A pilot study of laser energy transmission through bone and gingiva.

BACKGROUND: The use of low-level laser therapy is growing in the field of dentistry especially in orthodontics to speed up tooth movement and in implantology to aid osseointegration. In these dental applications, the laser energy needs to penetrate through the periodontium to the target site to stimulate photobiomodulation. The percentage of energy loss when laser is transmitted through the periodontium has not been previously studied. With the use of an 808-nanometer diode laser, the aim was to investigate the percentage loss of laser energy when transmitted through the periodontium to the extraction socket.

METHODS: The percentage energy loss of an 808-nm diode laser through the periodontium was measured in 27 tooth sockets by using a specifically designed photodiode ammeter.

RESULTS: For each millimeter of increased bone thickness there was 6.81% reduction in laser energy (95% confidence interval, 5.02% to 8.60%). The gingival thickness had no statistically significant effect on energy penetration.

CONCLUSION: Energy penetration depends markedly on bone thickness and is independent of gingival thickness.

PRACTICAL IMPLICATIONS: To the best of the authors' knowledge, this study is one of the first to investigate laser penetration through the periodontium. Evidence from this study showed that laser energy penetration through the periodontium is markedly affected by bone thickness but less so by gingival thickness. Clinicians need to be aware of the biological factors that could affect laser energy penetration to the target site and adjust their laser dosages accordingly. These findings may guide dental practitioners in selecting the appropriate laser dosage parameters for low-level laser therapy.