Laboratory evaluation of the tensile adhesive bond strength of a composite dental restorative system containing a surface--active comonomer to enamel and dentine.

A major problem in restorative dentistry is the lack of adhesion o f dental materials to tooth structure. Bowen (1965a) synthesized a surface-active como­ nomer, the reaction product of N-plienylglycine andglycidylmethacrylate, to serve as a coupling agent between dental restorative materials and tooth struc­ ture. A new composite restorative material, l)e Trey Cosmic, which incorporates Cosmic Bond (Bowen's surface-active comonomer) in a metered aerosol, has recently been introduced to the prof ession. The tensile adhesive bond strengths o f Cosmic to untreated and primed enamel and dentine surfaces were determined. All o f the 30 experimental bonds prepared on un­ treated enamel and dentine surfaces fa iled spontaneously under the experimental conditions em­ ployed in this investigation. Nine of the test specimens prepared on enamel surfaces primed with Cosmic Bond failed spontaneously and a mean tensile ad­ hesive bond strength o f 0,8 “h 0,4 N mm 2 was ob­ tained for the remaining 6 specimens. Only one of the 15 experimental bonds prepared on pruned dentine failed spontaneously and a mean tensile adhesive bond strength o f 3.4 ± 1,9 N mm 2 was recorded. Examination by scanning electron microscopy of the enamel anil dentine aspects and Cosmic surfaces of fractured bonds on primed surfaces, revealed evi­ dence o f some interaction at the interfaces of fractured bonds that recorded higher bond strengths. OPSOMMING