NANO- HYDROXYAPATITE (NANO-HAP) REINFORCED GLASS IONOMER CEMENT:- AN ALTERNATIVE RESTORATIVE MATERIAL.

Context: The lack of evidence regarding the best available material for restoring occlusal-proximal cavities in teeth leads to the development of new restorative material, with nanoparticles, in order to enhance mechanical properties, resulting in increased restoration longevity. Aim: To evaluate and compare the microhardness and shear bond strength of Nano Hap incorporated GIC and zirconomer with composite. Materials and Method: Thirty permanent molars were selected and assigned into three groups according to the restorative materials used. The restorative material build up over the dentin surface was done All the specimens were stored in distilled water for 24hrs before shear bond strength testing. For micro hardness evaluation, ten blocks of each restorative material were made according to the groups assigned. All these specimens were stored in distilled water for 24hrs before microhardness testing. Results: Nano- HAp GIC shows the highest Microhardness (112.79 VHN) followed by Composite (67.30) & Zirconomer (47.96) whereas the shear bond strength of Composite (53.37 MPa) was found to be the highest when compared to HAp (3.98) & Zirconomer (5.09). Conclusion: Highest shear bond strength values were seen in composites followed by Zirconomer and Nano-hydroxyapitite (GIC). Nano-HAp showed the highest mean micro hardness values when compared to Zirconomer and composites.