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November 1, 2026

Photobiomodulation Research Update - October 2026

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Photobiomodulation: Key Takeaways from October 2026

As of October 2026, PubMed had indexed 152 references on photobiomodulation. We cite 76 of them. The best-supported findings relate to mucositis, chronic wounds, and dentistry. Four studies found no effect.

Photobiomodulation (PBM) involves applying low-intensity red or near-infrared light to tissues. This monthly review compiles relevant publications on the subject.

Updated: November 1, 2026.

This Month's Numbers

152 references indexed in PubMed from October 1 to 31, 2026.
76 studies cited, each with a link to the original publication.
4 studies that found no effect of PBM.
4 trials in which PBM performed worse than an active comparator.
12 PBM trials registered on ClinicalTrials.gov, with no published results.

Three observations

Dentistry and neurology dominate. Of the 76 studies cited, 19 are in dentistry and 15 in neurology. Many are reviews or preclinical studies.
There are many cases with no results: stress fractures, chronic low back pain, pain after a cesarean section, and perineal pain.
Some comparison sites do a better job. Hyaluronic acid spray, apitoxin gel, shock waves, and antibiotics.

We keep all of that on the list. A column that only publishes good news isn't credible.

Table of Contents

Oncology and supportive care
Pain and the Temporomandibular Joint
Chronic Pain and the Musculoskeletal System
Oral Health
Neurology and Mental Health
Ophthalmology
Wound Healing, Bones, and Recovery
Mechanisms and Overview
Other Applications
Ongoing Tests
How We Selected the Studies
Frequently Asked Questions
Key Takeaways

Oncology and Supportive Care: Mucositis Takes Center Stage

In oncology, PBM is used as supportive care. It does not treat cancer.

Mucositis in Children: 30 Seconds vs. 6 Minutes

A pediatric study compares two methods of light therapy. It involves 155 children and adolescents receiving high-dose methotrexate (for leukemia, lymphoma, and osteosarcoma).

Mucositis: 41.1% with intraoral application, 30.5% with extraoral application (p = 0.168).
Session duration: about 6 minutes versus 30 seconds.
Identical dosimetry: 660 nm, 100 mW, 1 J per point.
Median pain score: 0 in both groups.

The results are comparable, but extraoral application is much faster. The study compares two application methods, not PBM to a placebo (DOI).

Head and Neck Cancers

A retrospective cohort study followed 117 patients undergoing chemoradiotherapy with concomitant PBM. At the end of treatment:

38.5% of patients experienced grade 2–3 mucositis.
25.6% of grade 2–3 radiation dermatitis cases.
With at least 10 sessions (72 patients), the incidence of grade 2–3 odynophagia was lower: 16.7% versus 42.2% (p = 0.005).
With at least 10 sessions, there was less persistent dysphagia at the last follow-up: 12.5% versus 33.3% (p = 0.009).

Limitation: The study is retrospective and lacks a strict control group. The comparison with historical cohorts remains indicative (DOI).

Review Articles and Preclinical Studies

Biophotonics in oral health. A review in the Journal of the American Dental Association ranks PBM among the best-supported applications. It carries a guideline-level recommendation for the prevention of oral mucositis. The other two applications deemed clinically supported are PDT for oral leukoplakia and fluorescence for dental caries (DOI).
Oral microbiome. A critical review notes that direct clinical evidence remains scarce and inconsistent (a pilot study of 4 patients, an ENT case series showing no significant change in salivary flora). The microbiome is an emerging hypothesis, not an established mechanism (DOI).
Fertility in mice. Following cisplatin treatment, a low-power pulsed laser (4 J/cm²) improves sperm count and motility (p ≤ 0.0001) and reduces TNF-α and IL-1β. This is preclinical research: there is no approved indication yet (DOI).

Jaw Pain: Is PBM as Effective as a Mouthguard?

Five studies on temporomandibular disorders (TMD) all come to the same conclusion: PBM provides relief, but its advantage over a placebo has not been established.

