SEARCH:

The advantage of metal base denture is:

 # The advantage of metal base denture is:
A. Increase in tissue tolerance
B. Easy laboratory procedure
C. Rebasing and relining are quite easy
D. Increase in restorative cost



The correct answer is A. Increase in tissue tolerance.

Advantages of metal denture base
  1. Mandibular dentures are heavier. So the retention and stability are improved.
  2. Improved thermal conductivity gives good sensory interpretation.
  3. They are strong even in thin sections. Thin sections are very comfortable for the patient.
  4. Easier to maintain.

Indirect retainers of partial denture:

 # Indirect retainers of partial denture:
A. Engages undercut areas
B. Most effective when close to direct retainer
C. Must be constructed with flexible materials like plastics
D. Should resist rotatory forces about fulcrum



The correct answer is D. Should resist rotatory forces about fulcrum.

When the distal extension denture base is dislodged from its basal seat, it tends to rotate around the fulcrum lines. Theoretically, this movement away from the tissues can be resisted by activation of the direct retainer, the stabilizing components of the clasp assembly, and the rigid components of the partial denture framework, which are located on definite rests on the opposite side of the fulcrum line away from the distal extension base. These components are referred to as indirect retainers. Indirect retainer
components should be placed as far as possible from the distal extension base, which provides the best leverage advantage against dislodgment. 

The midline fracture of the maxillary denture are mainly due to:

 # The midline fracture of the maxillary denture are mainly due to:
A. Teeth set too buccally
B. No midline relief
C. Ridge resorption
D. All of the above



The correct answer is D. All of the above.

Several factors have been attributed to be the cause of midline fracture i.e. flexural fatigue resulting from cyclic deformation and factors that exacerbate the deformation of the base or alter its stress distribution may predispose the denture to fracture. Other factors which form areas of stress concentration such as a large frenal notch, dentures with thin or underextended flanges, poorly fitting dentures or a lack of adequate relief, dentures with a wedged or locked occlusion have been implicated. Poor clinical design, dentures which have been previously repaired, poor laboratory technique, use of porcelain teeth, increase in stress concentration at the tooth/denture base interface, heavy or uneven masticatory forces, unbalanced occlusion, patient related habits, diastema and maxillary tori are other common causes for midline fractures of upper dentures.

Cavosurface margin angulation in chamfer finish line is:

 # Cavosurface margin angulation in chamfer finish line is:
A. Always 90 degree
B. 90 degree or less than 90 degree
C. 90 degree or more than 90 degree
D. 120 degree


The correct answer is C. 90 degree or more than 90 degree.

Chamfer is an obtuse-angled finish line. Indicated where metal forms the margin of a restoration, e.g. complete metal crown. Should not be given for porcelain restorations as the obtuse angle produces shearing forces which is not well tolerated by porcelain. It is prepared using a round-end tapering diamond. This is produced by sinking in half the diamond into the tooth. The tip produces the chamfer while the sides give the necessary taper to the axial surface. 

Cavosurface angle of less than 90 degree produces a lip of unsupported enamel which fractures easily.



MCQs on Pathology of Blood Cells - General Pathology MCQs


# Which of the following is a nutritional deficiency anemia?
A. Aplastic anemia
B. Sickle cell anemia
C. Spherocytosis
D. Megaloblastic anemia

# Megaloblastic anemia is related to:
A. Folic acid and Vit. 12 deficiency
B. Iron deficiency
C. Vit. C deficiency
D. Vit. K deficiency

A prepared cavity is best protected from moisture by:

 # A prepared cavity is best protected from moisture by:
A. Cotton rolls 
B. Saliva ejector
C. Rubber dam 
D. Paper napkin


The correct answer is C. Rubber dam.





It is not possible to properly accomplish operative dentistry without control of mouth moisture. Moisture control refers to the exclusion of saliva, gingival sulcular fluid, and gingival bleeding from the operating field. It also involves preventing or limiting the spray from the handpiece and restorative debris from being swallowed or aspirated by the patient. he rubber dam, suction devices, and absorbents are variously effective in controlling moisture. Use of the rubber dam as an optimum means of gaining moisture control is recommended.

The finish line used in complete metal cast crown is:

  # The finish line used in complete metal cast crown is:
 A. Chamfer
 B. Chamfer with bevel
 C. Feather Edge
 D. Shoulder



The correct answer is A. Chamfer.

Indications of Chamfer Finish Line
- Cast metal restorations
- Lingual aspect of metal ceramics

 Advantages of Chamfer finish line:
- Conservative 
- Good marginal adaptation
- Provides bulk

Disadvantages of Chamfer finish line:
- Improper fabrication may result in an unsupported tip