Pereira Aymann Nassif, Eduardo Carlos de Paula, Matson Edmir, Marques Márcia Martins
Department of Stomatology, School of Dentistry, University of São Paulo-SP, Brazil 05508-900.
Lasers Surg Med. 2002;31(4):263-7. doi: 10.1002/lsm.10107.
In dentistry, low-power lasers have been used in the treatment of dentin hypersensitivity, gingivitis, periodontitis, and different forms of oral ulcers. This in vitro study focuses on the biostimulation of NIH-3T3 fibroblasts by a low-power Ga-As-pulsed laser.
STUDY DESIGN/MATERIALS AND METHODS: We have studied cell growth and procollagen synthesis of cultured fibroblasts submitted to low-power laser irradiation with energy densities varying from 3 to 5 J/cm(2) over a period of 1-6 days. The light source was a 120 mW Ga-As diode laser (lambda = 904 nm). Growth curves and procollagen immunoprecipitation were obtained.
Irradiation of 3 and 4 J/cm(2) increased the cell numbers about threefold to sixfold comparing to control cultures. However, this effect was restricted to a small range of energy densities since 5 J/cm(2) had no effect on cell growth. The energy density of 3 J/cm(2) remarkably increased cell growth, with no effect on procollagen synthesis, as demonstrated by the immunoprecipitation analysis.
Our results showed that a particular laser irradiation stimulates fibroblast proliferation, without impairing procollagen synthesis.
在牙科领域，低功率激光已被用于治疗牙本质过敏、牙龈炎、牙周炎以及不同类型的口腔溃疡。这项体外研究聚焦于低功率砷化镓脉冲激光对NIH-3T3成纤维细胞的生物刺激作用。
研究设计/材料与方法：我们研究了在1至6天的时间内，能量密度在3至5 J/cm²范围内的低功率激光照射对培养的成纤维细胞生长和前胶原合成的影响。光源为120 mW的砷化镓二极管激光（波长 = 904 nm）。获得了生长曲线和前胶原免疫沉淀结果。
与对照培养物相比，3 J/cm²和4 J/cm²的照射使细胞数量增加了约三倍至六倍。然而，这种效应仅限于小范围的能量密度，因为5 J/cm²对细胞生长没有影响。免疫沉淀分析表明，3 J/cm²的能量密度显著促进细胞生长，但对前胶原合成没有影响。
我们的结果表明，特定的激光照射可刺激成纤维细胞增殖，而不损害前胶原合成。
