Operative+dentistry+mcqs+pdf+new
1. The most critical factor for long-term bond stability of etch-and-rinse adhesives to dentin is: A) High solvent concentration B) Complete removal of the smear layer C) Maintaining dentin in a moist but not wet state D) Thick adhesive layer
Answer: C
Explanation: Overdrying dentin causes collagen collapse; overwetting dilutes the adhesive. "Wet bonding" (moist dentin) is essential for hybrid layer formation.
2. Universal adhesives can be used in etch-and-rinse, self-etch, or selective enamel etch modes. The highest enamel bond strength is achieved with: A) Self-etch mode (no separate etching) B) Selective enamel etch (phosphoric acid + universal adhesive) C) Rinse only with water D) Using a separate silane coupling agent only operative+dentistry+mcqs+pdf+new
Answer: B
Explanation: Selective etching of enamel with phosphoric acid (30-40 seconds) prior to universal adhesive provides micromechanical interlocking superior to self-etch mode on enamel.
3. Which of the following is a characteristic of "multimode" or "universal" adhesives (newer generation)? A) They require mandatory separate silane for glass ceramics B) They cannot be used in self-cure mode without an activator C) They contain MDP monomer for chemical bonding to zirconia D) All of the above Q: A new universal adhesive is used in
Answer: D
Explanation: Modern universal adhesives (e.g., Scotchbond Universal, Prime&Bond active) contain MDP (10-methacryloyloxydecyl dihydrogen phosphate) and often need a separate activator for self-cure composites without light.
Q: A new universal adhesive is used in "self-etch" mode on enamel. What is the primary concern?
A) Postoperative sensitivity
B) Incomplete resin tag formation
C) Hydrolytic degradation of the silane layer
D) Over-etching of peritubular dentin national boards (like NBDE
Answer: B) Incomplete resin tag formation
Explanation: Self-etch mode does not sufficiently demineralize enamel prism cores; selective etching of enamel margins is still recommended.
Operative Dentistry is the backbone of clinical dental practice. It involves the diagnosis, prevention, and restoration of defects in tooth structure, primarily caused by caries and trauma. For dental students preparing for university exams, national boards (like NBDE, INBDE, NDEB), or specialty entrance tests, mastering operative dentistry is non-negotiable.
However, the sheer volume of information—from Black’s principles of cavity preparation to the latest adhesive protocols—can be overwhelming. This is where Operative Dentistry MCQs PDF New resources become invaluable. In this article, we will explore why MCQs are the most effective study tool, what to look for in a new PDF, and where to find high-yield practice questions.