Question 1

All the following are correct relative to amelogenesis imperfecta except:&#10;A)Caused by environmental factors&#10;B)Affects all teeth&#10;C)Usually treated for cosmetic purposes&#10;D)Pulp chambers are unaffected&#10;E)Dentin is unaffected

Accepted Answer

Amelogenesis imperfecta is a genetic disorder that affects the formation of tooth enamel. It is not caused by environmental factors. B is correct as it affects all teeth. C is partially correct as treatment may be done for both cosmetic and functional purposes. D is incorrect as the pulp chambers may be affected. E is incorrect as dentin may also be affected in some types of amelogenesis imperfecta.

Question 2

The phenomenon of fusion of cementum of two or more teeth is known as:&#10;A)Fusion&#10;B)Concrescence&#10;C)Taurodontism&#10;D)Ankylosis&#10;E)None of the above

Accepted Answer

The phenomenon of fusion of cementum of two or more teeth is known as concrescence. Ankylosis is the pathological fusion of tooth root with the surrounding bone, while taurodontism is a developmental anomaly characterized by elongation of pulp chambers and shortening of roots. Choice A (Fusion) is a broad term and could refer to various anatomical structures or processes.

Question 3

Periapical lesions (cysts and granulomas) are found in a patient with teeth that show nearly obliterated pulps and short spiky roots. Teeth exhibit normal clinical color. This patient probably has:&#10;A)Dentin dysplasia&#10;B)Dentinogenesis imperfecta&#10;C)Amelogenesis imperfecta&#10;D)Regional odontodysplasia&#10;E)Fluorosis

Accepted Answer

Dentin dysplasia is characterized by root anomalies such as short, spiky roots, and periapical lesions like cysts and granulomas, despite the teeth appearing clinically normal in color.

Question 4

The dental phenomenon in which teeth show elongated crowns and pulp chambers are enlarged in apical-occlusal height is known as:&#10;A)Supernumerary teeth&#10;B)Regional odontodysplasia&#10;C)Taurodontism&#10;D)Dens evaginatus&#10;E)Dens invaginatus

Accepted Answer

Taurodontism is a dental anomaly where the teeth show elongated crowns and the pulp chambers are enlarged in apical-occlusal height. It is particularly common in molars, where the occlusal part is higher than normal, and the roots are shorter. The name comes from the Latin word "taurus" meaning "bull" due to the perceived similarity to a bull's teeth. Supernumerary teeth refer to the presence of extra teeth, regional odontodysplasia is a genetic condition that affects the development of teeth, Dens evaginatus is an accessory cusp on the occlusal surface of a tooth, and Dens invaginatus is a deep surface invagination into a tooth. None of these conditions present with the elongation of the teeth and enlarged pulp chambers seen in taurodontism.

Question 5

Enamel hypoplasia can result from which of the following?&#10;A)Congenital syphilis&#10;B)Nutritional deficiencies in utero or in childhood&#10;C)Exanthematous diseases of childhood such as varicella&#10;D)Fluoride in drinking water at levels greater than 1 ppm&#10;E)All the above

Accepted Answer

Enamel hypoplasia can result from all of the listed factors. Congenital syphilis and nutritional deficiencies in utero or in childhood can affect tooth development, leading to enamel defects. Exanthematous diseases such as varicella can also cause enamel hypoplasia by disturbing tooth formation during the active phase of the disease. Fluoride in drinking water at levels greater than 1 ppm can lead to enamel fluorosis, which is a type of enamel hypoplasia with white spots or streaks on the teeth.

Question 6

Congenital anodontia (partial or complete) is a feature of which of the following?&#10;A)Hereditary ectodermal dysplasia&#10;B)Dentin dysplasia&#10;C)Gardner's syndrome&#10;D)Cleidocranial dysplasia (dysostosis)&#10;E)None of the above

Accepted Answer

Congenital anodontia (partial or complete absence of teeth) is a characteristic feature of hereditary ectodermal dysplasia, a group of genetic disorders affecting the development of hair, teeth, nails, sweat glands, and other ectodermal structures. Dentin dysplasia, Gardner's syndrome, and cleidocranial dysplasia are not typically associated with congenital anodontia.

Question 7

The phenomenon of a single tooth germ attempting to make two teeth is known as:&#10;A)Concrescence&#10;B)Fusion&#10;C)Gemination&#10;D)Ankylosis&#10;E)None of the above

Accepted Answer

The phenomenon of a single tooth germ attempting to make two teeth is known as gemination. Concrescence refers to the fusion of two adjacent teeth due to deposition of hard tissue after root formation. Fusion refers to the union of two adjacent tooth germs at an early stage of development. Ankylosis is the fusion of the tooth root to the surrounding bone.

Question 8

A 16-year-old boy presents with yellow, severely abraded teeth (entire dentition). Radiographs show teeth with opacified pulps and short roots. The patient has no pain, and no periapical lesions are present. This patient has which of the following?

