Evaluating the impact of soft tissue flaps on red and near-infrared light transmission in porcine cortical bone: a preliminary study for dental applications

Photobiomodulation (PBM) therapy utilizes red and near-infrared light (600 to 1,100nm). This therapy is gaining prominence as a non-invasive treatment modality in dentistry. Researchers have noted that the effect of tissue structure on light transmission remains underexplored. They emphasize the need for further investigation in the context of clinical dentistry. This study aims to investigate the impact of a soft tissue flap on the transmission of 660nm and 810nm light sources through cortical bone, thereby providing insights for future research applications in periodontal surgery. This study utilized the porcine mandibular cadaver bone model to simulate the effects of light transmission in human cortical bone. Researchers placed soft tissue flaps over a cortical bone sample and applied light from FDA-approved clinical PBM devices in both 660nm and 810nm. An isotropic detector measured the light with the resulting fluence rate calculated in mW/cm². Preliminary data indicated that the soft tissue flap significantly reduces light transmission at both wavelengths, suggesting that the depth of light penetration and tissue absorption characteristics differ between red and near-infrared light. In conclusion, this study highlights the necessity of carefully considering tissue structures in PBM applications, especially in clinical dentistry, where accurate dosimetry is critical. Future research should focus on optimizing PBM device parameters to ensure sufficient light transmission through soft and hard tissues for effective therapeutic outcomes.