Two clinical trials

PBM versus mouthguard (PLoS One). Acute masticatory myalgia. 660-nm laser, twice a week, 10 sessions. Each treatment is combined with a self-care program. Of the 66 patients enrolled (44 randomized), both treatment arms showed faster improvement than self-care alone. At 48 weeks, pain (VAS) and pain-free mouth opening were comparable between PBM and the mouthguard (DOI).
Laser diode bi-longueur d’onde. 24 patients avec douleur myogène de l’articulation temporo-mandibulaire (12 par groupe), 9 séances, associées aux médicaments. L’EVA baisse davantage avec le laser à 10 jours, 21 jours et 3 mois (p < 0,05). L’ouverture buccale progresse aussi davantage. Il n’y a pas de laser placebo (DOI).

Three magazines that offer a more balanced perspective

Systematic review (Quintessence International). 9 reports (8 cohort studies), wavelengths ranging from 635 to 940 nm, energy densities ranging from 5 to 300 J/cm². Pain decreased in most PBM groups, but the placebo groups often showed similar improvement. Three out of five myogenic cohorts support PBM, while two do not. No trial reported all parameters recommended by WALT. The certainty of the evidence is low for myogenic conditions and very low for joint conditions (DOI).
Scoping review. Of 175 controlled trials, the wavelength and number of sessions were reported in 95% of cases. Power density was reported in 12% of cases, and total energy in 14%. Only 19% provided the minimum set of parameters necessary for reproducibility. 27% were non-reproducible (DOI).
PBM vs. TENS. Systematic review of 14 studies (620 patients). More studies report a numerically greater improvement in pain and mouth opening with PBM. However, 12 of the 14 studies are Level III, and heterogeneity precludes a conclusion of superiority (DOI).

Our take. PBM is just as effective as a splint in relieving muscle pain at the one-year mark. This is useful in practice. Its advantage over a placebo has not been established. The first obstacle is the lack of rigor in reporting the parameters. Our dosimetry calculation tool is specifically designed to determine these figures before drafting a protocol.

Chronic Pain and the Musculoskeletal System

Chronic low back pain: no effect in 148 adults

A randomized, placebo-controlled trial is testing the addition of PBM to a motor control exercise program. Patients, therapists, and evaluators are blinded. 12 sessions over 6 weeks.

Pain at 6 weeks: mean difference of -0.4 on a 10-point scale (95% CI -1.2 to 0.4).
No significant effect on disability or on circulating prostaglandin E2.
No difference up to 12 months.

This is one of the most robust null results of the month in terms of sample size. We were unable to access the full text; the class and exact power of the model are unknown to us (DOI).

Cesarean Section and Perineal Pain: Two More Null Results

After cesarean section. Randomized trial of 88 women divided into four groups (TENS plus PBM, TENS, placebo, control). 660-nm laser, 2 J per point (100 mW, 20 seconds), 2 sessions. Pain and functional independence improved over time, with no differences between the groups (p > 0.05). TENS plus PBM provided no additional benefit (DOI).
Perineal pain. Meta-analysis of 9 randomized trials following episiotomy or obstetric trauma. No significant benefit from LLLT (SMD -0.16; 95% CI -0.52 to 0.19). TENS reduces pain in the short term (SMD -1.19; 95% CI -1.83 to -0.55) (DOI).

Painful Diabetic Neuropathy

A multicenter, double-blind, placebo-controlled trial involving 64 adults. A dual-wavelength laser (640 and 405 nm, 15 mW total, Class 2) was used at home twice daily for 3 weeks.

Pain reduced by at least 30%: 72.7% versus 32.3% with the placebo (p = 0.0024).
The effect persisted at 7 weeks.
No serious adverse events.

Three caveats. The manufacturer (Erchonia) funded the study, and two of its employees are among the authors. Follow-up ended 4 weeks after the end of treatment. Finally, 405 nm is violet light, outside the red and near-infrared windows (DOI).

