Photobiomodulation: How Many Sessions and How Often?

Infrared laser therapy decreases systemic oxidative stress and inflammation in hypercholesterolemic mice with periodontitis

BACKGROUND

Near-infrared irradiation photobiomodulation (NIR-PBM) has been successfully used in periodontal treatment as an adjuvant tool to locally improve cell function and regeneration. Although the relationship between periodontitis and systemic disease constitutes an important aspect of periodontal clinical research, the systemic effects of NIR-PBM in periodontitis are not well known. In this study, we aimed to investigate the effects of NIR-PBM on systemic oxidative stress and inflammation in an apolipoprotein E (ApoE) knockout mouse model of periodontal disease (PD).

METHODS

We evaluated alveolar bone loss by measuring the distance from the cementoenamel junction (CEJ) to the alveolar bone crest (ABC), reactive oxygen species (ROS) production in blood cells, inflammatory activity, plasma cholesterol levels, and lipid peroxidation levels in three experimental groups: (1) ApoEC, control group without intervention; (2) ApoEP, first molar ligation-induced periodontitis for 4 weeks; and (3) ApoEP + PBM, exposed to 808 nm continuous wave, ø ~ 3 mm2, 100 mW, 60 s of NIR-PBM for 7 consecutive days after 4 weeks of periodontitis. At the end of the experimental protocols, ApoEP mice presented significantly increased alveolar bone loss, ROS production, inflammatory activity, plasma cholesterol, and lipid peroxidation levels compared to the ApoEC group (P < 0.05). NIR-PBM for 7 days in the ApoEP + PBM mice significantly decreased systemic ROS production, inflammatory response, plasma cholesterol, and lipid peroxidation levels, similar to those found in the ApoEC group (P > 0.05). However, it was not capable of preventing alveolar bone loss (P > 0.05 compared to ApoEP mice).

CONCLUSION

A 7-day treatment with NIR-PBM effectively reduces systemic oxidative stress and inflammatory parameters in hypercholesterolemic mice with PD. However, more studies with longer evaluation times are needed to confirm the systemic effects of locally applied NIR-PBM on PD associated with hypercholesterolemia.

Photobiomodulation self-treatment at home after rotator cuff arthroscopic repair accelerates improvement in pain, functionality, and quality of life: A double-blind, sham-controlled, randomized clinical trial

OBJECTIVE

To determine whether self-applied photobiomodulation (PBM) therapy at home, following rotator cuff arthroscopic surgery (RCAS) can accelerate improvement in patient-reported outcomes within the first 6 months postsurgery.

METHODS

This study was a prospective, double-blind, sham-controlled, randomized clinical trial (NCT04593342). Patients (n = 50, age 55 ± 7 years, male:female 29:21) who underwent primary RCAS were randomized to receive active (n = 22) or sham (n = 28) PBM devices (B-Cure Laser Pro, Erica B-Cure LASER Ltd., Haifa, Israel) in addition to standard care. Patients self-applied the treatments (808 nm, 15 min, 16.5 J/cm2 ) at home for 3 months postsurgery. Evaluations were conducted before the surgery (baseline) and at 1-3 and 6 months post-RCAS (FU-1M, FU-3M, FU-6M), and included Constant-Murley score (CMS), range of motion (ROM), subjective pain by visual analogue scale (VAS), disability by QuickDASH, and quality of life (QOL) by SF-12. The difference from baseline to follow-up (ΔFU), %patients achieving minimal clinical important difference (MCID), and patient acceptable symptom score (PASS) were calculated. Comparisons were conducted with superiority 2-sample t test and χ2 .

RESULTS

Baseline values were not significantly different between groups. Both groups had similar improvements in CMS and ROM. However, compared to Sham, PBM significantly accelerated subjective pain reduction at 3 and 6 months (VAS mean ± SD, PBM-vs-Sham: ΔFU-3M 32 ± 33 vs. 16 ± 27, p = 0.040; ΔFU-6M: 41 ± 36 vs. 23 ± 26, p = 0.038), with a significantly higher proportion of patients achieving MCID at 3 months (76% vs. 48%, p = 0.027) and PASS at 6 months (48% vs. 23%, p = 0.044). PBM also significantly accelerated improvement in functionality and QOL at 6 months (QuickDASH ΔFU-6M: 30 ± 24 vs. 18 ± 14, p = 0.029; SF-12 physical component 6.8 ± 12.5 vs. 0.4 ± 8.6, p = 0.031; SF-12 mental component 8.5 ± 9.1 vs. 2.2 ± 12, p = 0.032).

