Department of Periodontology, Faculty of Dentistry, Selçuk University, Konya, Turkey.
J Periodontol. 2010 Aug;81(8):1216-25. doi: 10.1902/jop.2010.090715.
This study investigates the effects of erbium, chromium:yttrium-scandium-gallium-garnet (Er,Cr:YSGG) laser irradiation and hand instrumentation on the attachment of periodontal ligament (PDL) fibroblasts to periodontally involved root surfaces.
Twenty-four single-rooted periodontally involved human teeth (test groups), and six healthy premolar teeth extracted for orthodontic reasons (control group) were included in this study. A total of 45 root slices were obtained from all selected teeth and assigned to the following five groups: 1) untreated healthy group (+control); 2) untreated periodontally diseased group (-control); 3) hand instrumentation group (scaled Gracey); 4) laser I, Er,Cr:YSGG laser irradiation setting-I (short pulse); and 5) laser II, Er,Cr:YSGG laser irradiation setting-II (long pulse). All of the root slices were autoclaved in phosphate buffered saline and slices were placed onto cell culture inserts. PDL fibroblasts were placed at the density of 80,000 cells on the root plate (5 x 6 mm) and incubated for 48 hours and transferred to 24-well plates. The attachment PDL fibroblasts on the root plates were observed using confocal microscopy (at 12 hours and on days 3 and 7) and scanning electron microscopy (at 12 hours and day 3). 3-(4,5-dimethyl-thiazol-2-yl)-2,5-diphenyl-tetrazolium bromide assay was performed on day 5 for PDL fibroblast survival.
3-(4,5-dimethyl-thiazol-2-yl)-2,5-diphenyl-tetrazolium bromide assay shows that whereas laser-treated specimens showed a significantly higher cell density, the Gracey-treated group showed a lower cell density compared to the positive control group (P <0.05). Based on confocal microscopy, apparent reduction was observed in the attachment of PDL cells to the periodontally diseased root surfaces. In the laser and Gracey groups, cells looked well-oriented to the root surfaces. Laser-treated groups provided suitable environment for cell adhesion and growth. Laser I treatment was more favorable for the attachment of PDL compared to scaled Gracey, laser II, and even healthy root surfaces.
The results of the study indicate that short-pulse laser setup (laser I) looks more promising regarding the attachment, spreading, and orientation of PDL cells.
本研究旨在探讨铒铬石榴石（Er,Cr:YSGG）激光照射和手动器械对牙周病受累牙根表面牙周膜（PDL）成纤维细胞附着的影响。
本研究纳入 24 颗因牙周病而拔除的单根人恒牙（实验组）和 6 颗因正畸原因拔除的健康前磨牙（对照组）。从所有选定的牙齿中获得了总共 45 个牙根切片，并将其分为以下五组：1）未处理的健康组（+对照）；2）未处理的牙周病组（-对照）；3）手动器械组（Gracey 刮治）；4）激光 I，Er,Cr:YSGG 激光照射设置-I（短脉冲）；和 5）激光 II，Er,Cr:YSGG 激光照射设置-II（长脉冲）。所有牙根切片均在磷酸盐缓冲盐水（PBS）中进行高压灭菌，并将切片置于细胞培养插入物上。将牙周膜成纤维细胞以 80,000 个细胞/平方厘米的密度放置在牙根板（5 x 6 毫米）上，并孵育 48 小时，然后转移到 24 孔板中。在 12 小时、第 3 天和第 7 天使用共聚焦显微镜观察牙根板上附着的牙周膜成纤维细胞，并在 12 小时和第 3 天使用扫描电子显微镜观察。在第 5 天进行 3-(4,5-二甲基噻唑-2-基)-2,5-二苯基四唑溴盐（MTT）比色法测定牙周膜成纤维细胞的存活率。
MTT 比色法显示，与激光处理组相比，Gracey 处理组的细胞密度明显较低，而激光处理组的细胞密度明显高于阳性对照组（P <0.05）。基于共聚焦显微镜，牙周病受累牙根表面牙周膜细胞的附着明显减少。在激光和 Gracey 组中，细胞看起来很好地定向到牙根表面。激光处理组为细胞黏附和生长提供了适宜的环境。与 Gracey 刮治、激光 II 甚至健康牙根表面相比，激光 I 处理更有利于牙周膜成纤维细胞的附着。
研究结果表明，短脉冲激光设置（激光 I）在牙周膜细胞的附着、铺展和定向方面更有前景。