In rats with neuropathic pain, PBM at 660 and 904 nm (45 mW, 6 J/cm²) reduces mechanical hyperalgesia and tactile allodynia. It does not restore mitochondrial respiration in muscle, but it increases OPA1 (DOI).

Shoulder, carpal tunnel, elbow

Two reviews on the shoulder combine low- and high-power lasers. Only the non-thermal mode is relevant to us: read them with caution.

Rotator cuff. Meta-analysis of 23 randomized trials. Laser therapy reduces overall pain (VAS, mean difference -5.22; 95% CI -7.56 to -2.88). No significant effect on pain at rest, during movement, or at night. High-power laser therapy performed better than LLLT for active abduction (p = 0.016) (DOI).
Shoulder, 20 trials. 1,153 patients. A small but significant effect of PBM at the end of treatment, but not significant at follow-up. Only high-power laser therapy showed a clear effect (DOI).
Subacute carpal tunnel syndrome. A randomized trial of 69 patients divided into three groups: LLLT (860 nm, 50 mW), high-intensity laser (808 nm, 4.6 W), and control. At 6 weeks, pain decreased by 4.1 points with LLLT compared to 2.2 points in the control group. The high-intensity laser performed even better (-4.9), but its mechanism of action is thermal; therefore, this arm was excluded from our analysis (DOI).
Lateral epicondylitis. Single-blind, non-placebo-controlled trial. At 3 weeks, shockwave therapy outperformed LLLT in terms of pain (p = 0.004) and tendon thickness (p = 0.021). No difference was observed in grip strength (DOI).

Oral Health: PBM in Surgery, Pediatrics, and Orthodontics

Surgery and Wound Healing

Wisdom teeth. Review of 36 randomized trials (1,838 participants): 13 evaluated corticosteroids, 11 evaluated NSAIDs, 7 evaluated physical therapy, and 5 compared multiple approaches. Corticosteroids primarily reduce swelling and trismus. NSAIDs have a more pronounced effect on pain. Physical therapy yields mixed results, depending on the protocol (DOI).
Periodontal surgery. 16 studies, 660 to 970 nm, highly heterogeneous parameters. Potentially beneficial effects on healing and pain, but inconsistent. Some studies show no improvement. No optimal settings have been established (DOI).
Coronary bone lengthening. 5 studies, including 2 on adjuvant PBM. Early postoperative pain reduced at certain time points. The risk of bias is a concern or high for all randomized trials (DOI).

In children

Fin de l’anesthésie. Essai croisé en bouche divisée, préliminaire, sur 34 enfants de 8 à 12 ans. PBM 810 nm après extraction d’une dent temporaire. La sensation normale revient en 60,7 ± 27,3 minutes avec la PBM, contre 78,2 ± 17,0 minutes avec le laser factice (p < 0,001). Un gain d’environ 17 minutes : modeste, mais utile chez un enfant qui se mord la lèvre (DOI).
Stress during dental treatment. A split-mouth trial involving 30 children aged 7 to 12 years, using a near-infrared multi-wavelength LED. During the cold test, heart rate varied by 2.23 beats per minute with PBM, compared to 6.07 with the control (difference -3.83; 95% CI -6.89 to -0.77; p = 0.016). Pain during gingival probing was lower (p = 0.004). No adverse events were reported. This publication does not have a DOI in PubMed: see its PubMed record.

When PBM Performs Less Well

After gingivectomy. Randomized trial of 64 patients. 940-nm laser (4 sessions, 3 W continuous wave, high power for PBM; the authors describe a non-thermal effect), compared with a 0.04% hyaluronic acid spray applied twice daily. The spray was superior in terms of epithelialization on days 3, 7, and 14 (effect sizes 1.39, 1.12, and 0.73) and in terms of pain on days 1 and 3 (DOI).
Aphtose récurrente. Essai de 60 patients : gel d’apitoxine contre diode 806 nm (60 mW, 6,3 J/cm², 4 séances). Les deux groupes s’améliorent (p < 0,001). Le gel fait mieux sur la douleur, l’indice d’efficacité et la profondeur de l’ulcère (p < 0,001), sans différence sur la surface (p = 0,21) (DOI).

