Evaluation of etch patterns and bond strength after using different enamel conditioners with and without deproteinizing agent: an in vitro study

Objective: The objective of this study was to compare etch patterns, shear bond strength and ARI scores using different enamel conditioners with and without deproteinizing agent. Study Design: A total of 125 human premolars were divided into 5 groups (n = 25) as follows: Group A, B1, C1 in which teeth are etched with 37% phosphoric acid, 10% maleic acid, 20% lactic acid for 20 seconds respectively. In Groups B2 and C2, etchants were same as B1 and C1 but enamel deproteinization with 5.25% sodium hypochlorite was done for 1 minute before enamel etching. Etching patterns were then evaluated in SEM, bond strength was examined with universal mechanical test machine and ARI scores were evaluated to check the bracket debonding interface. Data was analyzed statistically. Results: Group B2 showed superior SBS, more of type 1 etching patterns and debonding occurring at bracket adhesive interface compared to the control group (A), whereas the Group C1showed lowest mean SBS, type 4 etching patterns and debonding occurring at the enamel adhesive interface. Group B2 and C2 showed higher SBS and better etching patterns compared to the Group B1 and C1 where deproteinizing agent not was used. Conclusions: Enamel deproteinization with 5.25% sodium hypochlorite showed improvement in etching patterns and increased shear bond strength of orthodontic brackets bonded with alternative acids to etch the enamel surface.