Effects of delayed application of mixed self-etching bonding agent on the tensile bond strength / 实用口腔医学杂志

ABSTRACT

Objective:To evaluate the influence of delayed application of mixed self-etching bonding agent on the tensile bond strength.Methods:Two "two-bottle,one-step" self-etching adhesives,Adper Prompt and Xeno III,were evaluated.The occlusal enamel of human third molar was cut out and the exposed dentin surface was divided in two halves by a 1 mm deep groove in the labial-lingual orientation to allow for evaluation of immediate application and delayed application(0.5,1,2,3,4,5 and 6 h) of mixed self-etching bonding agent in the same specimen,followed by composite resin built-up on the adhesive.The bonded specimens were sectioned into beams of approximately 0.9 mm2 and subsequently subjected to micro-tensile bond strength testing at a crosshead speed of 1.0 mm/min.Results:The specimens bonded with the Adper Prompt within 5 h after mixing showed no different and that with the Xeno III within 3 h after mixing showed no different.Conclusion:The effective period for "two-bottle,one-step" self-etching adhesives after mixing is limited.Different bonding agents have different effective periods.