Moslehifard Elnaz, Seyyedashrafi Mir Mahdi, Khosronejad Nasim
Department of Prosthodontics, Faculty of Dentistry, Tabriz University of Medical Sciences, Tabriz, Iran.
Department of Oral and Maxillofacial surgery, Urmia University of Medical Sciences. Urmia, Iran.
J Lasers Med Sci. 2021 Nov 6;12:e69. doi: 10.34172/jlms.2021.69. eCollection 2021.
This study was to assess the effect of various output parameters of laser treatment on roughening the surface of a commercial nickel-chromium (Ni-Cr) alloy as compared to the sandblasting technique. Ninety-six disk-shaped (5 mm diameter and 2 mm thickness) specimens in total were made of a nickel-chromium alloy by using the lost-wax technique. Air-abrasion surface treatment was used for sixteen specimens. Specimens were divided into six groups; one of them was sandblasted and the rest were irradiated by different Nd:YAG laser output parameters as follows: Group A: energy: 122 mJ, frequency: 20 Hz, irradiation duration: 20 seconds, spot size: 1.5 mm; Group B: energy: 122 mJ, frequency: 20 Hz, irradiation duration: 20 seconds, spot size: 3.5 mm; Group C: energy: 122 mJ, frequency: 10 Hz, irradiation duration: 20 seconds, spot size: 3.5 mm; Group D: energy: 102 mJ, frequency: 10 Hz, irradiation duration: 20 seconds, spot size: 3 mm; Group E: energy: 102 mJ, frequency: 20 Hz, irradiation duration: 20 seconds, spot size: 3 mm. The surface roughness of all surface-treated specimens was evaluated by using a profilometer, and their average roughness (Ra) was calculated. The average value of each group was analyzed by test and one-way ANOVA (SPSS 17). Significant differences (<0.05) were observed between the study groups. The highest Ra was achieved for the sandblasted group. The Ra value in group C was the highest value among the laser-etched groups. Based on the results, Nd:YAG laser irradiation increases surface roughness, but it is not as efficient as the sandblasting method as a gold standard.
本研究旨在评估与喷砂技术相比，激光治疗的各种输出参数对商用镍铬（Ni-Cr）合金表面粗糙度的影响。总共96个圆盘形（直径5毫米，厚度2毫米）试样采用失蜡法由镍铬合金制成。对16个试样进行了空气磨蚀表面处理。试样分为六组；其中一组进行喷砂处理，其余组采用不同的Nd:YAG激光输出参数进行照射，具体如下：A组：能量：122 mJ，频率：20 Hz，照射持续时间：20秒，光斑尺寸：1.5毫米；B组：能量：122 mJ，频率：20 Hz，照射持续时间：20秒，光斑尺寸：3.5毫米；C组：能量：122 mJ，频率：10 Hz，照射持续时间：20秒，光斑尺寸：3.5毫米；D组：能量：102 mJ，频率：10 Hz，照射持续时间：20秒，光斑尺寸：3毫米；E组：能量：102 mJ，频率：20 Hz，照射持续时间：20秒，光斑尺寸：3毫米。使用轮廓仪评估所有表面处理试样的表面粗糙度，并计算其平均粗糙度（Ra）。通过检验和单因素方差分析（SPSS 17）对每组的平均值进行分析。研究组之间观察到显著差异（<0.05）。喷砂组的Ra值最高。C组的Ra值是激光蚀刻组中的最高值。基于这些结果，Nd:YAG激光照射会增加表面粗糙度，但作为金标准，它不如喷砂方法有效。
