COMPARISON OF SHEAR BOND STRENGTH OF THREE COMPOSITE RESIN REPAIR MATERIAL WITH CERAMIC AND COBALT CHROMIUM SURFACES AFTER VARIOUS SURFACE TREATMENTS - AN INVITRO STUDY

Aim:The objective of this study was to evaluate the shear bond  strength of  composite resin repair material with ceramic and cobalt chromium surfaces after various surface treatments  and the mode of bond failures by stereo microscope.
Materials An Methods: Thirty Ceramic and thirty Cobalt chromium  samples (10x10x2mm) were prepared .The samples were divided into three groups for ceramic -CI,CII,CIII and for metal -M1,MII and MIII .Three composite resin repair materials were used (1) Restorative composite (control)- [C Group ] ,(2)SHOFU P & R Ceramic repair kit-[S Group] (3) Ivoclar Ceramic Repair System intro pack after surface modification withintraoral sandblaster – [I Group].The composite material was added 6x4mm using a metal holder .All specimens were subjected to a standard shear load in the universal testing machine until fracture occurred. All   debonded samples were  examined  under stereomicroscope to determine the type of failure .The data was analyzed using one-way ANOVA test of variance and Post hoc comparison was applied at 95 % confidence level.
Results: Igroup showed the highest shear bond strength followed by S group in ceramic and metal samples. The C group showed least shear bond strength. The  predominant mode of failure among the C group in ceramic and Co Cr metal samples was adhesive failure , S Group showed 50% adhesive and 50% mixed type of failure in ceramic samples (CII) in cobalt chromium samples(MII),it showed 70 % adhesive and 30% mixed failure . I group showed 100% mixed failure in ceramic samples(CIII) group ,and 80% mixed and 20% adhesive failure in cobalt chromium samples(MIII).
Conclusion:The surface modified with intra oral sandblaster and repaired with Ivoclar ceramic repair kit showed the most favorable results in ceramic and cobalt chromium samples.