Low Level Laser Therapy With an 810-nm Diode Laser Affects the Proliferation and Differentiation of Premature Osteoblasts and Human Gingival Fibroblasts In Vitro

Introduction: Photomodulation is a promising strategy for optimizing tissue healing, but its photomodulatory effects on the synergistic cellular metabolism of gingival and bony tissues remain largely unknown. The aim of the present study was to evaluate the photomodulatory effects of a diode laser (810 nm) on osteoblasts, HGFs and their co-cultures in vitro. Methods: Primary cultures of HGFs, cultures of immature osteoblastic cells (MG63) and their cocultures were irradiated with a diode laser (810 nm), 15 J/cm2. Cell cultures were examined for cellular proliferation (MTT assay), viability (FDA/PI staining) after 24, 48 and 72 hours and cell differentiation (qPCR of collagen type 1a - COL1a and alkaline phosphatase expressions - ALP) after 7 days. Results: Photomodulation with an 810-nm diode laser increased cell proliferation at all time points. COL1a gene expression increased both in HGF and co-cultures. ALP expression was up-regulated in osteoblastic cultures, but co-cultures with fibroblasts negated this response. Conclusion: The 810-nm diode laser positively affected cell proliferation and viability in all experimental groups. The statistically significant increased COL1a gene expression at 7 days after irradiation both in the irradiated HGF and co-cultures suggests that low-level laser therapy (LLLT) stimulated extracellular matrix (ECM) formation signaling in both cell types. © 2021. All Rights Reserved

Long-term biological complications of dental implants placed either in pristine or in augmented sites: A systematic review and meta-analysis.

AIM To investigate and compare the prevalence of biological complications and failure of implants placed in pristine vs. augmented sites after a mean observation period of at least 10 years. MATERIALS AND METHODS The focused question "In patients with osseointegrated dental implants, are there differences in biological complications and implant failure at implants placed in pristine vs. augmented sites?" was addressed using the Population, Exposure, Comparison and Outcome criteria. Electronic and manual searches supplemented by the screening of the grey literature were carried out. A case definition of peri-implant mucositis and peri-implantitis had to be specified. The binary random-effects method was chosen to conduct meta-analyses. Results are presented as Forest plots with weighted mean values and 95% confidence intervals (CI). The I statistic test was applied to quantify heterogeneity. The Newcastle-Ottawa Scale and the parameters provided in the Cochrane Center and CONSORT statement were used for quality assessment. The results are reported according to the PRISMA guidelines. RESULTS No randomized clinical trial (RCT) comparing the outcomes of implants placed in pristine vs. augmented sites was identified. Five case-series studies, one case-control study, one cross-sectional study and one RCT were eligible for qualitative and quantitative analyses. No statistically significant differences (p > .05) were observed between implants placed in pristine vs. augmented sites for any outcome variables both at patient and at implant levels, respectively. High heterogeneity concerning patient sampling, case definitions of biological complications and eligibility criteria was observed. CONCLUSION The studies included in the present systematic review did not directly address the focused questions. Hence, the outcomes of the meta-analysis should be interpreted with caution due to high variability with respect to study design