Question 1

Impacted teeth cannot erupt because of:

Accepted Answer

Impacted teeth cannot erupt because they are blocked or obstructed by other teeth or bone structures. Lack of eruptive force, ankylosis, and bone pathology may affect the eruption process, but obstruction is the main reason for impacted teeth.

Question 2

The pseudocyst seen in this radiograph is surrounded by salivary gland tissue.  It is a(n) _____ bone cyst.

Accepted Answer

This radiograph shows a Stafne bone cyst, also known as a static bone cyst or lingual salivary gland depression. It is a rare, non-expansile, radiolucent lesion that is located in the posterior mandible and appears as a well-defined, corticated, round or ovoid radiolucency adjacent to the lingual surface of the mandible. It is caused by the lingual salivary gland, which compresses the bone during development, resulting in a concavity or depression in the mandible. As such, it is not actually a true cyst, but rather a developmental anomaly that is often asymptomatic and requires no treatment.

Question 3

Multiple supernumerary teeth may be a component of which of the following?

Accepted Answer

Multiple supernumerary teeth are a common feature of cleidocranial dysplasia, a genetic disorder affecting bone and tooth development. Dermoid cysts, syphilis, and static bone cysts are not typically associated with supernumerary teeth.

Question 4

Regional odontodysplasia is:

Accepted Answer

Regional odontodysplasia involves a decrease in radiodensity seen in one or more unerupted teeth in a quadrant. Regional odontodysplasia is not a genetic condition. Regional odontodysplasia is not caused by systemic illness. Regional odontodysplasia is more often seen in the anterior maxilla.

Question 5

Regional odontodysplasia is also referred to as:

Accepted Answer

Regional odontodysplasia is also known as ghost teeth because the teeth affected by this condition appear translucent or ghost-like on radiographs. Hypodontia is the absence of one or more teeth. Taurodontism is a condition in which the teeth have elongated pulp chambers and shortened root lengths. Supernumerary teeth are extra teeth that develop in addition to the normal number of teeth. None of these conditions are specific to regional odontodysplasia.

Question 6

Ingesting water with four times the amount of fluoride causes:

Accepted Answer

Ingesting water with four times the amount of fluoride causes brown-to-black staining. The amount of fluoride ingested does not cause cusp fractures. White spots on the middle third of smooth crowns are enamel hypocalcification. Teeth affected by fluorosis are generally decay resistant.

Question 7

The supernumerary tooth in this illustration is:

Accepted Answer

A supernumerary tooth that is located in the midline between the two central incisors is most likely a mesiodens. Mesiodens is the most common type of supernumerary tooth and usually results from the overgrowth of the dental lamina. Dilaceration is a curve or angle in the root or crown of the tooth, and it is not related to the presence of a supernumerary tooth. Twinning refers to the formation of two teeth from a single tooth bud, whereas gemination is the incomplete division of a single tooth bud, resulting in a large, double crown. These two conditions may result in supernumerary teeth, but they are not specific to mesiodens.

Question 8

Nonerupted supernumerary teeth should be extracted because of which of the following risks?

Accepted Answer

Nonerupted supernumerary teeth can cause the development of cysts around the crowns, which can lead to further complications such as infection and damage to the adjacent teeth. Therefore, extraction is necessary to prevent these risks. Malignant tumor development, internal resorption, and condensing osteitis are not directly associated with supernumerary teeth.

Question 9

Which one of the following defines a disturbance of the maturation of the enamel matrix?

Accepted Answer

Enamel hypocalcification is a disturbance of the maturation of the enamel matrix, leading to an insufficient amount of calcium in the enamel. This can result in white or yellow discoloration and increased susceptibility to dental caries. Turner tooth (A) is a term used to describe a tooth with a hypoplastic or underdeveloped enamel surface due to trauma or infection during tooth development. Mulberry molar (B) is a term used to describe a molars with multiple cusps, a characteristic of certain genetic conditions. Premature birth (C) can have an effect on tooth development, but it is not specifically related to disturbance of enamel matrix maturation.

