COMPARATIVE EVALUATION OF THE EFFECT OF DIFFERENT DENTIN DISINFECTION PROTOCOLS ON THE SHEAR BOND STRENGTH OF TWO RESTORATIVE MATERIALS- AN IN VITRO STUDY

Introduction: After cavity preparation and caries removal, microorganisms remain on dentinal surfaces. Disinfection of dentin surface prior to any restorative therapy is important for the longevity of the treatment. However, these dentin disinfection methods should itself not interfere with the adhesion of the restorative material.

Objectives: To compare the effect of different dentin disinfections on the bond strength of two restorative materials.

Methods: 72 extracted premolars were sectioned horizontally from one third of the coronal crown to expose flat dentin surface and embedded into cold cure acrylic. They were randomly divided into 3 groups with each group having 24 specimens. Group I- CTRL with no disinfection protocol (12 for RMGIC and 12 for glass hybrid) Group II- Disinfection with 2% chlorhexidine Group III- Disinfection with GLUMA desensitize.Then a predetermined dimension 3×3mm of RMGIC and glass hybrid material was bonded to the pre-treated dentin surfaces. The samples were stored in distilled water for 24 hours at room temperature. Each sample was tested for SBS using UTM.

Results: Gluma with Equia Forte showed the highest shear bond strength (SBS) among all groups (37.91 MPa). Gluma disinfection significantly improved SBS compared to chlorhexidine (CHX), especially with glass hybrid materials. EF outperformed RMGIC in both CHX and Gluma groups. CHX groups showed the lowest SBS, with no significant difference between RMGIC and EF. In contrast, Gluma groups showed a significant SBS difference between the two materials.

Conclusion: The use of GLUMA and CHX based cavity disinfectants do not significantly interfere with adhesion of RMGIC and glass hybrid material.