A)Dentin dysplasia
B)Dentinogenesis imperfecta
C)Amelogenesis imperfecta
D)Taurodontism
E)Regional odontodysplasia

Accepted Answer

The patient's presentation of yellow, severely abraded teeth with opacified pulps and short roots is characteristic of dentinogenesis imperfecta. Other features of this genetic condition may include brittle bones and blue sclerae.

Question 9

A 7-year-old patient presents with a quadrant of teeth showing abnormal formation of both enamel and dentin. All his other teeth appear clinically normal. Radiographically, the affected teeth can be described as "ghost teeth." He has:

A)Regional odontodysplasia
B)Dens evaginatus
C)Dentin dysplasia
D)Ectodermal dysplasia
E)Cleidocranial dysplasia

Accepted Answer

Regional odontodysplasia is a rare disorder that affects teeth in a specific area or quadrant of the mouth, causing abnormal enamel and dentin formation. The radiographic appearance of the affected teeth is often described as "ghost teeth." The other options listed do not typically present with such localized findings.

Question 10

Aplasia of secondary skin structures, partial anodontia, and xerostomia are features of:&#10;A)Cleidocranial dysplasia&#10;B)Ectodermal dysplasia&#10;C)Amelogenesis imperfecta&#10;D)Nevoid basal cell carcinoma syndrome&#10;E)Osteogenesis imperfecta

Accepted Answer

Aplasia (underdevelopment) of secondary skin structures such as hair, nails, and sweat glands, partial anodontia (missing teeth), and xerostomia (dry mouth) are classic features of ectodermal dysplasia. Cleidocranial dysplasia is a skeletal disorder characterized by skull and collarbone abnormalities, while amelogenesis imperfecta is a hereditary disorder affecting tooth enamel. Nevoid basal cell carcinoma syndrome is a genetic condition predisposing individuals to skin cancer, and osteogenesis imperfecta is a disorder causing brittle bones.

Question 11

Poorly formed &#34;shells&#34; of teeth are seen in which of the following?&#10;A)Dentin dysplasia&#10;B)Hypophosphatasia&#10;C)Regional odontodysplasia&#10;D)Cleidocranial dysplasia&#10;E)None of the above

Accepted Answer

The answer of Poorly formed &#34;shells&#34; of teeth are seen...

Question 12

The mesiodens:&#10;A)Probably occurs as a result of continued proliferation of the dental lamina&#10;B)Is the most common supernumerary tooth&#10;C)Most commonly occurs in the midline of the maxilla&#10;D)May also be a microdont&#10;E)All the above

Accepted Answer

The answer of The mesiodens:&#10;A)Probably occurs as a result of...

Question 13

Two brothers present with yellow teeth (entire dentition) and diastemas. Radiographically, dentin appears normal. Their father has a similar condition. This is most likely which of the following?&#10;A)Amelogenesis imperfecta&#10;B)Dentinogenesis imperfecta&#10;C)Environmental hypoplasia&#10;D)Fluorosis&#10;E)Regional odontodysplasia

Accepted Answer

The answer of Two brothers present with yellow teeth (entire...

Question 14

Premature deciduous tooth loss may occur in association with all the following except:&#10;A)Amelogenesis imperfecta&#10;B)Hyperthyroidism&#10;C)Burkitt's lymphoma&#10;D)Langerhans cell disease

Accepted Answer

The answer of Premature deciduous tooth loss may occur in...

Question 15

Tooth extraction is made more difficult by all the following except:&#10;A)Paget's disease&#10;B)Pulp stones&#10;C)Dilaceration&#10;D)Concrescence&#10;E)Albers-Schonberg disease

Accepted Answer

The answer of Tooth extraction is made more difficult by...

Question 16

Dens invaginatus:&#10;A)Probably occurs as a result of continued proliferation of the dental lamina&#10;B)Is a common lesion of third molars&#10;C)Is always a supernumerary tooth&#10;D)Cannot be detected radiographically&#10;E)None of the above

Accepted Answer

The answer of Dens invaginatus:&#10;A)Probably occurs as a result of...

Question 17

Which of the following is typically associated with pulpitis and periapical inflammation following wear of a supernumerary cusp?&#10;A)Amelogenesis imperfecta&#10;B)Regional odontodysplasia&#10;C)Turner's tooth&#10;D)Dens evaginatus&#10;E)Dens invaginatus

Accepted Answer

The answer of Which of the following is typically associated...

Question 18

Serum calcium would be significantly elevated in which of the following?&#10;A)Central giant cell granuloma&#10;B)Cherubism&#10;C)Ameloblastoma&#10;D)Langerhans cell disease (idiopathic histiocytosis) of the mandible&#10;E)None of the above

Accepted Answer

The answer of Serum calcium would be significantly elevated in...

Deck 16: Abnormalities of Teeth