Orthodontics and Implants

Canine distalisations. 16 patients; 850-nm LED versus sham device. Lower cumulative pain (group × time interaction, p = 0.024) and lower levels of dentin sialoprotein in gingival fluid (p = 0.021) (DOI).
Implant stability. 10 participants, 40 implants in a split-mouth design, 940-nm laser. Better stability on the PBM side at 2 months (difference 6.30; 95% CI 1.21 to 11.39; p = 0.016), but no longer significant at 3 months (p = 0.878) (DOI).

Both of these trials are positive, but small.

Other journals and animal studies

Rat, palatal healing. 660 nm PBM (150 mW, 4.2 J/cm²): better re-epithelialization on day 7 compared to the control (adjusted p-value = 0.024). A hyaluronic acid-chitosan gel performed better than the control on days 3 and 7, and better than PBM on day 3 (DOI).
Sensitivity after bleaching. An umbrella review of 18 systematic reviews. PBM appears promising for reducing sensitivity, but confidence is limited by the heterogeneity of the protocols. Systemic NSAIDs show no preventive effect (DOI).
PRP and PRF. A narrative review supports the combination of PBM with platelet-rich plasma and platelet-rich fibrin. It calls for standardization before any clinical validation (DOI).

Basic Research on Dental Cells

The Wnt/β-catenin pathway in apexogenesis under PBM: a review highlighting the lack of clinical evidence (DOI).
Acceleration of Orthodontic Movement: A Review Finds Inconsistent Clinical Results (DOI).
940-nm Laser on Human Periodontal Ligament Stem Cells: The Effect Depends on Fluence (DOI).
450- and 980-nm lasers on comparable cells: both increase proliferation and osteogenic differentiation (980 nm is the most effective). Their combination does not improve outcomes and causes the most apoptosis. Note: 450 nm is blue light (DOI).
630 nm LED: most consistently reduces pro-inflammatory cytokines and nitric oxide compared to 525 and 850 nm. Increases alkaline phosphatase and RUNX2 at 5 and 10 J/cm² (DOI).
Deciduous tooth stem cells on polylactic acid films: PBM at 660 nm, increased metabolic activity at 4 J/cm² (24, 48, and 72 hours) and at 1 J/cm² (48 and 72 hours) (DOI).
LLLT-preconditioned dental pulp stem cells: increased odontogenic activity of their extracellular vesicles. The dual protocol (odontogenesis plus LLLT) outperforms either treatment alone (DOI).

Neurology and Mental Health: Primarily Mechanisms

Human Trials

Bipolar disorder in remission. 29 participants; six weekly sessions of transcranial infrared laser stimulation of the frontopolar regions. Perfusion MRI showed increased cerebral blood flow in certain frontal areas after the first session, followed by a decrease after the sixth session. This biphasic pattern is intriguing. The study makes no mention of any clinical effect (DOI).
Volontaires sains. Essai randomisé en double aveugle contre placebo, 60 personnes, 4 jours de PBM transcrânienne à 850 nm (60 mW/cm², 36 J/cm²) sur l’aire motrice supplémentaire. Temps de réaction et temps total de mouvement diminuent. La précision de la main non dominante progresse (tous p < 0,001). La puissance alpha et bêta augmente sur C3 et C4 (p < 0,001) (DOI).
Acute concussion in athletes. RECOVERY pilot trial, 50 athletes, two pulse frequencies (5 and 10 Hz) of cerebral PBM combined with a static magnetic field. 98% completed the study. No differences were observed between the groups. Mild adverse events occurred in approximately 4 out of 10 athletes. No placebo control group was included, so no conclusions regarding efficacy can be drawn. The sponsor is an industry partner (DOI).
Paralysie de Bell. Essai à quatre bras, 104 patients : un sham et trois protocoles laser (deux en LLLT à 808 et 980 nm, un en haute intensité à 1064 nm). Les différences globales sont significatives sur les paramètres neurophysiologiques et fonctionnels (p < 0,001). Le protocole 1064 nm, thermique, l’emporte. Seuls les bras LLLT relèvent de notre périmètre, et le résumé ne permet pas d’en isoler les chiffres (DOI).

