光强度对双固化树脂黏接剂与牙本质黏接强度的影响

Effects of irradiation intensity on the bond strength of dual-cure resin adhesive

目的比较不同光强度对双固化树脂黏接剂与牙本质的黏接强度影响。方法将40颗恒磨牙,暴露咬合面牙本质后随机分为两组,每组20颗牙。DC组用双重固化树脂黏接剂Clearfil DC Bond处理,SE组用光固化树脂黏接剂Clearfil SE Bond处理后,端端对接从近中方向光照。将黏接试样沿光照方向切成5片（1 mm/片,L1~5）,再将每片垂直黏接界面切出5个微拉伸样本（1 mm×1 mm）,测试两组黏接强度（m TBS）。结果随着穿透牙本质厚度增加,光强度降低导致黏接强度下降。部分样本在制备时发生界面折断,SE组存留样本L170%,L230%,L3~5为0;DC组L1~5分别为68%,86%,56%,44%和38%。SE组L1~5黏接强度分别为：（13.22±8.64）MPa,（7.49±3.88）MPa,0、0、0 MPa;DC组为：（11.25±4.11）MPa,（9.69±5.07）MPa,（8.13±4.88）MPa,（6.83±3.53）MPa和（5.56±2.95）MPa。两组表面两层黏接强度无统计学差异。结论双固化黏接剂与牙本质的黏接强度随着固化光穿透牙本质深度的增加而降低。

Objective To evaluate the intensity of irradiation after penetrating dentin, and compare the effects of cure-light on the micro-tensile bond strength （mTBS） of dual-cure dental adhesive. Methods The superficial dentin of occlusal surface （40 molars） were exposed and applied with Clearfil DC Bond（ A ） or Clearfil SE Bond （B）, then bonded together through light-cure from mesial de- jection. The bond specimens were cut into sticks（bonding area 1 mm × 1 mm） along the direction of light-cure （L1-5 ） , and tested with Micro-Tensile Tester for mTBS. The statistical analysis was performed using SPSS11. 0. Results After penetrating dentin of 1 mm and 2 mm thickness, the light irradiation decreased to （ 114 ± 28 ） mWcm- 2 and （28 ±11 ） mWcm - 2, respectively. Some stick samples were broken during preparation, and the fracture occurred at the bonding interface. The remaining samples were SE ： L1 70% , L2 30% , L3-L5 0% ; DC： L1 to L5 was 68%, 86%, 56%, 44% ,38% . The mTBS were （13.22 ±8.64） MPa （L1）, （7.49±3.88） MPa （L2） and 0 MPa （L3 and L4） for SE,（11.25 ±4.11） MPa （L1）, （9.69±5.07） MPa （L2）, （8.13 ±4.88） MPa （L3）, （6.83 ±3.53） MPa （ L 4） and （5.56 ± 2.95 ） MPa for DC. There was no significant difference between DC and SE regarding the mTBS of Ll and L2. Conclusions The mTBS of dual-cureresin adhesive decreased with the increase of cure-light penetrating depth of dentin.