A. H2O interferes with hygroscopic expansion
B. H2O inhibits polymerization of dental resin
C. H2O interferes with Crystallization of dihydrate
D. Gypsum is slightly soluble in water and the surface of the cast will be eroded
Related Mcqs:
- Model plaster (white) used to cast study models before mixing with water, is largely composed of____________?
A. CaO
B. CaCO3
C. (CaSO4)2-½H2O
D. CaSO4-2H2O - Back pressure porosity can be avoided by________________?
A. Using asbestos linear
B. Placing the sprue at least one quarter inch away form the end of casting ring
C. Preventing rapid heating the investment in burnout oven
D. Using a short and wide sprue - The following drugs are avoided with warfarin ______________?
A. Antacids
B. Benzodiazepine
C. Nsaid’s like Ibuprofen
D. Codeine, dihydrocodeine, paracetmol - A patient taking beta-blocker preoperatively, at induction of anaesthesia with fentanyl. Which muscle relaxant should be avoided ?
A. Pancuronium
B. Rocuronium
C. Vecuronium
D. Atracurium - Drug to be avoided in a patient allergic to penicillin is_____________?
A. Sulphonamide
B. Tetracycline
C. Ampicillin
D. Cholarmphenicol - Morphine a powerful opioid analgesic drug should be avoided in all the following conditions except____________?
A. Left ventricular failure
B. Bronchial asthma
C. Constipation
D. A & C - Following analgesic combination should be avoided ?
A. Aspirin and Codeine
B. Paracetamol and Dextropropoxyphene
C. Ibuprofen and Paracetamol
D. Ibuprofen and DIclofenac - Aspirin is avoided in children with influenza infection because of association______________?
A. Reye’s syndrome
B. Nausea
C. Diarrhoea
D. Acid-base imbalance - A rough / Chalky surface of the cast is due to_______________?
A. Not waiting for 20 min before pouring
B. High speed accelerator
C. Air incorporation in the mix
D. All of the above - The impression for a diagnostic cast of a partial edentulous mouth should be taken in_______________?
A. Impression wax
B. Modelling compound
C. Hydro-colloid
D. Hydro cal
