Etching depth after 30 sec for orthodontic bracket with orthophosphoric acid is_________________?

Related Mcqs:

1. Acid-etching is done for_______________?

   A. 30 seconds
   B. 60 seconds
   C. 90 seconds
   D. 120 seconds

2. Most advantageous indication of acid etching is______________?

   A. Decrease micro leakage
   B. Decrease polymerization shrinkage
   C. Decrease coefficient of thermal expansion
   D. Decrease porosity in restorative material

3. When restoring a tooth with resin material, acid etching can do all of the following except______________?

   A. Increase the surface area
   B. Permit chemical bonding between resin and enamel
   C. Create surface irregularities in enamel for better mechanical retention of resin
   D. Condition the tooth surface for better wetting

4. 18-B Stainless steel orthodontic wire has_______________?

   A. 18% Nickel 8% Chrominum
   B. 18% Chromium 8% Nickel
   C. 18% Chromium 8% Cobalt
   D. 18% Carbon 8% Iron

5. Stainless steel orthodontic wire can be hardened by________________?

   A. Tempering
   B. Work hardening
   C. Age hardening
   D. Precipitation hardening

6. Ability of an orthodontic wire to spring back to its original shape is evaluated by_____________?

   A. Brittleness
   B. Resilience
   C. Tensile strength
   D. Toughness

7. Etching of dentin does not include_____________?

   A. Removal of smear layer
   B. Exposure of collagen fibers
   C. Opening of dentinal tubules
   D. Increases surface energy

8. Which acid is formed in the citric acid cycle ?

   A. Oxaloacetic acid
   B. Glutamic acid
   C. Nitric acid
   D. None of the above

9. The reducing end of glutathione, the amino acid is_________________?

   A. Glycine
   B. Leucine
   C. Lycie
   D. Valine

10. Ethoxy benzoic acid increases the strength and solubility of the cement______________?

    A. Zinc oxide eugenol
    B. Polycarboxylate cement
    C. Zinc phosphate cement
    D. Silicate cement