A comparison of the shear bond strength of orthodontic brackets bonded after enamel conditioning with sodium hypochlorite and papain gel: An in vitro study

Objectives: The objective of this research was to evaluate the effect of conditioning the enamel surface with 10% papain gel and 5.25% sodium hypochlorite (NaOCl) on the shear bond strength (SBS) of orthodontic brackets and correlate it with the conventional bonding mechanism utilizing a universal testing machine. Materials and Methods: Ninety extracted human premolars divided into three groups: In Group 1, treatment with 5.25% NaOCl for 60 s on enamel surface followed by etchant and primer application. In Group 2, treatment with 10% Papain gel for 40 s followed by etching and primer application. In Group 3, etching was followed by primer application. A universal testing machine was used to record the SBS of the orthodontic brackets. Results: About 5.25% NaOCl (15.10 ± 2.66) and 10% papain gel (15.66 ± 2.83) treatment on enamel before acid etching when compared to the control group (12.82 ± 2.03) increased the SBS with a statistically significant difference between them (P = 0.002, P < 0.001). The experimental groups, NaOCl (15.10 ± 2.66) and papain gel (15.66 ± 2.83) group, were comparable but did not show any statistically significant difference between them (P = 0.665). Conclusion: SBS of orthodontic brackets can be significantly increased if the enamel is deproteinized with 5.25% NaOCl and 10% papain gel before acid etching with 37% phosphoric acid compared to the conventional bonding technique. Deproteinizing enamel can be considered a cost-effective ally to increase orthodontic brackets' bond strength and thereby reduce the duration of orthodontic treatment.