Department of Orthodontics, Faculty of Dentistry, Shahid Sadoughi University of Medical Sciences, Yazd, Iran.
Dental Students Research Center, Faculty of Dentistry, Shahid Sadoughi University of Medical Sciences, Yazd, Iran.
Lasers Med Sci. 2020 Jul;35(5):1193-1203. doi: 10.1007/s10103-020-02970-y. Epub 2020 Feb 1.
This study investigated the combined effect of CO laser irradiation and Remin Pro paste on microhardness of enamel white spot lesions (WSLs). Seventy-eight intact premolars were randomly assigned into six groups and then stored in a demineralizing solution to create WSLs. Afterwards, the teeth in group 6 (negative control) remained untreated, while groups 1 and 4 were exposed to CO laser irradiation (20 Hz, 1 W, 30 s) and Remin Pro paste, respectively. In groups 2 and 3, the teeth were exposed to laser either before (group 2) or after (group 3) Remin Pro application. The teeth in groups 1 to 5 were then immersed in artificial saliva for 90 days while subjected to fluoride mouthwash and weekly brushing. Finally, the teeth were sectioned, and Vickers microhardness was measured at the enamel surface and at 50, 100, and 150 μm from the surface. One sample of each group was also examined with scanning electron microscope (SEM). Data were analyzed by two-way analysis of variance (ANOVA) and Tukey's test. The significance was set at 0.05. Laser irradiation followed by Remin Pro application (group 2) caused a significant increase in total WSLs' microhardness compared with laser alone (group 1) and control groups (P < 0.05). Microhardness at depths of 100 and 150 μm was also significantly greater in group 2 compared with those of group 3 and control groups (P < 0.05). Combined application of CO laser with Remin Pro paste, when laser is irradiated before the paste, is suggested for re-hardening of WSLs in deep layers of enamel.
本研究旨在探讨 CO2 激光照射联合 Remin Pro 糊剂对釉质白斑（WSL）显微硬度的联合作用。将 78 颗完整的前磨牙随机分为 6 组，然后储存在脱矿溶液中以形成 WSL。之后，第 6 组（阴性对照组）的牙齿未经处理，而第 1 组和第 4 组分别接受 CO2 激光照射（20 Hz，1 W，30 s）和 Remin Pro 糊剂。在第 2 组和第 3 组中，激光照射分别在 Remin Pro 应用之前（第 2 组）或之后（第 3 组）进行。第 1 组至第 5 组的牙齿随后在人工唾液中浸泡 90 天，同时使用含氟漱口水和每周刷牙。最后，将牙齿切片，在釉质表面和距表面 50、100 和 150 μm 处测量维氏显微硬度。每组还取一个样本用扫描电子显微镜（SEM）检查。数据采用双因素方差分析（ANOVA）和 Tukey 检验进行分析。显著性水平设为 0.05。激光照射后再应用 Remin Pro（第 2 组）与单独激光照射（第 1 组）和对照组相比，总 WSL 显微硬度显著增加（P<0.05）。第 2 组在 100 和 150 μm 深度处的显微硬度也显著高于第 3 组和对照组（P<0.05）。建议在釉质深层联合应用 CO2 激光与 Remin Pro 糊剂，先进行激光照射，再应用糊剂，以实现 WSL 的再硬化。
