Dosage Effects of an 810 nm Diode Laser on the Proliferation and Growth Factor Expression of Human Gingival Fibroblasts

Osteoinductive activity of photobiomodulation in an organotypic bone model

Photobiomodulation (PBM) is a technique that harnesses non-ionizing light at specific wavelengths, triggering the modulation of metabolic pathways, engendering favourable biological outcomes that reduce inflammation and foster enhanced tissue healing and regeneration. PBM holds significant promise for bone tissue applications due to its non-invasive nature and ability to stimulate cellular activity and vascularization within the healing framework. Notwithstanding, the impact of PBM on bone functionality remains largely undisclosed, particularly in the absence of influencing factors such as pathologies or regenerative therapies. This study aims to investigate the potential effects of PBM using red (660 nm) (RED) and near-infrared (808 nm) (NIR) wavelengths within an ex vivo bone culture system - the organotypic embryonic chicken femur model. A continuous irradiation mode was used, administering a total energy dose of 1.0 J, at an intensity of 100 mW for 10 s, which was repeated four times over the course of the 11-day culture period. The primary focus is on characterizing the expression of pivotal osteoblastic genes, the maturation and deposition of collagen, and the formation of bone mineral. Exposing femora to both RED and NIR wavelengths led to a notable increase in the expression of osteochondrogenic transcription factors (i.e., SOX9 and RUNX2), correlating with enhanced mineralization. Notably, NIR irradiation further elevated the expression of bone matrix-related genes and fostered enhanced deposition and maturation of fibrillar collagen. This study demonstrates that PBM has the potential to enhance osteogenic functionality within a translational organotypic bone culture system, with the NIR wavelength showing remarkable capabilities in augmenting the formation and maturation of the collagenous matrix.

The use of low level laser therapy in conjunction with diode laser-assisted and conventional vestibuloplasty: Comparison of wound healing and vestibular depth gain

BACKGROUND

The aim of this study is to compare wound healing and vestibular depth gain in individuals undergoing vestibule deepening surgery using diode laser and conventional technique and to further investigate the possible wound healing effect of low-level laser therapy (LLLT).

MATERIAL AND METHODS

52 systemically healthy individuals with insufficient vestibular depth in the region of teeth 33-43 in the lower jaw were included. Following nonsurgical periodontal treatment, patients were divided into four groups as follows: a) diode laser (L); b) diode laser + LLLT; c) conventional surgery and d) conventional surgery + LLLT. Vestibular depth and horizontal wound size measurements of the individuals were recorded using digital calipers. Reepithelization was evaluated via an image analysis program.

RESULTS

Vestibular depth measurements were found to be higher in the conventional surgery groups compared to that of diode laser groups after the operation, while the results were not statistically different between groups (p >0.05). Reepithelization area did not differ between groups in the evaluated time periods (p >0,05). On the other hand, horizontal wound shrinkage was significantly higher in the conventional surgery group than that of diode laser.

CONCLUSIONS

Within the limits of this study, both methods yielded in vestibule depth gain. On the other hand, LLLT did not have an additional positive effect on mucosal wound healing. As a clinical relevance, the results are valuable for clinicians in terms of showing that suturing of the mucosal flap formed following vestibule deepening should not be necessary in laser assisted surgery for attaining more vestibule depth.