Liu Yuanyuan, Hsu Chin-Ying Stephen
Department of Preventive Dentistry, Faculty of Dentistry, National University of Singapore, 5 Lower Kent Ridge Road, Singapore 119074, Republic of Singapore.
J Dent. 2007 Mar;35(3):226-30. doi: 10.1016/j.jdent.2006.08.006. Epub 2006 Oct 11.
Preventive effects of lasers on enamel caries have been documented in the past few decades. However, its specific mechanism remains uncertain.
To evaluate the laser-induced change of enamel compositions, including carbonate and organic matters using Fourier-transform Raman spectroscopy (FT-Raman).
Twelve windows (1 mm x 1 mm), created on six defect-free primary incisors, were characterized by FT-Raman microscopy (1024 nm) before and after Er:YAG laser treatment (Fidelis) with 5.1 J/cm(2)-2 Hz-5s. To assess the statistical significance of laser effects, Raman peaks assigned to nu(1) phosphate, type-A/B carbonates, and organic matters were evaluated with the paired-samples t-test.
The standardized intensity of type B carbonate decreased significantly from 0.117 to 0.106 (p=0.029), whereas the standardized intensity of carbonate A remained unchanged (p=0.467). Related to organic matters, the standardized intensity of peaks at 2940 cm(-1) and in the ranges of 1200-1600 cm(-1) decreased significantly, with p=0.005 and p<0.001, respectively. Revealing enamel crystallinity, the bandwidth of nu(1) phosphate on lased surfaces appeared to be unaltered after laser treatment (p=0.477).
Laser treatment may provide caries-preventive effect on enamel through reduction of carbonate and modification of organic matters.
在过去几十年中，激光对牙釉质龋的预防作用已有文献记载。然而，其具体机制仍不确定。
使用傅里叶变换拉曼光谱（FT - 拉曼）评估激光诱导的牙釉质成分变化，包括碳酸盐和有机物。
在六颗无缺陷的乳切牙上制备十二个窗口（1毫米×1毫米），在使用波长为1024纳米的Er:YAG激光（Fidelis）以5.1焦耳/平方厘米 - 2赫兹 - 5秒进行处理前后，通过FT - 拉曼显微镜进行表征。为评估激光效应的统计学意义，使用配对样本t检验对归属于ν(1)磷酸盐、A/B型碳酸盐和有机物的拉曼峰进行评估。
B型碳酸盐的标准化强度从0.117显著降低至0.106（p = 0.029），而A型碳酸盐的标准化强度保持不变（p = 0.467）。关于有机物，2940厘米⁻¹处以及1200 - 1600厘米⁻¹范围内峰的标准化强度显著降低，p值分别为0.005和p < 0.001。在揭示牙釉质结晶度方面，激光处理后激光照射表面上ν(1)磷酸盐的带宽似乎未改变（p = 0.477）。
激光治疗可能通过减少碳酸盐和改变有机物对牙釉质提供防龋作用。
