Photobiomodulation Therapy Effects on Guided Bone Regeneration Materials: a Pilot Study

Objectives: Photobiomodulation therapy (PBMT) has been shown to encourage cell proliferation and osteogenic differentiation of mesenchymal cells. Similarly, guided bone regeneration membranes used as scaffolds for bone tissue engineering can stimulate proliferation and mineralization of dental pulp derived mesenchymal cells. This study assessed the role of PBMT in an in-vitro model using bovine pericardium membranes (BPM) and murine derived dental pulp cells (OD-21).
Methods: OD-21 were seeded in roughly 4 x 10⁴ per 70 μL onto BPM (CopiOs, Zimmer Biomet, Warsaw, IN, USA) that were glued down with a low toxicity silicone adhesive onto a 24-well tissue culture plate and cultured using non-odontogenic basal growth medium. PBMT was conducted 48-hours post seeding using a diode 660nm low-level laser probe (THOR Photomedicine Inc, Hampstead, MD), in continuous mode with an energy density of 1J/cm² and total cumulative energy of 4.6J/well. Treatment and control groups were maintained under the same conditions (humidity and temperature). Cell proliferation and mineralization were measured at day 7 using AlamarBlue and Alizarin red staining, respectively. T-test, (α=0.05) was used to test for significant differences.
Results: There was a significant increase in cellular proliferation and mineralization on cells cultured onto the BPM and treated with PBMT compared to cells cultured on BPM alone (p<0.0001 and p<0.008, respectively).
Conclusions: Considering the limitations of this in-vitro pilot study, this data suggests that PBMT with 660 nm laser wavelength may enhance guided bone regeneration procedures. Further studies will evaluate the long-term effect of PBMT on OD-21 proliferation and mineralization when used combined with guided bone regeneration BPM.