Journals: Parkinson's disease, Alzheimer's disease, depression

These reviews are worth reading for their biological consistency and historical context. They do not constitute clinical evidence. PBM is not a substitute for monitoring or treatment.

Parkinson's Disease. Neuroprotective signals in experimental models. Preliminary and inconsistent clinical data on safety and symptomatic benefit (DOI).
Neuroinflammation (Frontiers in Neurology). Encouraging results for Alzheimer’s disease and multiple sclerosis, but mostly negative results on the primary endpoints for Parkinson’s disease and major depression (DOI).
Astrocytes. A review examines their role in neuro-rehabilitation using near-infrared light (DOI).
NEST Program. Transcranial PBM at 808 nm for depression. NEST-1 met its primary endpoint. NEST-2 showed a non-significant trend (p = 0.094). NEST-3 was terminated due to futility (DOI).

Animal and cellular models

Alzheimer's disease (APPswe/PS1dE9 mice). Dosimetry-guided LED PBM (810 nm continuous plus 1060 nm pulsed at 40 Hz, 20 minutes per session). Improved spatial learning and memory. Combined irradiation of the hippocampus yields the most consistent results (DOI).
Migraine (nitroglycerin model). 9 days of transcranial PBM at 810 nm. Reduced photophobia and mechanical allodynia. Lowered miR-155 and inflammatory mediators in the trigeminal nucleus (DOI).
Alexander’s disease. Cell and mouse model: 1070-nm light regulates the AMPK/mTOR pathway, promotes mitophagy, and reduces free radicals from fragmented mitochondria (DOI).
Simulated microgravity. Mice, 28 days: Transcranial PBM at 810 nm reduces anxiety- and depression-like behaviors (DOI).
Fear in Rats. A single session of PBM at 808 nm reduces risk-assessment behaviors in the presence of a snake (DOI).

In mice, in rats: not yet in astronauts or patients.

Ophthalmology: Can Red Light Slow the Progression of Myopia?

Myopia and Pre-myopia in Children

Pre-myopia. Meta-analysis of 8 randomized trials (7 in China, 1 in India). At 12 months, 0.01% atropine reduced myopic progression by 0.32 diopters (95% CI 0.12 to 0.52; low certainty). Repeated low-intensity red light (RLRL) shows similar results, with a reduction of 0.38 diopters across 2 studies and 307 participants. However, the confidence interval (-0.05 to 0.81) includes zero, and the certainty is very low (DOI).
Choroid. Meta-analysis of 13 randomized trials (1,974 children). The choroid thickens by 37 µm at 9 months with RLRL. This is an intermediate endpoint: it supports the hypothesis of a mechanism but does not prove a slowing of myopia (DOI).
Severe myopia. Cohort of 30 children followed for 12 months, with no control group. Myopic refraction reduced by 0.29 diopters, axial length stabilized (-0.03 mm), choroid thickened by 26 µm. One case discontinued due to photophobia (DOI).

The lead is promising, but the evidence isn't there yet. Regular eye exams remain essential.

Dry eyes

A meta-analysis of 10 studies (473 participants) found that LLLT (625 to 640 nm and 810 to 850 nm) was associated with an improvement in:

du score OSDI (différence moyenne -11,42 ; p < 0,00001),
the tear film break-up time (+1.49 s; p = 0.005),
the height of the lacrimal meniscus (+0.04 mm; p = 0.007).

Sensitivity analyses based solely on randomized trials confirm the OSDI and time to rupture, but not the meniscus. No adverse events were reported (DOI).

