1. Development of tooth begins at __________ week of IU life

A. 6 weeks
B. 4 weeks
C. 3 weeks
D. 2 weeks

Answer- A
It starts in the 37th day of IU life with the formation of the primary epithelial band, which grows into the ectomesenchyme to give rise to the future tooth buds.

2. The ectomesenchymal cells and fibers that surround the enamel organ and dental papillae are

A. Alveolar bone
B. Dental follicle
C. Dental sac
D. None of the above

Answer- B and C
Dental Sac or Dental follicle are ectomesenchymal cells and fibers which gives rise to cementoblasts, osteo blasts and fibroblasts.
Dental Sac and Dental follicle are used as synonyms

3. 80% of the nerve fibers in the pulp tissue are

A. A delta
B. A alpha
C. A beta
D. C fibers

Answer- D
Majority of the nerve fibers entering the pulp are unmyelinated. This corresponds to the C fibers.

4. Un-mineralized zone of dentin seen above the odontoblastic zone are

A. Intertubular dentin
B. Peritubular dentin
C. Predentin
D. Interglobular dentin

Answer- C
Predentin is a precursor to the mature mineralized secondary dentin. It is found just above the odontoblastic cell layer.

5. In molars with radix paramolaris extra root is seen

A) Lingually
B) Mesially
C) Distally
D) Buccally

Ans : D
Mandibular molars can have an additional root located lingually (the radix entomolaris) or buccally (the radix paramolaris)

6. First recognizable zone of enamel caries

A) Body of the lesion
B) Dark zone
C) Translucent zone
D) Surface zone

Answer : C
Translucent Zone

7. What should not be used to sterilize dental handpiece?

A) Chemiclave
B) Autoclave
C) Dry heat
D) Ethylene oxide

Answer -C
Dry heat damages the linings and cartridges.

8. Which is not a feature of exploratory instrument

A) Large diameter
B) Small Diameter
C) Light weight
D) None Answer

Answer : A

Exploratory instrument should be light weight which gives better tactile sensation. The diameter should be as small which helps to find out incipient demineralised lesions

9. Cavosurface margin on the occlusal surface of composite is

A) 80 degree
B) 90 degree
C) 120 degree
D) 160 degree

Ans: B
Occlusal surface preparation for composite result in minimal unsupported enamel. 90 degree margins are preferred.

10. ISO Technical committee (TC) number for dentistry

A)104
B) 105
C) 106
D) 107

Answer C) 106

International Organization for Standardization’, ISO is an independent, non-governmental international organization. ISO/TC 106 contributes to the quality and safety of products used in the treatments by dental professionals as well as hygiene products used by the public.