EFFECT OF THERMOCYCLING ON SURFACE ROUGHNESS OF DENTURE BASED SELF CURE RESIN

Abstract

Introduction: The surface properties of acrylic resins such as roughness, hardness, surface energy, and wettability may affect plaque accumulation. Acrylic resin denture bases have been traditionally polished with water and pumice and also by using conventional resin polishing kits. In recent times, surface sealants have been in use on resin-based materials to eliminate surface defects and to increase wear and stain resistance.

Aim: The aim of the present study was to evaluate the effect of thermocycling on the surface roughness of denture based self cure resin.

Materials and Methods: Ten pellets of self cure resin (1010  4 mm) of which five samples were from DPI resin and other five samples were  from Ivlorac resin for an in vitro study. Then the four samples were subjected to the thermocycling process and one sample was left for control. Then the surface roughness was evaluated using a surface roughness tester (Mitutoyo Sul Ltda) with a standard cut off value of 0.8 mm and a speed of 0.10 mm/s. The pre surface roughness and post surface roughness was checked by a stylus profilometer.

Result: Ra value (Roughness average), obtained prior to  thermocycling for self cure resin samples were slightly reduced after subjecting to thermocycling. Rq value( Root mean square roughness ), prior to thermocycling surface roughness of self cure resin samples had significantly reduced compared to after subjecting to thermocycling. Rz value of pre thermocycling surface roughness for self cure resin had slight variations when compared after subjecting to thermocycling. The P-value obtained for pre and post surface roughness was  (> 0.005; not statistically significant).

Conclusion: The current study concludes that the surface roughness of self cure resin was  increased after subjecting to thermocycling. Thus it can be concluded that thermocycling affects the surface roughness of  light cure resin.