Evaluation of the photodynamic therapy with riboflavin and curcumin on shear bond strength of orthodontic bracket: An in vitro study.

AIM AND OBJECTIVES

The aim of this study was to evaluate the effect of antimicrobial photodynamic therapy (aPDT) with riboflavin and curcumin on the shear bond strength (SBS) of the orthodontic brackets.

METHOD AND MATERIAL

A total of 45 human premolar teeth were used in this study. All teeth were examined under a stereomicroscope. The samples were divided into 3 groups including no intervention (control group), aPDT with riboflavin and 460 nm LED and aPDT with curcumin and 460 nm LED. After aPDT procedure, orthodontic brackets were bonded to enamel surfaces. Then, the samples were thermocycled for 3000 cycles. The brackets were then debonded using a universal testing machine. The adhesive remnant index (ARI) score was assessed. ANOVA with Post-hoc test was used to compare the SBS values between groups.

RESULTS

The highest SBS mean value was presented in curcumin group (25.95±3.68) whereas, the lowest SBS mean value was observed in riboflavin group (22.19±4.73). The mode of failure was mostly score 1 and score 2 in all groups. There was no significant difference in SBS values and ARI score between groups. Scanning electron microscope images of the curcumin and control groups showed the honey comb structure, while the microscopic view of the riboflavin group lacked this structure and had less porosity and irregularity after etching.

CONCLUSION

Riboflavin and curcumin mediated antimicrobial photodynamic therapy both have acceptable bond strength of the orthodontic brackets and can be used before bonding to reduce inflammation and elimination of microbial biofilms.