School of Dentistry, Shenzhen University Health Science Center, Shenzhen, China.
Faculty of Dentistry, The University of Hong Kong, Hong Kong, China.
Photobiomodul Photomed Laser Surg. 2020 May;38(5):295-300. doi: 10.1089/photob.2019.4720.
To investigate the caries prevention effect of silver diamine fluoride (SDF) with a carbon dioxide (CO) laser (λ = 10,600 nm) on dentin. Human dentin slices ( = 10) were prepared and allocated to the following treatments: Group 1 (SDF)-slices received an SDF application. Group 2 (laser)-slices were irradiated with a CO laser. Group 3 (laser + SDF)-slices were irradiated with a CO laser, followed by an SDF application. Group 4 (negative control)-slices had no treatment. All of the slices were subjected to pH cycling for cariogenic challenge. Lesion depth, nanohardness, and chemical and morphological changes were assessed by microcomputed tomography (micro-CT), nanoindentation, and scanning electron microscopy (SEM) with energy dispersive X-ray spectroscopy (EDS), respectively. micro-CT determined lesion depths for groups 1-4 were 27 ± 6, 138 ± 32, 17 ± 5, and 182 ± 49 μm, respectively ( < 0.001; group 3 < group 1 < groups 2 and 4). The nanohardness values for groups 1-4 were 456 ± 109, 288 ± 5, 444 ± 142, and 258 ± 76 MPa, respectively ( = 0.003; groups 2 and 4 < groups 1 and 3). EDS determined that the calcium-to-phosphorus molar ratio for groups 1-4 were 1.26 ± 0.12, 1.07 ± 0.19, 1.37 ± 0.08, and 0.80 ± 0.17, respectively ( < 0.001; group 4 < group 2 < groups 1 and 3). SEM evidenced no ablation or cracking on the lased dentin surfaces. The treated dentin showed a relatively more intact and smoother surface morphology compared with the untreated dentin. SDF can reduce dentin demineralization against cariogenic challenge, and the caries preventive effect of SDF is further enhanced through CO laser irradiation.
为了研究银胺氟化物（SDF）与二氧化碳（CO）激光（λ=10600nm）联合应用于牙本质的防龋效果。制备了 10 个人类牙本质切片，并将其分配到以下处理组：组 1（SDF）- 切片接受 SDF 处理。组 2（激光）- 切片用 CO 激光照射。组 3（激光+SDF）- 切片先用 CO 激光照射，然后再用 SDF 处理。组 4（阴性对照）- 切片无任何处理。所有切片均进行 pH 循环以进行致龋挑战。使用微计算机断层扫描（micro-CT）、纳米压痕和扫描电子显微镜（SEM）分别结合能量色散 X 射线光谱（EDS）评估病变深度、纳米硬度以及化学和形态变化。micro-CT 确定各组病变深度分别为 27±6μm、138±32μm、17±5μm 和 182±49μm（<0.001；组 3<组 1<组 2 和组 4）。各组纳米硬度值分别为 456±109MPa、288±5MPa、444±142MPa 和 258±76MPa（=0.003；组 2 和组 4<组 1 和组 3）。EDS 确定各组钙磷摩尔比分别为 1.26±0.12、1.07±0.19、1.37±0.08 和 0.80±0.17（<0.001；组 4<组 2<组 1 和组 3）。SEM 显示激光处理后的牙本质表面无烧蚀或裂纹。与未经处理的牙本质相比，处理后的牙本质表面形态相对更完整、更光滑。SDF 可减少牙本质脱矿，抵抗致龋挑战，CO 激光照射可进一步增强 SDF 的防龋效果。
