Shear bond strength of posterior comp-osite cores


This study was designed to evaluate the shear bond strength(SBS) of posterior composite resin cores to tooth surface usingtwo dental adhesives and two retentive means.Thirty extracted permanent molars were used for this purpose.They were made flat by removing the occlusal one thirdusing “stone grinding wheal”. Teeth were then randomly dividedinto six groups:Groups I and IV: Scotchbond Multipurpose Plus (SbMP)and All bond 2 dental adhesives were used for groups I and IVrespectively to adhere composite to the flat tooth surface with noretentive mean as the control group.Groups II and V: A circumferential slot was prepared andcomposite attached to the tooth using SbMP and All bond 2 forgroups II and V respectively.Groups III and VI: Four self threading pins were placedand composite adhered using SbMP and All bond 2 for groups IIIand VI respectively.After storage and thermal cycling, the SBS for each groupwas measured using “universal testing machine”.The results varied according to the retentive mean and dentaladhesive used. Groups with four pins produced the highest SBSand groups with no retentive mean showed the lowest SBS. Alsothe groups using All bond 2 adhesive generally had higher valueswhen compared with the same groups using SbMP dental adhesive.Within the limits of this study, it is indicated that when thehighest SBS is to be achieved, then All bond 2 dental adhesivewith pins should be used.