Dentosphere : World of Dentistry

#MCQ 19 - Selective Pressure Impression Technique is indicated in: A. Firm healthy Mucosal covering over the ridge B. Flabby ridges C. Knife edge with movable mucosa D. When sharp bony spicules are present in the ridge Ans: A. Firm healthy mucosal covering over the ridge Mucostatic Impression Technique is indicated for options B,C and D. CLICK HERE TO VIEW  ALL MCQS

#MCQ 18 - The main Purpose of covering the retromolar pad area is: A. Stability B. Retention C. Support D. Contraction Ans: B. Retention Retromolar pad: - gives the peripheral seal of a lower denture - gives distal extension limit - gives the height of the occlusal plane - relieving area since it contains three muscles and aids the stability of the denture Though retromolar pad provides stability, support and retention, the main objective of covering it is retention. CLICK HERE TO VIEW  ALL MCQS

#MCQ 17 - Passive Impression Technique Involves: A. Impression with silicone B. Impression compound C. Impression Plaster D. Alginate Answer: C. Impression Plaster Passive impression / Mucostatic Impression / Pressureless Impression technique records the tissues with minimal distortion and cause least possible displacement of tissues. There will be large amount of space between the tray and soft tissues and it uses very fluid type of impression material.  Impression material is the common material used in this technique.  CLICK HERE TO VIEW  ALL MCQS

#MCQ 16 - The amount of water needed to dissolve alpha and beta hemihydrate to react completely with 100 gram of calcium sulphate hemihydrates to convert it to calcium sulphate dihydrate is: A. 18.6 ml B. 22.2 ml C. 30.4 ml D. 45.3 ml Answer: A. 18.6 ml Water of reaction is same for all gypsum products i.e. 18.6 ml of water completely reacts with 100g of hemihydrate. But gauging water differs with the type of gypsum product. It is 45 ml for type III and 20 ml for type IV gypsum. CLICK HERE TO VIEW  ALL MCQS