Wound Healing, Bones, and Recovery

Chronic Wounds and Pressure Ulcers

Escarres (Suède). Étude quasi-expérimentale de 24 mois sur 76 personnes fragiles de 70 ans et plus, soignées à domicile (catégorie II : 39, catégorie III : 37). PBM en complément des soins standard (lasers 904 et 635 nm, deux séances par semaine), comparée à 228 témoins appariés du registre RiksSår. Délais médians de cicatrisation : 33 et 70 jours avec la PBM, contre 153 et 195 jours chez les témoins (catégories II et III ; p < 0,001). Récidive à 24 mois : 0 % et 6,7 %. Les témoins ne sont pas randomisés (DOI).
Ulcères veineux ou diabétiques. Essai randomisé en double aveugle contre placebo, 70 patients, laser 904 nm (60 mW, 8 J/cm²) avec les soins standard. La surface de la plaie diminue de 53 % avec le laser contre 9 % avec le placebo (p < 0,001). Moins de bactéries colonisantes (DOI).

Stress fractures: no effect

A randomized, placebo-controlled trial in military recruits with stress fractures of the tibia or metatarsal (103 randomized, 97 analyzed).

Time to graduation: HR 0.95 (95% CI 0.61–1.48; p = 0.83).
There is no difference in the degree completion time.
No difference in bone healing was observed on MRI.

PBM is not a substitute for resting a sore bone (DOI).

Animal and Cell Studies

Achilles tendon (rat, 144 animals). PBM and platelet-rich plasma each reduce IL-1β and TNF-α and improve collagen organization. The combination produces the most pronounced response (DOI).
Muscle injury caused by venom (mouse). A 945-nm LED reduces the inflammatory infiltrate, leukocyte recruitment, and IL-6, either alone or in combination with antivenom, which is not very effective on its own (DOI).
Macrophages. PBM selectively and transiently modulates inflammatory and metabolic markers without inducing classical polarization (DOI).

Mechanisms and Overview

This Month's "Parapluie" Magazine: 100 Magazines Under the Microscope

This is the most useful publication for anyone seeking an overview. It compiles 100 systematic reviews (790 individual primary studies) on LLLT.

Fields: oral health (53 journals), musculoskeletal (22), oncology complications (8), wounds and lymphatic disorders (8).
Conclusions: 62 reviews in favor of the intervention, 34 neutral or mixed, 4 inconclusive.
Oncology: the highest proportion of favorable outcomes.
Safety: 32 reviews report no adverse events, 11 report at least one, and 57 do not mention any.

The lack of safety data is a weakness in the literature (DOI).

Mechanisms: What the Journals Say

Red and Near-Infrared PBM in Precision Medicine: Mechanisms, Dosimetry, and Clinical Application (DOI).
Skeletal muscle: effects on cytochrome c oxidase (dissociation of nitric oxide, increase in ATP, ROS signaling), biphasic dose-response relationship. Clinical variability is due to dosimetry, the optical properties of tissues, and uncertainty in light delivery (DOI).
Red Light, Mitochondrial Rejuvenation, and Age-Related Diseases (DOI).
PBM as an antioxidant intervention following myocardial infarction (DOI).
The TGF-β/Smad pathway in stem cell osteogenesis (DOI).
Inner ear: a working model linking the mitochondrial response of PBM to the Wnt/β-catenin and Notch/HES5 pathways. The only organoid study cited remains exploratory (DOI).
Historical review of the Munich Laser Center in the late 1990s: comparison of normal and tumor cells; wavelength studies. These safety data supported applications in supportive cancer care (DOI).

In the laboratory and in tissue engineering

Synovial cells. Irradiation at 660 and 980 nm (500 mW): increased viability, activation of the TRPV4/PI3K/AKT/mTOR pathway, and modulation of interleukins. 660 nm is comparable to 980 nm (DOI).
Red OLEDs. Wavelengths of 610 nm and 610–650 nm increase cell proliferation compared to the placebo. The widest light source produces the strongest effect (DOI).
Rabbit tracheal cartilage (LED 660 nm). Stem cells preconditioned prior to implantation onto a scaffold. A dose of 15 J/cm² yields the best in vitro results, via cytochrome c oxidase, ATP, and the PI3K/Akt/mTOR pathway (DOI).
Rabbit tracheal cartilage (940 nm). An irradiance of 50 J/cm² most strongly promotes proliferation and matrix formation. A matched thermal control does not reproduce this effect, suggesting a photobiological mechanism (DOI).

