Biology

Dental and Oral Biology

924 Questions

Dental and Oral Biology focuses on the structure, development, and function of teeth and oral tissues. It covers key concepts like dental formulas, tooth eruption, and common oral diseases. These topics are essential for medical and biology entrance examinations.

Dental formulaTooth anatomyMilk teethOral diseasesTooth decay

Dental and Oral Biology Questions

Multiple choice

Cracked tooth syndrome can be effectively diagnosed by

  1. radiological examination

  2. subjective symptoms or horizontal percussion

  3. electric pulp testing

  4. thermal pulp testing

  5. palpation and vertical percussions
Reveal answer Fill a bubble to check yourself
B Correct answer
Explanation

Cracked tooth syndrome can be effectively diagnosed by subjective symptoms or horizontal percussion.

Multiple choice

Which of the following statements is false about pulpitis?

  1. Irreversible pulpitis may be asymptomatic.

  2. In irreversible pulpitis, there is abnormal response to cold and more current is required in electric testing in advanced stages.

  3. Pulp polyp is less sensitive than pulp and more current is required.

  4. In reversible pulpitis, more response to cold and more current is required to elicit a response.

  5. All of the above
Reveal answer Fill a bubble to check yourself
D Correct answer
Explanation

This is an incorrect statement about pulpitis.

Multiple choice

Which of the following statements is/are false about internal resorption?

  1. Internal resorption is an idiopathic slow or fast progressive resorptive process occurring in the dentin of the pulp chamber or root canals of teeth.

  2. Internal resorption is the result of osteoclastic activity.

  3. Internal resorption in the root of a tooth is symptomatic.

  4. Only 1, 2 and 3

  5. Internal resorption in the root of tooth is asymptomatic.
Reveal answer Fill a bubble to check yourself
C Correct answer
Explanation

This is an incorrect statement about internal resorption because internal resorption in the root of tooth is asymptomatic. So, it is the correct answer.

Multiple choice

Which of the following statements is/are false about pulp polyp?

  1. Pulp polyp is a productive pulpal inflammation due to an extensive carious exposure of a young pulp.

  2. The surface of the pulp polyp is usually covered by stratified squamous epithelium.

  3. Both (1) and (2)

  4. The surface of the pulp polyp is usually covered by stratified columnar epithelium.

  5. Pulp polyp is generally seen only in the teeth of children and young adults.
Reveal answer Fill a bubble to check yourself
D Correct answer
Explanation

This is an incorrect statement about pulp polyp because the surface of the pulp polyp is usually covered by stratified squamous epithelium.

Multiple choice

In the mouth of rabbit, diastema is a gap between:

  1. premolar and molar

  2. canine and incisor

  3. canine and premolar

  4. incisor and premolar
Reveal answer Fill a bubble to check yourself
D Correct answer
Explanation

In rabbits, the diastema is the natural gap between the incisors and premolars. This space allows the manipulation of food during chewing and is characteristic of many herbivorous mammals. The other tooth pairs listed are adjacent without significant gaps.

Multiple choice

Which of the following bones constitute the lower jaw in mammal?

  1. Squamosal

  2. Dentary

  3. Quardrate

  4. Maxilla
Reveal answer Fill a bubble to check yourself
B Correct answer
Explanation

In mammals, the lower jaw consists of a single bone called the dentary. This is a key mammalian characteristic distinguishing them from other vertebrates, where the lower jaw comprises multiple bones (quadrate, articular, etc.).

Multiple choice

The teeth of shark are modified:

  1. ectoderm

  2. keratin substance

  3. placoid scales

  4. dermis
Reveal answer Fill a bubble to check yourself
C Correct answer
Explanation

Shark teeth are evolutionarily modified placoid scales, also called dermal denticles, which cover the shark's skin. These structures have the same basic composition as teeth - an enamel-like outer layer and a dentine core surrounding a pulp cavity. As teeth wear out or are lost, new ones rotate forward from reserve rows behind.

Multiple choice

Which of the following is not true regarding flourosis?

  1. Flourosis is the most common cause of dental caries in children.

  2. Deposition of flurides in the skeletal system and muscles.

  3. Deflouridation is done by Nalgonda technique.

  4. Genu valgum
Reveal answer Fill a bubble to check yourself
A Correct answer
Explanation

Option A claims 'Fluorosis is the most common cause of dental caries in children' - this is the statement that is NOT true. Fluorosis causes enamel defects and mottling, NOT caries. Dental caries is caused by acid-producing bacteria (Streptococcus mutans) fermenting sugars. Options B, C, and D ARE true manifestations of fluorosis.

Multiple choice

A 3-year old girl is posted for tonsillectomy. On examination it is found that she has a midline cystic swelling extending till below the hyoid bone. It is painless and moves with deglutition. The thyroid examination is normal. What should be done next?

  1. Percutaneous aspiration

  2. I.V. antibiotics

  3. Surgical removal

  4. Observation
Reveal answer Fill a bubble to check yourself
C Correct answer
Explanation

This clinical presentation (midline neck cyst that moves with deglutition, extending below hyoid, normal thyroid gland) is classic for a thyroglossal duct cyst. These are embryologic remnants that can present in childhood. Surgical removal is the definitive treatment (Sistrunk procedure) to prevent recurrence and infection. Aspiration would lead to recurrence, and observation is inappropriate given the risk of complications. IV antibiotics are not indicated for an uncomplicated cyst.

Multiple choice

Pulp cavity of teeth is lined by

  1. odontoblast

  2. chondroblast

  3. osteoblast

  4. amyloblast

  5. None of these
Reveal answer Fill a bubble to check yourself
A Correct answer
Explanation

An odontoblast is a cell of neural crest origin i.e. part of the outer surface of the dental pulp, and whose biological function is dentinogenesis, which is the formation of dentin, the substance beneath the tooth enamel on the crown and the cementum on the root.