Recalcification of Enamel Due to Laser Ablation

从亚微米级磷酸三钙（TCP）中提取TCP浆料，制备出几十μm厚的TCP片材。分别用准分子激光、调Q YAG激光和CO_2激光对脱钙牙釉质尖进行光固化处理。我们研究了激光烧蚀对牙釉质钙化的影响。按照常规方法，我们制作了如下样品：将一颗拔除的恒牙去除约200 μm的表面，将其抛光，将其在0.1 M-乳酸缓冲溶液（0.3 mM -HAp，pH 4.5）中脱钙4小时。两个牙釉质标本的同一牙齿。其中一个样品在浆料或片材上进行辐照（2个反应组），另一个样品在浆料和片材上进行单独辐照（对照组）。部分标本用人工唾液浸泡4周，观察其钙化情况。在制浆过程中，TCP（平均粒径为0.41 μm） 关于我们 用纯化水稀释至10-20%。将10%磷酸三钙浆液、琼脂粉、马铃薯淀粉与纯净水混合，在85℃下加热溶解。然后将适量的溶液倒入塑料膜（厚度为30-60 μm）中，然后放置，干燥并切成约5 mm见方。作为TCP片材的粘合剂，使用5%CMC、0. 3 mM-HAp溶液和75%HAp浆料。各种辐照条件; 248 nm（KrF）准分子激光，355 nm（基本波长1, 064 nm的三次谐波产生）和10，用波长600 nm的CO_2激光，以70-150 mJ/cm ~ 2、0.8-1.0 W/lsec的能量，照射2000次，在70-100 mJ/cm ~ 2的能量范围内，激光烧蚀牙釉质表面准分子激光/YAG激光，0.8W/lsec。激光烧蚀能更有效地提高TCP在脱钙牙釉质表面的粘附效果。在CO_2激光照射下，浆料和板材表面形成激光烧蚀羽流，人工唾液也能促进浆料和板材的再钙化。少

TCP slurry was extracted from tertiary calcium phosphate (TCP) of submicron particles, by which TCP sheets (dozens of μm in thickness) were made. The decalified enamel tip coated with slurry and sheets were irradiated by excimer laser, Q switch YAG laser and CO_2 Laser, respectively. We studied the effect of laser ablation on recalcification of enamel.According to the conventional method, we made specimens as follows ; an extracted permanent tooth that approximately 200 μm of the surface was removed was polished, which was decalcified for 4 hours into a 0.1 M-lactic acid buffer solution (0.3 mM -HAp, pH 4.5). Two enamel specimen of the same tooth were employed. One specimen was irradiated on slurry or sheets (2 reacted groups), and the other one was then treated by single slurry and sheets without irradiation (control group). Some specimens were immersed with artificial saliva for 4 weeks, whose recalcification was observed. In making slurry, TCP (a mean granular diameter of 0.41 μm) w … More as prepared to 10-20% with purified water. In making sheets, 10% TCP slurry, agar powder and potato starch mixed with purified water was heated at 85℃, and dissolved. An adequate amount of the solution was then poured into a plastic schale (30-60 μm in thickness), was then left, dried and cut to approximately 5 mm square. As adhesive agents for TCP sheets, 5% CMC, a 0.3 mM-HAp solution and 75% HAp slurry were employed. Each condition of irradiation ; 248 nm (KrF) of excimer laser, 355 nm (the 3rd harmonic generation of basic wavelength 1,064 nm) of Q switch YAG laser and 10,600 nm of CO_2 laser at 2000 shots of 70-150 mJ/cm^2 and 0.8-1.0 W/lsec were irradiated.Laser ablation occurred on slurry or sheets of enamel tip at 70-100 mJ/cm^2 of excimer laser/YAG laser and 0.8 W/lsec of CO_2 laser. The adherent effect of TCP in slurry or sheets for decalcified enamel surface was more strongly enhanced by laser ablation. In CO_2 laser irradiation, laser ablation plume was formed on slurry and sheets.Recalcification of adherent slurry and sheets was also more advanced by artificial saliva. Less