CONCLUSIONS

Self-applied photobiomodulation following RCAS significantly accelerates decrease in pain and disability, and improves QOL. This nonpharmacologic add-on therapeutic modality is easy to use and encourages active patient involvement. Its potential use in rehabilitation following other surgeries should be considered.

LEVEL OF EVIDENCE

Level I, high-quality RCT.

Photobiomodulation and Inorganic Bovine Bone in Guided Bone Regeneration: Histomorphometric Analysis in Rats

The objective of this study was to evaluate the efficacy of photobiomodulation in the bone regeneration of critical-sized defects (CSD) filled with inorganic bovine bone associated or not with collagen membranes. The study has been conducted on 40 critical defects in the calvaria of male rats, divided into four experimental groups (n = 10): (1) DBBM (deproteinized bovine bone mineral); (2) GBR (DBBM+collagen membrane); (3) DBBM+P (DBBM+photobiomodulation); and (4) GBR+P (GBR+photobiomodulation). At 30 days postoperative, the animals were euthanized, and after the tissue had been processed, histological, histometric, and statistical analyses were performed. The analyses have taken into account newly formed bone area (NBA), linear bone extension (LBE), and residual particle area (RPA) as variables. The Kruskal-Wallis test has been performed, followed by the Dwass-Steel-Critchlow-Fligner test for comparison between groups (p < 0.05). When the DBBM+P group was compared to the DBBM group, it was possible to observe significant statistical differences in all the variables analyzed (p < 0.05). The application of photobiomodulation in guided bone regeneration (GBR+P) has shown a decrease in the median value for the RPA variable (26.8) when compared to the GBR group (32.4), with a significant statistical difference; however, for NBA and LBE, the therapy has not provided significant results.

Photobiomodulation therapy mitigates cardiovascular aging and improves survival

BACKGROUND

Photobiomodulation (PBM) therapy, a form of low-dose light therapy, has been noted to be effective in several age-associated chronic diseases such as hypertension and atherosclerosis. Here, we examined the effects of PBM therapy on age-associated cardiovascular changes in a mouse model of accelerated cardiac aging.

METHODS

Fourteen months old Adenylyl cyclase type VIII (AC8) overexpressing transgenic mice (n = 8) and their wild-type (WT) littermates (n = 8) were treated with daily exposure to Near-Infrared Light (850 nm) at 25 mW/cm2 for 2 min each weekday for a total dose of 1 Einstein (4.5 p.J/cm2 or fluence 3 J/cm2 ) and compared to untreated controls over an 8-month period. PBM therapy was administered for 3.5 months (Early Treatment period), paused, due to Covid-19 restrictions for the following 3 months, and restarted again for 1.5 months. Serial echocardiography and gait analyses were performed at monthly intervals, and serum TGF-β1 levels were assessed following sacrifice.

RESULTS

During the Early Treatment period PBM treatments: reduced the age-associated increases in left ventricular (LV) mass in both genotypes (p = 0.0003), reduced the LV end-diastolic volume (EDV) in AC8 (p = 0.04); and reduced the left atrial dimension in both genotypes (p = 0.02). PBM treatments substantially increased the LV ejection fraction (p = 0.03), reduced the aortic wall stiffness (p = 0.001), and improved gait symmetry, an index of neuro-muscular coordination (p = 0.005). The effects of PBM treatments, measured following the pause, persisted. Total TGF-β1 levels were significantly increased in circulation (serum) in AC8 following PBM treatments (p = 0.01). We observed a striking increase in cumulative survival in PBM-treated AC8 mice (100%; p = 0.01) compared to untreated AC8 mice (43%).

