Pelino J E, Mello J B, Eduardo C P, Jorge A O
Department of Restorative Dentistry, UNESP, São José dos Campos, Brazil.
J Clin Laser Med Surg. 1999;17(4):171-7. doi: 10.1089/clm.1999.17.171.
The Nd:YAG laser irradiation of dental enamel was evaluated in enamel demineralization experiments in a Streptococcus mutans culture media.
Previous studies had shown that a continuous wave Nd:YAG laser at an energy of approximately 67 mJ may induce an increased acid resistance in human dental enamel when exposed to severe demineralization conditions.
Enamel windows of 3 x 4 cm in the buccal surface were irradiated with a continuous wave Nd:YAG laser at a wavelength of 1,064 microns using energy densities of from 83.75 to 187.50 J/cm2. Enamel windows of 3 x 4 cm on the lingual surface served as control (without the laser irradiation). The enamel windows were then exposed to a Streptococcus mutans culture media at a temperature of 37 degrees C for 15 and 21 days. The laser effects and demineralization were examined both by optical microscopy and scanning electron microscopy (SEM).
A comparison between the lased and the unlased windows of enamel showed fusion and recrystalization of the enamel and increased acid-resistance in all groups irradiated with the Nd:YAG laser. On the other hand, the 3 x 4 delimited enamel surfaces from the control group (not irradiated with the Nd:YAG laser) showed 100% demineralization.
These findings are consistent with the finding that laser irradiation of dental results in significant reduction of the effective solubility of enamel mineral.
在变形链球菌培养基的牙釉质脱矿实验中评估钕钇铝石榴石（Nd:YAG）激光对牙釉质的照射效果。
先前的研究表明，能量约为67 mJ的连续波Nd:YAG激光在暴露于严重脱矿条件下时，可能会增强人类牙釉质的耐酸性。
使用能量密度为83.75至187.50 J/cm²的波长为1064微米的连续波Nd:YAG激光照射颊面3×4厘米的牙釉质窗。舌面3×4厘米的牙釉质窗作为对照（未进行激光照射）。然后将牙釉质窗置于37摄氏度的变形链球菌培养基中15天和21天。通过光学显微镜和扫描电子显微镜（SEM）检查激光效果和脱矿情况。
牙釉质经激光照射和未经激光照射的窗口对比显示，在所有接受Nd:YAG激光照射的组中，牙釉质均发生融合和再结晶，且耐酸性增强。另一方面，对照组（未接受Nd:YAG激光照射）的3×4划定牙釉质表面显示100%脱矿。
这些发现与以下发现一致，即对牙齿进行激光照射会显著降低牙釉质矿物质的有效溶解度。
