Effects of restorative and adhesive curing methods on dentin bond strengths

Purpose : To evaluate the shear bond strengths of "one-bottle" adhesives to dentin when used with self-cared composite. Materials and Methods: 100 bov ine teeth were ground to expose superficial dentin, which was polished to 6 00-grit. The dentin was etched for 15 s with 35% phosphoric acid, rinsed, a nd blotted with tissue paper. The surface remained visibly moist for all sp ecimens. The following adhesives were applied to the etched dentin accordin g to manufacturers' directions: Scotchbond Multi-Purpose (in its visible li ght-cured [VLC] and self-cure modes) as a control, One-Step (VLC only), Opt iBond Solo Plus (VLC only), Prime & Bond NT (VLC) and Prime & Bond NT Dual- Cure. For each adhesive, specimens were bonded with a self-cure composite, while 10 were bonded with a VLC composite as a control. After 24 hrs water storage, shear bond strengths were determined using an Instron universal te sting machine. Data were analyzed using two-way ANOVA, Tukey's test, and St udent's t-tests. Results: Using the light-cured composite, mean bond streng ths ranged from 11.0 MPa for light-cured Prime & Bond NT to 26.3 MPa for Op tiBond Solo Plus. Using the self-cure composite, mean bond strengths ranged from 0.0 for light-cured Prime & Bond NT to 21.4 MPa for One-Step. Two adh esives, light-cured Prime & Bond NT and OptiBond Solo Plus, had significant ly lower bond strengths when used with the self-cure composite.