RESUMO
Objective To compare the influence of resin core on overall bending strength of fiber post-core restoration.Methods 60 mandibular first premolar extracted because of orthodontic treatment was selected.3M light -cured composite resin P60,medental dual-cured resin,pulpdent dual-cured resin combined with viva carbon fiber reinforced glass fiber post were applied.The changes of teeth in vitro were observed when strength was given on.Results The flexural strength of 3M light-cured composite resin was (80.182 ±9.512)N,Medental dual-cured resin was (87.805 ± 11.649) N,Pulpdent dual-cured resin was (85.458 ± 10.845) N.The flexural strength of 3 M light-cured composite resin was lower than that of medental dual-cured resin and pulpdent dual-cured resin (t =5.758,3.084,both P ＜ 0.05).There was no statistical differences of flexural strength between medental dual-cured resin and pulpdent dual-cured resin(t =0.718,P ＞ 0.05).There was large area of resin broken off after 3M light-cured composite resin core fracture.There was only fracture of medental dual-cured resin core and pulpdent dual-cured resin core.Conclusion The bending strength of dual-cured resin is better than that of highly filled light curing composite resin in large tooth hard tissue defect restoration with fiber post-core,and core broken off is rare.Dual-cured resin is better post-core materials.