NEET MDS Online Coaching Institute

SUBJECT: DENTAL ANATOMY

It is the first formed hard tissue. It is slightly harder than bone, softer than enamel
It is resilient and viscoelastic in nature and thus prevent s the fracture of the overlying enamel when occlusal forces are applied
It thus determines the shape of the crown and the number and size of the roots
Mature dentin comprises of 70% inorganic material, 20% organic material and 10% water by weight and 45%, 33% and 22% respectively by volume.
It is laid down by the process of dentinogenesis which is a cyclic and rhythmic even

Primary Physiological Dentin- it forms most of the dentine that outlines the pulp chamber
Mantle Dentin
Circumpulpal Dentin
Secondary Physiological Dentin- it develops after root formation is completed and continues to be deposited slowly throughout the life of the tooth
Tertiary Dentin- it is deposited as a protective response to physical, chemical or microbial insults to the tooth

1. Which is the tissue that affords resilience to the tooth structure

a) Cementum
b) Enamel
c) Dentin
d) None of the above

2. Which is the first formed dentin

a) Mantle dentin
b) Circumpulpal dentin
c) Predentin
d) None of the above

3. Dentin is derived from

a) Tooth bud
b) Dental papilla
c) Dental sac
d) None of the above

1 - (C)
2 - (A)
3 - (B)