Department of Restorative Dentistry, Hacettepe University, School of Dentistry, Ankara, Turkey.
Lasers Med Sci. 2012 Jan;27(1):15-21. doi: 10.1007/s10103-010-0830-9. Epub 2010 Aug 31.
The purpose of this study is to evaluate microtensile bond strength (μTBS) of an etch-and-rinse adhesive to enamel and dentin after treatment with Er:YAG laser using different pulse durations. Extracted human molars were flattened to obtain enamel or dentin surfaces. The enamel specimens (E) were divided into nine groups and the dentin (D) specimens were divided into seven groups according to the surface treatments (n = 6). E-C: acid was applied according to the manufacturer's instructions and used as control, E-SSP: 120 mJ, 10 Hz, SSP (50 μs), E-SSP-A: 120 mJ,10 Hz, SSP+acid, E-VSP: 120 mJ, 10 Hz, VSP (100 μs), E-VSP-A: 120 mJ, 10 Hz, VSP+acid, E-SP: 120 mJ, 10 Hz, SP (150 μs), E-SP-A:120 mJ,10 Hz, SP+acid, E-LP:120 mJ,10 Hz, LP (300 μs), E-LP-A:120 mJ,10 Hz, LP+acid; D-C: acid was applied and used as control, D-SSP: 80 mJ, 10 Hz, SSP, D-SSP-A: 80 mJ, 10 Hz, SSP+acid, D-VSP: 80 mJ, 10 Hz, VSP, D-VSP-A: 80 mJ, 10 Hz, VSP+acid, D-SP: 80 mJ, 10 Hz, SP, D-SP-A: 80 mJ, 10 Hz, SP+acid. After application of etch-and-rinse adhesive, composite built-ups were created with a nanoceramic composite. Specimens were sectioned into serial 1-mm(2) sticks, and μTBS was measured in five sticks from each tooth randomly selected (n = 30). Failure modes were determined under a stereomicroscope. μTBS test data were analyzed by Welch-ANOVA followed by Dunnett's T3 tests and failure mode distributions were analyzed by Pearson Chi-square test (p = 0.05). μTBS was higher for enamel and dentin after additional acid etching than laser irradiation alone. E-SSP-A group exhibited the highest μTBS for enamel (p < 0.05). The D-SP-A group showed the highest value but the difference was not significant in comparison to D-C (p > 0.05). The μTBS of laser-irradiated but not acid-etched groups decreased when longer pulse durations were used. Laser treatment could enhance or impair the μTBS to enamel and dentin depending on the pulse duration used and additional acid application.
本研究旨在评估不同脉宽的 Er:YAG 激光处理后牙釉质和牙本质的微拉伸粘结强度（μTBS）。从离体磨牙上制备牙釉质和牙本质样本，磨平后用于实验。牙釉质样本（E）分为 9 组，牙本质样本（D）分为 7 组，根据表面处理方式进行分组（n = 6）。E-C 组：按说明书进行酸蚀处理，作为对照；E-SSP 组：采用 120 mJ、10 Hz、SSP（50 μs）处理；E-SSP-A 组：采用 120 mJ、10 Hz、SSP+酸蚀处理；E-VSP 组：采用 120 mJ、10 Hz、VSP（100 μs）处理；E-VSP-A 组：采用 120 mJ、10 Hz、VSP+酸蚀处理；E-SP 组：采用 120 mJ、10 Hz、SP（150 μs）处理；E-SP-A 组：采用 120 mJ、10 Hz、SP+酸蚀处理；E-LP 组：采用 120 mJ、10 Hz、LP（300 μs）处理；E-LP-A 组：采用 120 mJ、10 Hz、LP+酸蚀处理。D-C 组：酸蚀处理，作为对照；D-SSP 组：采用 80 mJ、10 Hz、SSP 处理；D-SSP-A 组：采用 80 mJ、10 Hz、SSP+酸蚀处理；D-VSP 组：采用 80 mJ、10 Hz、VSP 处理；D-VSP-A 组：采用 80 mJ、10 Hz、VSP+酸蚀处理；D-SP 组：采用 80 mJ、10 Hz、SP 处理；D-SP-A 组：采用 80 mJ、10 Hz、SP+酸蚀处理。然后应用酸蚀剂和全酸蚀剂，在牙釉质和牙本质表面制备粘结剂，用纳米陶瓷复合材料进行复合。将样本切割成 1-mm（2）的连续条状，从每个牙随机选择 5 个样本进行 μTBS 测量（n = 30）。在体视显微镜下观察失效模式。采用 Welch-ANOVA 对 μTBS 测试数据进行分析，然后采用 Dunnett's T3 检验，对失效模式分布采用 Pearson Chi-square 检验（p = 0.05）。与单独激光照射相比，牙釉质和牙本质经额外酸蚀后的粘结强度更高。E-SSP-A 组牙釉质的 μTBS 最高（p < 0.05）。D-SP-A 组的牙本质值最高，但与 D-C 组相比差异无统计学意义（p > 0.05）。当使用较长的脉宽时，激光照射但未酸蚀的组的 μTBS 降低。激光处理可根据所用脉宽和额外酸蚀应用增强或削弱牙釉质和牙本质的 μTBS。
