Study On Sclerotic Dentine Bonding Interface And Bond Strength

Objective : Aim of study is to compare the characteristic of the hybrid layer with total-etching adhesive agent on sound dentine and sclerotic dentine. The bonding interface were observed with transmission electron microscope (TEM) and bond strength were determined with Microtensile Tester.Methods: 20 molars with sclerotic dentine were extracted for periodontal disease , as experimental group. 20 premolars with normal dentine were extracted for orthodontic , as control group. All specimens were treated with 3M Single Bond total-etching adhesive system. The microstructures of dentine bonding interface were observed with transmission electron microscope (TEM) and determined bond strength with Microtensile Tester. Using SPSS11.5 software, obtained data were submitted to Independent-Samples T Test.Results: TEM showed that the hybrid layer were clear in sound dentine and sclerotic dentine, but the sclerotic dentine were a little thinner . Microtensile Tester of the bond strength values(M Pa)were as follows: control group(40.55±4.34); experimental group(38.43±2.28). Independent-Samples T Test revealed that control group was significant higher than experimental group(P<0.05).Conclusions: From TEM observation that: there were differences at the thickness of hybrid layer microstructure while using 3M Single Bond total-etching adhesive agent between sound or sclerotic dentine, the latter was a little thinner. And Microtensile Tester showed that the bond strength of sclerotic dentine was lower than sound dentine, which need pay much attention for every clinical dentist.