Evaluation of non-surgical laser (LLLT) on the growth and cell adherence of fibroblasts cultivated on titanium implants: in vitro study

Abstract

Lasertherapy has been cur- rently used due to its therapeuti- cal and biomodulatory effects. It is known that lasertherapy may im- prove the healing and integration quality between dental implants and bone and periodontal tissues. However, is still uncertain if it is possible to induce laser cell biosti- mulation in the presence of den- tal titanium implants. The aim of the present study was to examine adherence, proliferation and gro- wth on a titanium surface of NIH- 3T3 fibroblasts cell line submitted to diode laser irradiation (l=685 nm). Two experimental groups containing four cultures each one were cultured on titanium discs and placed in a 24 well pla- te. Cells were cultured in DMEM medium supplemented with 10% of fetal calf serum (BFS). After acquiring culture, one group was irradiated three times (24, 48 e 72 hours) with a diode laser 7 mW, l=685 nm, Æ~0,60 mm) with an energy density of 0,8 J.cm-2 per session. The other group was maintained without any treat- ment. Control group was grown under the same conditions, in the absence of titanium and was not irradiated either. Propidium iodi- de staining and hemocytometer chamber were used to evaluate cell adherence and cell growth respectively. According to average cell counts, it was possible to de- termine that cells reached an ac- tive and significant proliferation stage 72 (p=0,010) and 96 hours (p=0,007) after cell cultivation and were able to adhere and grow on titanium surface. Therefore our data indicates that laserthe- rapy, under conditions described above, may positively affect in vi- tro cell proliferation and probably may play important role on den- tal implants and periodontal tis- sues integration. Key words: biostimulation, laser- therapy, cell proliferation, dental implants.