Effects of low intensity laser in in vitro bacterial culture and in vivo infected wounds

OBJECTIVE: to compare the effects of low intensity laser therapy on in vitro bacterial growth and in vivo in infected wounds, and to analyze the effectiveness of the AsGa Laser technology in in vivo wound infections. METHODS: in vitro: Staphylococcus aureus were incubated on blood agar plates, half of them being irradiated with 904 nm wavelength laser and dose of 3J/cm2 daily for seven days. In vivo: 32 male Wistar rats were divided into control group (uninfected) and Experimental Group (Infected). Half of the animals had their wounds irradiated. RESULTS: in vitro: there was no statistically significant variation between the experimental groups as for the source plates and the derived ones (p>0.05). In vivo: there was a significant increase in the deposition of type I and III collagen in the wounds of the infected and irradiated animals when assessed on the fourth day of the experiment (p=0.034). CONCLUSION: low-intensity Laser Therapy applied with a wavelength of 904nm and dose 3J/cm2 did not alter the in vitro growth of S. aureus in experimental groups; in vivo, however, it showed significant increase in the deposition of type I and III collagen in the wound of infected and irradiated animals on the fourth day of the experiment.

研究目的：比较低强度激光疗法对体外（in vitro）细菌生长及体内（in vivo）感染创面的影响，并分析砷化镓（AsGa）激光技术在体内创面感染模型中的应用效果。
研究方法：
体外实验：将金黄色葡萄球菌（Staphylococcus aureus）接种于血琼脂平板，其中半数每日接受波长904nm、剂量3J/cm²的激光照射，连续照射7天。
体内实验：选取32只雄性Wistar大鼠，分为对照组（未感染创面组）与实验组（感染创面组），其中半数大鼠的创面接受激光照射处理。
研究结果：
体外实验：实验组与对照组的初始平板及衍生培养平板的细菌生长水平无统计学显著差异（p>0.05）。
体内实验：在实验第4天进行评估时，感染且接受激光照射的大鼠创面中，I型与III型胶原蛋白的沉积量显著升高（p=0.034）。
研究结论：采用波长904nm、剂量3J/cm²的低强度激光疗法，未对体外实验中金黄色葡萄球菌的生长产生显著影响；但在体内实验中，实验第4天时，感染且接受激光照射的大鼠创面的I型与III型胶原蛋白沉积量显著升高。