Abstract：
This study assessed alterations in sensitivity among symptomatic noncarious cervical lesions (NCCLs) following the application of 3 low-level diode laser wavelengths before composite restoration. It analyzed the changes in dentin topography using a scanning electron microscope (SEM).
Nine patients with 36 NCCLs were randomly assigned intra-individually to 4 groups based on the laser wavelength: laser simulation, 445 nm, 660 nm, and 970 nm. Cavity preparation, irradiation, and composite restoration were performed for each lesion. Sensitivity to cold stimuli was recorded using a visual analog scale (VAS) before the intervention (baseline) and at 1 day, 14 days, 1-, 3-, and 6-month. Pulp sensibility was recorded using an electrical pulp tester (EPT) at baseline, before treatment, and at 3- and 6-month. Additionally, an in vitro examination was performed on 12 extracted human molars to yield 12 dentin discs. Each disc was randomly divided into 4 quadrants to receive the same laser wavelengths to determine the diameters of the tubules using SEM. Results were analyzed statistically for clinical studies by the Friedman test, while ANOVA (RM-ANOVA) was conducted in-vitro, followed by the Bonferroni test in the case of significance (P < .05).
VAS readings decreased across all groups, with a significant decrease observed for 660 nm and 970 nm from 14 days to 6-month, while at 445 nm there was a significant decrease at 6-month compared to the control (P < .05). EPT showed a significant decrease in pain threshold levels at 660 nm and 970 nm at 3- and 6-month, while 445 nm showed a significant decrease at 6-month compared to the control (P < .05). The mean tubular diameter at 445 nm decreased, with no significant difference from the control, whereas a significant decrease was found at 660 nm and 970 nm compared to the control (P < .05).
Prior to composite restoration in symptomatic NCCLs, diode lasers with a wavelength of 660 nm showed the highest reduction in sensitivity, followed by 970 nm, whereas 445 nm diode lasers showed the least reduction. Additionally, diode lasers with wavelengths of 660 and 970 nm reduced the width of the dentinal tubules (DT) without inducing melting, as viewed under SEM.
Nine patients with 36 NCCLs were randomly assigned intra-individually to 4 groups based on the laser wavelength: laser simulation, 445 nm, 660 nm, and 970 nm. Cavity preparation, irradiation, and composite restoration were performed for each lesion. Sensitivity to cold stimuli was recorded using a visual analog scale (VAS) before the intervention (baseline) and at 1 day, 14 days, 1-, 3-, and 6-month. Pulp sensibility was recorded using an electrical pulp tester (EPT) at baseline, before treatment, and at 3- and 6-month. Additionally, an in vitro examination was performed on 12 extracted human molars to yield 12 dentin discs. Each disc was randomly divided into 4 quadrants to receive the same laser wavelengths to determine the diameters of the tubules using SEM. Results were analyzed statistically for clinical studies by the Friedman test, while ANOVA (RM-ANOVA) was conducted in-vitro, followed by the Bonferroni test in the case of significance (P < .05).
VAS readings decreased across all groups, with a significant decrease observed for 660 nm and 970 nm from 14 days to 6-month, while at 445 nm there was a significant decrease at 6-month compared to the control (P < .05). EPT showed a significant decrease in pain threshold levels at 660 nm and 970 nm at 3- and 6-month, while 445 nm showed a significant decrease at 6-month compared to the control (P < .05). The mean tubular diameter at 445 nm decreased, with no significant difference from the control, whereas a significant decrease was found at 660 nm and 970 nm compared to the control (P < .05).
Prior to composite restoration in symptomatic NCCLs, diode lasers with a wavelength of 660 nm showed the highest reduction in sensitivity, followed by 970 nm, whereas 445 nm diode lasers showed the least reduction. Additionally, diode lasers with wavelengths of 660 and 970 nm reduced the width of the dentinal tubules (DT) without inducing melting, as viewed under SEM.
摘要：
这项研究评估了在复合修复前应用3个低水平二极管激光波长后，有症状的非龋齿宫颈病变（NCCL）的敏感性变化。使用扫描电子显微镜（SEM）分析了牙本质形貌的变化。
根据激光波长，将9例36例NCCL患者随机分为4组：激光模拟，445nm,660nm,和970nm。腔准备,辐照，并对每个病变进行复合修复。在干预前（基线）和第1天使用视觉模拟量表（VAS）记录对冷刺激的敏感性，14天,1-,3-,和6个月。使用电子纸浆测试仪（EPT）在基线记录纸浆灵敏度，治疗前,在3个月和6个月。此外,对12颗提取的人磨牙进行了体外检查，得到12个牙本质盘。将每个盘随机分成4个象限以接收相同的激光波长,从而使用SEM确定小管的直径。通过弗里德曼检验对临床研究的结果进行统计分析，而方差分析(RM-ANOVA)是在体外进行的，在显著性的情况下进行Bonferroni检验(P<0.05)。
所有组的VAS读数均下降，从14天到6个月观察到660nm和970nm的显着下降，而在445nm时，与对照组相比，6个月时有显着下降（P<0.05）。EPT在3个月和6个月时在660nm和970nm处显示疼痛阈值水平显着降低，而445nm与对照组相比，在6个月时显示出显着降低（P<0.05）。445nm处的平均管径减小,与对照组没有显着差异，而与对照组相比，在660nm和970nm处发现显着下降（P<0.05）。
在有症状的NCCL进行复合修复之前，波长为660nm的二极管激光器显示出最高的灵敏度降低，其次是970纳米，而445nm二极管激光器显示出最小的减少。此外,波长为660和970nm的二极管激光器减小了牙本质小管（DT）的宽度，而不会引起熔化，在SEM下观察。
根据激光波长，将9例36例NCCL患者随机分为4组：激光模拟，445nm,660nm,和970nm。腔准备,辐照，并对每个病变进行复合修复。在干预前（基线）和第1天使用视觉模拟量表（VAS）记录对冷刺激的敏感性，14天,1-,3-,和6个月。使用电子纸浆测试仪（EPT）在基线记录纸浆灵敏度，治疗前,在3个月和6个月。此外,对12颗提取的人磨牙进行了体外检查，得到12个牙本质盘。将每个盘随机分成4个象限以接收相同的激光波长,从而使用SEM确定小管的直径。通过弗里德曼检验对临床研究的结果进行统计分析，而方差分析(RM-ANOVA)是在体外进行的，在显著性的情况下进行Bonferroni检验(P<0.05)。
所有组的VAS读数均下降，从14天到6个月观察到660nm和970nm的显着下降，而在445nm时，与对照组相比，6个月时有显着下降（P<0.05）。EPT在3个月和6个月时在660nm和970nm处显示疼痛阈值水平显着降低，而445nm与对照组相比，在6个月时显示出显着降低（P<0.05）。445nm处的平均管径减小,与对照组没有显着差异，而与对照组相比，在660nm和970nm处发现显着下降（P<0.05）。
在有症状的NCCL进行复合修复之前，波长为660nm的二极管激光器显示出最高的灵敏度降低，其次是970纳米，而445nm二极管激光器显示出最小的减少。此外,波长为660和970nm的二极管激光器减小了牙本质小管（DT）的宽度，而不会引起熔化，在SEM下观察。
