Impact of Er: YAG Laser Irradiation on the Proliferation of Human Periodontal Ligament Fibroblasts

Abstract The key to success of replantation of totally avulsed teeth is periodontal ligament activity. Improving the activity of periodontal ligament cell is beneficial to the success rate of tooth replantation. Objectives: To observe the changes in proliferation of human periodontal ligament fibroblasts cultured in vitro after Er:YAG laser irradiation. Methods: Conventional immumohistochemical staining was performed on human periodontal ligament fibroblasts cultured in vitro which was obtained from teeth root surface to identify the cell source. The fifth generation of human periodontal ligament fibroblasts collected were randomly divided into 5 groups, with group A as the control group receiving no laser irradiation, and experimental groups receiving different energies of Er:YAG laser radiation, respectively. The parameters were 50mJ, 10Hz and 1s radiation in B group; 100mJ, 10Hz and 1s radiation in C group; 150mJ, 10Hz and 1s radiation in D group; 200mJ, 10Hz and 1s radiation in E group. Cell growth was detected by CCK-8 method on Day 1, 3, 5, 7 and 9, respectively, and the changes in cell proliferation were analyzed. Result: The cell proliferation rates in experimental groups were higher than that in the control group, and there were statistical differences. Conclusion: Er:YAG laser irradiation with low energy and short time can promote the proliferation of periodontal ligament fibroblasts. Further studies are needed to determine whether the success rate of tooth replantation can be improved.