Leicester School of Pharmacy, De Montfort University, Leicester LE1 9BH, UK.
Laser Research Center, Dentistry Research Institute, Tehran University of Medical Sciences, Tehran, Iran.
Curr Stem Cell Res Ther. 2024;19(4):544-558. doi: 10.2174/1574888X17666220527090321.
Stem cell therapy has been considered to play a paramount role in the treatment modalities available for regenerative dentistry. The established beneficial effects of photobiomodulation (PBM) at the cellular level have led to the combined use of these two factors (PBM and stem cells). The main goal of this study was firstly to critically appraise the effects of PBM on periodontal ligament stem cells (PDLSCs), and secondly to explore the most effective PBM protocols applied.
Pubmed, Cochrane, Scopus, Science Direct, and Google Scholar search engines were used to identify experimental studies in which PBM was applied to cultured PDLSCs. After applying specific keywords, additional filters, and inclusion/exclusion criteria, a preliminary number of 245 articles were narrowed down to 11 in which lasers and LEDs were used within the 630 - 1064 nm wavelength range. Selected articles were further assessed by three independent reviewers for strict compliance with PRISMA guidelines, and a modified Cochrane risk of bias to determine eligibility.
The dataset analysed was extracted from the studies with sufficient and clearly presented PBM protocols. Simple univariate regression analysis was performed to explore the significance of contributions of potential quantitative predictor variables toward study outcomes, and a one-way ANOVA model was employed for testing differences between the laser or LED sources of the treatments. The significance level for testing was set at α = 0.05.
The proliferation rate, osteogenic differentiation, and expression of different indicative genes for osteogenesis and inflammation suppression were found to be positively affected by the application of various types of lasers and LEDs. With regard to the PBM protocol, only the wavelength variable appeared to affect the treatment outcome; indeed, the 940 nm wavelength parameter was found not to exert a favourable effect.
Photobiomodulation can enhance the stemness and differentiation capacities of periodontal ligament stem cells. Therefore, for PBM protocols, there remains no consensus amongst the scientific community. Statistical analyses performed here indicated that the employment of a near-infrared (NIR) wavelength of 940 nm may not yield a significant favourable outcome, although those within the 630 - 830 nm range did so. Concerning the fluence, it should not exceed 8 J/cm when therapy is applied by LED devices, and 4 J/cm when applied by lasers, respectively.
干细胞疗法被认为在再生牙科的治疗方法中起着至关重要的作用。光生物调节（PBM）在细胞水平上的既定有益作用促使这两种因素（PBM 和干细胞）的联合使用。本研究的主要目的首先是批判性地评估 PBM 对牙周韧带干细胞（PDLSCs）的影响，其次是探索应用的最有效 PBM 方案。
使用 Pubmed、Cochrane、Scopus、Science Direct 和 Google Scholar 搜索引擎来识别应用 PBM 于培养的 PDLSCs 的实验性研究。在应用特定的关键词、附加过滤器和纳入/排除标准后，初步有 245 篇文章被缩小到 11 篇，其中使用了激光和发光二极管，波长范围在 630-1064nm 之间。选择的文章由三名独立评审员进一步评估，以严格遵守 PRISMA 指南，并采用改良的 Cochrane 偏倚风险来确定合格性。
从具有足够和明确呈现的 PBM 方案的研究中提取分析数据集。进行简单的单变量回归分析，以探索潜在定量预测变量对研究结果的显著贡献，并且采用单向方差分析模型来测试治疗中激光或发光二极管源之间的差异。测试的显著性水平设定为α=0.05。
发现各种类型的激光和发光二极管的应用可正向影响增殖率、成骨分化以及成骨和炎症抑制的不同指示基因的表达。就 PBM 方案而言，只有波长变量似乎影响治疗结果；实际上，发现 940nm 波长参数没有产生有利影响。
光生物调节可以增强牙周韧带干细胞的干性和分化能力。因此，对于 PBM 方案，科学界尚未达成共识。这里进行的统计分析表明，在近红外（NIR）波长 940nm 下的应用可能不会产生显著有利的结果，尽管在 630-830nm 范围内是这样的。关于剂量，当应用于 LED 设备时，不应超过 8J/cm，当应用于激光时，不应超过 4J/cm。
