Effect of the type of acidic monomer on the bond durability of two-bottle type ceramic primer

Abstract

Ceramic primers consisting of γ-methacryloxypropyl trimethoxysilane (γ-MPS) and either 4-methacryloyloxyethyl trimellitate (4-MET) or 10-methacryloyloxydecyl dihydrogen phosphate (MDP) are useful for facilitating bonding of resin cement to silica-based ceramic surfaces. However, bond stability at the resin-ceramic interface differs among commercial ceramic primers. To determine the ability of 4-MET or MDP to hydrolyze the methoxy group in γ-MPS, the author designed two-bottle experimental ceramic primers comprising γ-MPS solution and an activator solution of 4-MET or MDP. The effects of the type of acidic monomer on contact angle and ceramic bond durability of resin were investigated. MDP and 4-MET promoted chemisorption of γ-MPS on the ceramic surface and enhanced the ceramic bond strength of the resin. However, thermo-cycling decreased ceramic bond strengths, as reflected by the increased number of bonded specimens that exhibited interfacial resin failure. Bond strength was greater for 4-MET-activated ceramic primer than for the MDP-activated ceramic primer, although most bonded specimens exhibited interfacial resin failure. Degradation behavior differed between the 4-MET-activated and MDP-activated ceramic primers.