Abstract
In this paper, the testing method of mode I fracture toughness for a dental adhesive resin was investigated varying the dimension of test specimen as a factor by using double cantilever beam(DCB)testing in which the test specimen had a metal/adhesive resin/metal construction.The major findings were as follows.In all test specimens, it was found that the values of fracture toughness(GIC, GIR)at the process of crack propagation were nearly constant.Therefore, it was found that the fracture toughness(GIC)at maximal load might only be measured to evaluate an adhesive resin. On the values of GIC, there was no effect from the dimensions of the test specimen, width(b=3, 5mm), thickness(2hm=2, 4mm)and initial crack length(a0=9-19mm).Such a testing method is more effective for evaluating the adhesive property of a adhesive resin.
