ABSTRACT:
Objective: to evaluate the microshear bond strength of self-adhesive composite versus conventional resin-based fissure sealant using different enamel pretreatment protocols.

Methods: A total of 50 sound human premolars extracted for orthodontic reasons were used for the current study. Teeth roots were sectioned and crowns were mounted in self-cured acrylic resin blocks. The teeth were randomly divided into five equal groups according to the tested materials and enamel pre-treatment protocols as follow; Group I: self-adhesive flowable composite (Constic) without enamel pre-treatment, Group II: Constic composite with prior enamel etching, Group III: Constic composite with prior enamel etching and adhesive resin application, Group IV: conventional resin-based fissure sealant (Ultraseal XT plus) with prior enamel etching, Group V: Ultraseal XT plus fissure sealant with prior enamel etching and adhesive resin application. Microshear bond strength (μSBS) was tested using a universal testing machine. Data were tabulated and statistically analyzed using One-way ANOVA followed by Tukey's post hoc test.

Results: There was a statistically significant difference between microshear bond strength of the five tested groups. Group III showed the highest microshear bond strength value followed by Group V, then Group II and Group IV while Group I showed the lowest microshear bond strength value.

Conclusions: Self-adhesive composites have superior performance than conventional resin-based fissure sealants when using enamel pretreatment protocols. The use of enamel etching and adhesive resin before the application of self-adhesive composite and conventional resin-based fissure sealants was beneficial in improving the microshear bond strength.