Effect of malachite green, ocimum sanctum, and Er, Cr: YSGG laser on antimicrobial activity against S.mutans and CAD disinfection bonded to resin restoration

Aims: Evaluation of survival of S.mutans and shear bond strength (SBS) of adhesive restorative material bonded to carious affected dentin (CAD) after using cavity disinfectant i.e., Er, Cr: YSGG (ECYL), (Nd: YAG) (NYL), Mal-achite green (MG), Ocimum sanctum (OS) in comparison to the conventional control chlorhexidine gluconate (CHX).Materials and methods: Seventy-five caries-affected mandibular third molars having ICDAS scores 4 and 5 were included. Carious infected dentin was eliminated and CAD surface was obtained. On twenty-five samples, an uncontaminated suspension of S. mutans strain ATCC 35,668 in Brain-Heart Infusion broth (BHI) was obtained after 12 h of incubation at 37 degrees C. Based on the disinfection regime used to sterilize the CAD surface, all the specimens were allocated into five different groups. (n = 15) Group 1: CAD disinfected with CHX, Group 2: CAD disinfected with ECYL, Group 3: CAD disinfected with NYL, Group 4: CAD disinfected with MG, and Group 5: CAD disinfected with OS. An assessment of the survival rate of S. mutans was performed. Fifty specimens were smeared with single-step adhesive bond followed by restoring the CAD surface using packable composite. SBS and failure mode were determined using a universal testing machine and stereomicroscope at 40x magnification. ANOVA and post-hoc Tukey-Kramer test was used for data analysis p = 0.05.Results: Group 1: CHX-treated specimens displayed the lowest bacterial viability (0.11 +/- 0.03 CFU/mL). However, group 4: MG exhibited the highest bacterial survival (0.15 +/- 0.09 CFU/mL). The highest and lowest SBS of resin adhesive bonded to disinfected CAD surface were exhibited by (group 5: OS) (21.48 +/- 1.39 MPa) and (group 3: NYL) (16.41 +/- 0.90 MPa) respectively (p>0.05).Conclusion: Ocimum sanctum seems to be promising in terms of its antibacterial efficacy against S.mutans and positive impact on SBS of resin adhesive to CAD surface.