Year : 2015

Volume : Volume 5

Issue : Issue 2

Address for correspondence :
Dr. Sumit Singh Phukela
phukelasumit@yahoo.com

Abstract

Background:  Aims and objective: Poly-methyl-metacrylate resin has been used commonly for denture bases. Polymerisation shrinkage and release of thermal stresses are the major disadvantages exhibited of these materials. The present study was conducted to check the effect of curing mode on  the adaptation accuracy of heat cured  and  microwave processed acrylic resin .  Methodology :30 maxillary  acrylic bases (2 mm thick) were made on cast model. These specimens were divided into 3 groups. Group 1: control,  conventional heat cure PMMA  cured by water bath method (short cycle) Group 2; Conventional heat cure PMMA samples cured by water bath method (Long cycle) Group 3; microwave acrylic resin samples cured by microwave energy (350 W for 6 min). The base/ cast sets were sectioned transversally in the posterior palatal seal zone. The measurements were made at the right marginal limit, left marginal limit, right ridge crest, left ridge crest and the palatal midline. The existence of gaps between the casts and acrylic was assessed using a stereomicroscope. Results: There was no significant difference between conventional heat cure PMMA samples cured by water bath method (Long cycle) and microwave acrylic resin samples cured by microwave energy.   Conclusion: The greatest discrepancy was seen in conventional heat cure PMMA samples cured by water bath (short cycle) and lowest discrepancy was seen with the microwaveable acrylic resin samples cured by microwave energy (350 W for 6 min).

Keywords: Adaptation accuracy Microwave,  Denture base material,Poly-methyl-metacrylate.