A cyst formed when the stellate reticulum degenerates:

 # A cyst formed when the stellate reticulum degenerates: 

a. Eruption cyst 

b. Dentigerous cyst 

c. Keratocyst 

d. Radicular cyst 

The correct answer is A. Eruption cyst.

An eruption cyst is a type of dentigerous cyst formed when the stellate reticulum degenerates, leaving a cavity lined by the outer enamel epithelium before or during tooth eruption.

Eruption cyst is defined as an odontogenic cyst with the histologic features of a dentigerous cyst that surrounds a tooth crown that has erupted through bone but not soft tissue and is clinically visible as a soft fluctuant mass on the alveolar ridges.

An eruption cyst or ‘eruption hematoma’ is in fact a dentigerous cyst occurring in the soft tissues (Shear, 1992). Whereas the dentigerous cyst develops around the crown of an unerupted tooth lying in the bone, the eruption cyst occurs when a tooth is impeded in its eruption within the soft tissue overlying the bone.

60-74 micrometer sized particles contained in:

 # 60-74 micrometer sized particles contained in: 

A. Coarse grit diamond bur 

B. Medium grit diamond bur 

C. Fine grit diamond bur 

D. Very fine grit diamond bur 

The correct answer is C. Fine grit diamond bur.

The particle sizes of coarse, medium, fine and very fine grit diamond burs are 125-150 micrometer, 88-125 micrometer, 60-74 micrometer and 38-44 micrometer respectively. 

The width of keratinized gingiva is measured as the distance from the:

 # The width of keratinized gingiva is measured as the distance from the: 

A. Free gingival margin to the mucogingival junction 

B. Cementoenamel junction to the mucogingival junction 

C. Free gingival groove to the mucogingival junction 

D. Free gingival margin to the base of the pocket 

The correct answer is A. Free gingival margin to the mucogingival junction.

Keratinized gingiva extends from the free gingival margin to the mucogingival junction. The attached gingiva extendsfrom the free gingival groove to the mucogingival junction. 

What is a second-order bend in orthodontic wire?

# What is a second-order bend in orthodontic wire? 

A. Bend to position a tooth buccolingually 

B. Bend to provide angulation of a tooth in mesiodistal direction (tip) 

C. Bend to provide correct angulation of a tooth in labiolingual direction (torque) 

D. Bend to rotate a tooth 

The correct answer is B. Bend to provide angulation of a tooth in mesiodistal direction (tip) 

A second-order bend is placed to provide angula tion of a tooth in the mesiodistal direction, also called “tip.” A first-order bend is placed in an arch wire to position a tooth in the labiolingual direc tion (in-out bend) or to rotate a tooth as seen in the occlusal plane. A bend to provide angulation in the labiolingual direction is called a third-order bend (torquing bend).