THE EFFECT OF VARIOUS STORAGE METHODS AND MEDIA ON SHEAR-BOND STRENGTHS OF DENTAL COMPOSITE RESIN TO BOVINE DENTIN

A variety of media and methods have been used to store teeth used in b ond-strength studies of resin restorative materials to dentine. This s tudy examined the effect of 2 months of storage using 11 different met hods and media on the shear-bond strength of Z100 resin composite to b ovine dentine mediated by Scotchbond Multi Purpose adhesive. Freshly h arvested teeth were used as controls. The results showed that 7 of the 11 storage methods or media were similar in shear-bond strengths and bond-failure characteristics. Four of the 11 methods (irradiation, or storage in thymol, methanol, and glutaraldehyde) resulted in significa ntly lower shear-bond strengths and atypical shear-bond failure, indic ating that these are the least desirable methods of tooth storage for studies of this type. This study has further shown that if insufficien t numbers of fresh teeth are available for studies of shear-bond stren gth, then freezing is the preferred method of storage for the registra tion of high shear-bond strengths. It is also apparent that further in vestigations are needed to examine what post mortem changes occur in d entine, whether these changes are modified by various storage conditio ns, and whether they have any significant effect on bonding of resin c omposites. (C) 1998 Elsevier Science Ltd. All rights reserved.