Other Applications

Otite externe chronique. Essai pilote randomisé de 21 patients. LED 660 et 940 nm, seule ou avec antibiotique, contre ofloxacine seule. Résolution complète de l’otorrhée : 75,0 % avec l’antibiotique, 25,0 % avec la LED, 20,0 % avec l’association (p = 0,194). Sur le critère principal, la PBM ne fait pas mieux. La gêne baisse néanmoins avec la LED (de 7,00 à 3,00 ; p < 0,05), sans événement grave. L’appareil produit un léger effet thermique régulé : réserve sur le caractère strictement non thermique (DOI).
Réhabilitation respiratoire après tuberculose. Étude prospective contrôlée non randomisée de 65 patients. LLLT 808 nm (100 mW, 7 J/cm²) plus oscillation profonde. Le groupe combiné gagne 6,46 points de qualité de vie (EUROHIS-QOL-8) et 14,69 m au test de marche de 6 minutes (tous p < 0,001). Le design et la co-intervention ne permettent pas d’isoler l’effet de la lumière (DOI).
Facial rejuvenation. Systematic review of 8 studies (365 participants) on at-home LED therapy. Significant improvements in wrinkles, skin texture, and elasticity. High satisfaction, rare and transient adverse effects. Variable protocols, limited comparative data (DOI).

Ongoing trials: published protocols and the ClinicalTrials.gov registry

Five protocols published in the literature

They have no results. We draw no conclusions from this.

PBM Combined with a Static Magnetic Field in Ventilated Patients in the ICU: A Multicenter, Triple-Blind Trial (DOI).
Shock Waves vs. LLLT in Myogenic Musculoskeletal Disorders (DOI).
LLLT and Condylar Locator in Children with Skeletal Class II Malocclusion: A Two-Phase Protocol (DOI).
Flapless Implant Surgery with PBM: Nonclinical Setting (DOI).
Management of Myopia in Children with Intermittent Exotropia: A Review Protocol in Which Repeated Red Light Therapy Is Just One of Several Interventions (DOI).

Preprints were not systematically searched for in this edition; none are cited.

Twelve PBM trials were registered on ClinicalTrials.gov in October

In October 2026, 26 records were published for the first time in the registry involving light- or laser-based procedures. After sorting, twelve of these pertained to non-thermal PBM. We excluded high-intensity lasers, CO₂ lasers, Nd:YAG lasers, nanoparticle-based photothermia, and imaging devices.

A record entered in October does not necessarily mean that the study began in October. Several studies began between 2022 and 2025 and were recorded retroactively.

Nine trials coming up or currently underway:

NCT07863960: PBM versus placebo for pain after cesarean section, in Honduras (210 women, starting October 1, 2026).
NCT07865325: Patellar tendinopathy in adolescent girls in Egypt (104 patients).
NCT07866716: Chronic wound pain in Colombia (32 patients).
NCT07899866: Observational cohort study of prophylactic PBM for radiation dermatitis in head and neck cancers at Forcilles Hospital (150 patients).
NCT07886723: Pain after root canal treatment, at the University of Minnesota (60 patients).
NCT07878884: A clinical trial on respiratory rehabilitation in COPD in Brazil (20 patients).
NCT07865780: Radiation-induced oral mucositis; PBM alone or in combination with oxygen gel, in Assiut (46 patients).
NCT07878247: Laser therapy combined with a mouthguard for temporomandibular disorders in Egypt (24 patients).
NCT07873853: Acceleration of tooth movement using low-power lasers at Al-Azhar (24 patients).