Question 10

Enamel hypoplasia is the result of a disturbance of or damage to ameloblasts during enamel matrix formation. Which one of the following would not be a factor?

Accepted Answer

Shingles is a viral infection that does not directly affect ameloblasts or enamel formation. Genetics, ingestion of high concentrations of fluoride during tooth development, and vitamin deficiency during tooth development can all disrupt ameloblast function and lead to enamel hypoplasia.

Question 11

Pitting is the most common type of enamel hypoplasia seen in patients who have which condition during tooth development?

Accepted Answer

Febrile illnesses such as measles and chickenpox cause enamel hypoplasia showing pitting of the enamel. Drinking water with twice the recommended fluoride content causes white flecks or chalky areas of the enamel. Congenital syphilis causes mulberry molars and Hutchinson incisors. Herpes simplex is characterized by oral ulcers involving the soft tissues and not enamel hypoplasia.

Question 12

For which condition would pulp vitality be nonvital?

Accepted Answer

Pulp vitality is nonvital in the presence of a radicular cyst, as the necrotic pulp tissue can lead to the formation of a cyst. Median mandibular cyst, median palatal cyst, and periapical cemento-osseous dysplasia do not necessarily affect pulp vitality.

Question 13

Another name for dens invaginatus is:

Accepted Answer

Dens in dente is another name for dens invaginatus. Taurodontism is a developmental anomaly in which teeth exhibit elongated large pulp chambers and short roots. Dens evaginatus is a rare developmental anomaly in which an enamel cusp is found on the occlusal surface of mandibular premolars. Enamel pearl or enameloma is a projection of enamel found on the furcation area of maxillary molars.

Question 14

The developmental anomaly seen in this radiograph is:

Accepted Answer

The answer of The developmental anomaly seen in this radiograph...

Question 15

Which tooth is most commonly affected by dens in dente?

Accepted Answer

The maxillary lateral is the tooth most commonly affected by dens in dente. The maxillary central is not the most common tooth seen with dens in dente. The mandibular lateral is not the most common tooth seen with dens in dente. A supernumerary tooth is not seen with dens in dente.

Question 16

The projection of white material seen at the furcation area in this maxillary molar is a developmental anomaly.  You suspect:

Accepted Answer

The projection of white material seen at the furcation area is most likely an enamel pearl, which is a small, spherical enamel projection found in the furcation area of molars. Dens evaginatus typically presents as a tubercle or cusp on the occlusal surface, whereas a supernumerary cusp appears as an extra projection on the tooth surface. Calculus is a hard deposit of mineralized plaque that accumulates on teeth and is not a developmental anomaly.

Question 17

Dens in dente is a developmental anomaly often seen with:

Accepted Answer

Dens in dente is a developmental anomaly often seen with a periapical lesion. Dens evaginatus is an accessory occlusal cusp found on mandibular premolars. Tuberculated premolars occur when the mandibular premolars are affected with dens evaginatus. Dens in dente does not exhibit evidence of supernumerary roots.

Question 18

The pear-shaped radiolucency observed in this radiograph is most likely a _____ cyst.

Accepted Answer

The answer of The pear-shaped radiolucency observed in this radiograph...

Question 19

This radiograph clearly shows which developmental anomaly?

Accepted Answer

The radiograph shows a radiopaque structure within the coronal portion of the tooth, which is typical of dens in dente. Periapical pathology would appear as a radiolucency at the apex of the tooth. Caries would appear as a radiolucency within the tooth. Open contacts cannot be detected on a radiograph.

Question 20

The most common supernumerary tooth is called:

Accepted Answer

The most common supernumerary tooth is mesiodens, which is a small, cone-shaped tooth located in the midline of the upper or lower jaw, between the two central incisors. Distomolar and mulberry molar are not common supernumerary teeth, and Turner tooth is a term used for a tooth that has been affected by Turner syndrome, a genetic disorder.

Quiz 5: Developmental Disorders