📌 POINTS TO PONDER

• Fenestration is window-like circumscribed defect, whereas dehiscence is cleft-like split defect.
• Osteoblasts are bone builders, whereas osteoclasts are bone consumers.
• Matrix Gla protein is a negative regulator of mineralization.

📌 VIVA VOCE

Q1. Which is the least stable periodontal tissue?

Ans. Alveolar bone is the least stable periodontal tissue.

Q2. What is the distance between the crest of the alveolar bone and the cementoenamel junction in young adults?

Ans. It varies between 0.75 mm and 1.49 mm (average 1.08 mm).

Q3. Which cell produces RANKL?

Ans. RANKL is produced from the osteoblasts/stromal cells.

Q4. What is coupling?

Ans. It is interdependency of osteoblasts and osteoclasts in remodeling of the bone.

Q5. Why bone lining the socket is called as bundle bone?

Ans. Bone lining the socket is called as bundle bone as it provides attachment for periodontal ligament fiber bundles.

Q6. What is endosteum?

Ans. The tissue lining the internal bone cavities is called endosteum.

Q7. What is periosteum?

Ans. The outer aspect of cortical bone surrounded by a connective tissue membrane called as the periosteum.

Q8. What are fenestrations?

Ans. Fenestrations are the isolated areas in which root is denuded of bone and marginal bone is intact. 

Q9. What are dehiscences?

Ans. These are the denuded areas that extend through the marginal bone.

Q10. Which types of collagen are present in alveolar bone?

Ans. Type I (mainly), type III, V, XII and XIV.

📌 MULTIPLE CHOICE QUESTIONS (MCQs)

💡Coupling phenomenon is:

A. Association of osteoclast with bone surface forresorption

B. Association of osteoblast with the matrix for bonemineralization

C. Interdependency of osteoblasts and osteoclasts inremodeling

D. Contact between various osteocytes with inhaversian system for exchange of nutrients.

Answer : C

💡 The inactive osteoblasts are:

A. Osteocytes

B. Osteoclasts

C. Osteoproginator cells

D. Bone lining cells

Answer : D

💡 The enzyme closely associated with new bone formation is:

A. Acid phosphatase

B. Alkaline phosphatase

C. Succinic dehydrogenase

D. Both A and B

Answer : B

💡 Which of the following is bone gla protein?

A. Osteonectin

B. Bone sialoprotein

C. Osteocalcin

D. Osteopontin

Answer : C

💡 Following is true about osteoclast except:

A. Mononucleated cells

B. Having branching processes

C. Derived from circulating blood cells monocytes

D. Found in Howship’s lacunae.

Answer : A

💡 Function of osteoblast:

A. Bone formation by synthesizing organic matrixof bone

B. Cell-to-cell communication

C. Bone resorption

D. All of the above

Answer : D

💡 The term lamina dura refers to the radiographic image of the:

A. Periodontal ligament space

B. Alveolar bone proper

C. Cortical plates

D. Cancellous bone

E. Alveolar crest

Answer : B

💡 Following is true about fenestration and dehiscence except:

A. Fenestration is the isolated area in which root is denuded of bone and marginal bone is intact.

B. Dehiscence is the denuded area that extends through the marginal bone.

C. Dehiscence and fenestration are both associatedwith extreme buccal or lingual version of teeth

D. None of the above

Answer : D