maxillary incisors.

What is the tooth count in fusion?

One less than normal.

What is hypercementosis?

Excessive cementum on tooth roots. Frequently seen in Paget's disease.

What is concrescence?

Two adjacent teeth united by cementum only.

Where is concrescence most often seen?

Adjacent maxillary molars.

How is concrescence treated if extraction is needed?

Both fused teeth must be extracted together.

What is dilaceration?

An abnormal curve or angle in the root or crown of a tooth caused by trauma to the tooth germ during root development.

What precaution should be taken before treating a dilacerated tooth?

Obtain a preoperative radiograph if extraction or root canal treatment is needed.

What is an enamel pearl?

A small, spherical enamel projection on the root surface caused by abnormal displacement of ameloblasts during tooth formation.

What is the cause of enamel pearls?

Abnormal displacement of ameloblasts during tooth formation.

Where are enamel pearls usually found?

Maxillary molars, near root furcations or the CEJ; may be mistaken for calculus.

What is a talon cusp?

An accessory cusp in the cingulum area. Most common on the maxillary lateral incisor.

What syndrome is a talon cusp associated with?

Rubinstein-Taybi syndrome.

What is taurodontism?

Teeth with elongated, large pulp chambers and short roots, often described as 'bull-like' teeth.

What syndromes are associated with taurodontism?

Down syndrome, ectodermal dysplasia, Klinefelter syndrome, and hypophosphatasia.

What does taurodontism look like radiographically?

Shows a stretched appearance, enlarged pulp chamber, and short roots.

What is dens in dente also called?

Dens invaginatus, caused by the enamel organ invaginating into the tooth crown before mineralization.

Which tooth is most commonly affected by coronal dens in dente?

The maxillary lateral incisor.

What are the three types of coronal dens in dente?

Type I (invagination in crown only), Type II (extends below the CEJ), Type III (extends through the root out into apical third).

What does dens in dente look like radiographically?

A 'tooth within a tooth' appearance.

Which type of dens in dente is especially associated with periapical pathology?

Type II.

What is the treatment for dens in dente?

Tooth often non vital. Prophylactic restoration/endodontics/full coverage crowns.

What is dens evaginatus?

An accessory enamel cusp on the occlusal surface, most common on mandibular premolars.

What causes dens evaginatus?

Proliferation/outpouching of enamel epithelium during development.

What complication can occur with dens evaginatus?

Occlusal wear can cause pulpal exposure.

What are the causes of supernumerary roots?

External pressure, trauma, and metabolic dysfunction during tooth development.