Effect of Cisplatin-Titanate Nanoparticles on Composite-Tooth Bond Strength

Objective: Nanoparticles of monosodium titanate (nMST) loaded with Cisplatin (nMST-CisPt) may reduce recurrent decay at tooth-composite margins through antibacterial properties. Our objective was to determine if adding nMST-CisPt to the All-Bond 2^® adhesive system altered the shear bond strength of resin composite to enamel or dentin.

Method: nMSTs were synthesized using a sol-gel process and loaded with Cisplatin by a wet-chemistry method. Axial surfaces of 48 extracted human molars were prepared to create flat enamel or dentin surfaces  8mm in diameter and were divided into 3 groups. For enamel specimens, one etched surface was bonded with All-Bond 2® adhesive modified (10wt%) with nMST or nMST-CisPt; the other etched surface was a control using unaltered adhesive. For the dentin specimens, a similar protocol was followed except that the nMSTs or nMST-CisPt were added to the All-Bond 2® primer . Resin composite (Filtek^TMSupreme Plus) was injected into a gel capsule and added perpendicularly to the coated specimen surface.  Specimens were light-cured for 120s and stored in water (37°C, 24h). Shear bond strength was measured with a universal testing machine (n=16, CHX=5mm/min) and the peak shear force at failure was recorded. Power analysis was used to calculate the minimum sample size required.  Differences among groups were identified using ANOVA and Tukey post-hoc analyses (a≤.05).

Result: The mean (SD) shear bond values ranged (all conditions) from 287 (70) to 307 (36) N. No statistically significant differences in failure force were observed among tested groups (P=0.70). Combined adhesive and cohesive failure patterns were observed with optical microscope.

Conclusion: Within the limitations of this study, the addition of either nMST or nMST-CisPt to All-Bond2® did not affect the shear bond strength between composite and human dentin or enamel.