BOND STRENGTHS AND SEM MORPHOLOGY OF DENTIN-AMALGAM ADHESIVES

Purpose: To compare two one-bottle dentin bonding systems (DBS) with f ive multi-bottle DBS and one resin-modified glass-ionomer cement, rega rding their ability to bond spherical amalgam to freshly prepared dent in surfaces, in Vitro. The tested hypothesis was that one-bottle DBS w ould result in lower shear bond strengths than multi-bottle DBS. Mater ials and Methods: Eighty flat dentin bonding sites were prepared to 60 0-grit on middle dentin of caries-free human molars mounted In acrylic resin. The bonding surfaces were treated with eight different bonding systems, according to manufacturer's instructions: All-Bond 2; Amalga mbond Plus; Fuji Duet; One-Step/Resinomer; OptiBond; OptiBond FL; Prim e & Bond 2.0/Dyract Gem; and Scotchbond Multi-Purpose: Plus. A spheric al amalgam alloy (Megalloy) was hand-condensed on the treated surfaces . After thermocycling, the bond strengths were calculated by testing t he specimens in shear. Field-emission SEM examinations were carried ou t to evaluate the effects of different treatments on the dentin-amalga m interface of MO/OD cavities treated under the same protocol. Results : Statistical analysis revealed that Prime & Bond 2.0/Dyract Gem, Amal gambond Plus, and Scotchbond Multi-Purpose Plus resulted in the highes t shear bond strengths. The field-emission SEM observations showed acc umulation of the fluid adhesive resin underneath the amalgam restorati on, and an interpenetration between the amalgam and the adhesive resin , except for OptiBond and OptiBond FL. All systems, but Fuji Duet, for med an acid-resistant resin-dentin interdiffusion zone.