Eissa Nouran M, Elshourbagy Eman M, Gomaa Nahla E
Department of Orthodontic, Faculty of Dentistry, Tanta University, Tanta, Egypt.
Heliyon. 2022 Sep 30;8(10):e10752. doi: 10.1016/j.heliyon.2022.e10752. eCollection 2022 Oct.
The aim of this in vitro study was to evaluate the effect of NaF plus TCP with and without CO laser irradiation on management of demineralized enamel using microhardness test and digital microscopy.
Eighty intact extracted human premolar teeth were randomly divided into 4 groups (20/each). Each group was subjected to a demineralizing solution to create white spot lesion. was treated with 3M Vanish™. was irradiated with CO laser. was subjected to CO laser followed by 3M Vanish™. was treated by 3M Vanish™ then CO laser. The teeth were immersed in artificial saliva. Surface microhardness was measured for each tooth before demineralization at base line (M1 as a control), after demineralization (M2) and after management (M3). Comparison of microhardness values between groups was performed using one way ANOVA test with significant level (0.05) followed by multiple comparisons post-hoc Tukey test between groups. Enamel surface was photographed by digital microscope.
All intervention methods used in the current study significantly increased microhardness values of demineralized enamel (P < 0.001). Little improvement of enamel appearance was observed in all groups meanwhile using CO laser on demineralized enamel directly led to signs of white and black dots affecting the appearance of enamel surface.
The most effective intervention regarding microhardness was group 2 followed by group 3, group 4 and group 1. Coating the enamel surface with 3M Vanish™ before CO laser irradiation acted as a protective layer from the undesirable effects of laser on the teeth with increasing enamel microhardness values more than using Vanish alone. So the promising intervention method regarding both microhardness and appearance was group 4.
本体外研究旨在通过显微硬度测试和数字显微镜评估含氟牙膏加磷酸三钙（TCP）在有或无CO激光照射情况下对脱矿釉质处理的效果。
80颗完整拔除的人前磨牙随机分为4组（每组20颗）。每组牙齿均置于脱矿溶液中以形成白斑病变。第1组用3M防蛀修复牙膏（Vanish™）处理。第2组接受CO激光照射。第3组先接受CO激光照射，然后用3M防蛀修复牙膏处理。第4组先用3M防蛀修复牙膏处理，然后接受CO激光照射。将牙齿浸泡在人工唾液中。在基线脱矿前（M1作为对照）、脱矿后（M2）以及处理后（M3）测量每颗牙齿的表面显微硬度。使用单因素方差分析对各组间的显微硬度值进行比较，显著性水平为（0.05），随后进行组间多重比较的事后Tukey检验。用数字显微镜拍摄釉质表面照片。
本研究中使用的所有干预方法均显著提高了脱矿釉质的显微硬度值（P < 0.001）。所有组釉质外观改善均不明显，同时直接对脱矿釉质使用CO激光导致出现白色和黑色斑点，影响釉质表面外观。
关于显微硬度，最有效的干预组是第2组，其次是第3组、第4组和第1组。在CO激光照射前用3M防蛀修复牙膏覆盖釉质表面，可作为保护层，防止激光对牙齿产生不良影响，且釉质显微硬度值的增加幅度大于单独使用防蛀修复牙膏。因此，在显微硬度和外观方面最有前景的干预方法是第4组。