CONCLUSION

PBM treatment mitigated age-associated cardiovascular remodeling and reduced cardiac function, improved neuromuscular coordination, and increased longevity in an experimental animal model. These responses correlate with increased TGF-β1 in circulation. Future mechanistic and dose optimization studies are necessary to assess these anti-aging effects of PBM, and validation in future controlled human studies is required for effective clinical translation.

Full-Body Photobiomodulation Therapy Is Associated with Reduced Sleep Durations and Augmented Cardiorespiratory Indicators of Recovery

Research is emerging on the use of Photobiomodulation therapy (PBMT) and its potential for augmenting human performance, however, relatively little research exists utilizing full-body administration methods. As such, further research supporting the efficacy of whole-body applications of PBMT for behavioral and physiological modifications in applicable, real-world settings are warranted. The purpose of this analysis was to observe cardiorespiratory and sleep patterns surrounding the use of full-body PBMT in an elite cohort of female soccer players. Members of a women’s soccer team in a “Power 5 conference” of the National Collegiate Athletic Association (NCAA) were observed across one competitive season while wearing an OURA Ring nightly and a global positioning system (GPS) sensor during training. Within-subject comparisons of cardiorespiratory physiology, sleep duration, and sleep composition were evaluated the night before and after PBMT sessions completed as a standard of care for team recovery. Compared to pre-intervention, mean heart rate (HR) was significantly lower the night after a PBMT session (p = 0.0055). Sleep durations were also reduced following PBMT, with total sleep time (TST) averaging 40 min less the night after a session (p = 0.0006), as well as significant reductions in light sleep (p = 0.0307) and rapid eye movement (REM) sleep durations (p = 0.0019). Sleep durations were still lower following PBMT, even when controlling for daily and accumulated training loads. Enhanced cardiorespiratory indicators of recovery following PBMT, despite significant reductions in sleep duration, suggest that it may be an effective modality for maintaining adequate recovery from the high stress loads experienced by elite athletes.

Therapeutic Efficacy of Home-Use Photobiomodulation Devices: A Systematic Literature Review

Objective: Perform systematic literature review on photobiomodulation (PBM) devices used at home for nonesthetic applications. Background: Home-use PBM devices have been marketed for cosmetic and therapeutic purposes. This is the first systematic literature review for nonesthetic applications. Methods: A systematic literature search was conducted for PBM devices self-applied at home at least thrice a week. Two independent reviewers screened the articles and extracted the data. Treatment dosage appropriateness was compared to the World Association for Laser Therapy (WALT) recommendations. The efficacy was evaluated according to the relevant primary end-point for the specific indication. Results: Eleven studies were suitable. Devices were applied for a range of indications, including pain, cognitive dysfunction, wound healing, diabetic macular edema, and postprocedural side effects, and were mostly based on near-infrared, pulsed light-emitting diodes with dosages within WALT recommendations. Regarding efficacy, studies reported mostly positive results. Conclusions: Home-use PBM devices appear to mediate effective, safe treatments in a variety of conditions that require frequent applications. Conclusive evaluation of their efficacy requires additional, randomized controlled studies.

Therapeutic Efficacy of Home-Use Photobiomodulation Devices: A Systematic Literature Review

OBJECTIVE

Perform systematic literature review on photobiomodulation (PBM) devices used at home for nonesthetic applications.

BACKGROUND

Home-use PBM devices have been marketed for cosmetic and therapeutic purposes. This is the first systematic literature review for nonesthetic applications.

METHODS

A systematic literature search was conducted for PBM devices self-applied at home at least thrice a week. Two independent reviewers screened the articles and extracted the data. Treatment dosage appropriateness was compared to the World Association for Laser Therapy (WALT) recommendations. The efficacy was evaluated according to the relevant primary end-point for the specific indication.

RESULTS

Eleven studies were suitable. Devices were applied for a range of indications, including pain, cognitive dysfunction, wound healing, diabetic macular edema, and postprocedural side effects, and were mostly based on near-infrared, pulsed light-emitting diodes with dosages within WALT recommendations. Regarding efficacy, studies reported mostly positive results.

CONCLUSIONS

Home-use PBM devices appear to mediate effective, safe treatments in a variety of conditions that require frequent applications. Conclusive evaluation of their efficacy requires additional, randomized controlled studies.