Three trials have already been completed, with no results published: bruxism in children (laser vs. mouthguard, NCT07865845) and two orthodontic studies (NCT07888231, NCT07852559).

Two study protocols received their results in October: the PBM 940 nm study following gingival grafting (NCT07308912) and the LIGHTSITE III study on dry age-related macular degeneration (NCT04065490). We have only read the study protocols, not the results themselves.

The registry is based on self-reporting. A “pending” status does not prove that recruitment has actually taken place, and some dates are inconsistent. Two laser diode entries on peri-implant mucositis were not included: the intended effect is likely antimicrobial, not PBM.

How We Selected the Studies

We search PubMed every month using a broad search query. Keywords: photobiomodulation, low-level laser therapy, LLLT, low-level light therapy, red light therapy, and near-infrared light, in the title or abstract.

Comprehensive review. We reviewed all 152 references: study titles and types, followed by abstracts of the eligible studies.
Scope. We are focusing on non-thermal PBM. We are excluding high-intensity lasers with thermal effects, ablative, cosmetic, or vascular lasers, dynamic phototherapy, protocols with no proven results, and studies not directly related to light.
Noise. The broad search terms yield results on photothermal nanomaterials, photochemistry, imaging, and sensors. A significant portion of the references has no connection to therapeutic PBM.
Verification. When the full text was available, we verified the efficacy and mechanism of action of the devices.
Negative results. They are included in the list, just like positive results.

Frequently Asked Questions About Photobiomodulation

What is photobiomodulation?

Photobiomodulation (PBM) is the application of low-intensity red or near-infrared light to tissues. This report focuses solely on non-thermal PBM, in which heating is not the intended effect.

Is photobiomodulation as effective as a mouthguard for jaw pain?

Regarding acute masticatory myalgia, a 48-week trial found comparable results between PBM and a stabilization splint. However, a systematic review published that same month rated the certainty of the evidence as low. The placebo groups often showed similar improvement.

Can light be used to prevent mucositis in children?

A trial involving 155 children on high-dose methotrexate compared two methods of administration. The 30-second extraoral application yielded results comparable to those of the 6-minute intraoral application. The study did not compare PBM to a placebo.

Can red light slow the progression of nearsightedness?

The October data support this conclusion, but the level of certainty remains very low in the meta-analysis on pre-myopia, as the confidence interval includes zero. The cohort study on high myopia lacks a control group. Ophthalmological follow-up remains essential.

Which studies published in October found no effect of PBM?

Four. The trial on stress fractures in military recruits, the trial on chronic low back pain in 148 adults, the trial on pain after cesarean section (88 women), and the LLLT subgroup of a meta-analysis on perineal pain. The three trials are randomized and compared against placebo, sham, or a control group.

Should physical therapy be added to the exercise regimen for chronic lower back pain?

Not according to a trial involving 148 adults. The effect on pain and disability is negligible compared to a placebo, for up to 12 months.

Are the side effects of PBM well documented?

Not enough. Of 100 systematic reviews, 57 report no safety data. The other 43 do not identify any widespread serious events, but the gap is real.

What is the difference between PBM and high-intensity laser therapy?

PBM uses low power and does not rely on a thermal effect. High-intensity lasers work through a thermal effect. Several October journal articles confuse the two, which makes it difficult to interpret the results.

Key Takeaways

October 2026 doesn't include any disruptions, which is actually quite reassuring.

The areas with the strongest evidence: supportive oncology (mucositis, toxicities from chemoradiation), chronic wounds, and dentistry. The umbrella review confirms this on a large scale.
The weakest area: neurological evidence, which is advancing primarily in the areas of mechanisms and animal models.
Limitations: four studies showing no effect (stress fractures, low back pain, cesarean section, perineal pain) and four trials in which PBM performed worse than an active comparator (gingivectomy, canker sores, epicondylitis, otitis). PBM is not a universal treatment.
The common thread: wavelength, dose, and the number of sessions vary widely from one trial to another. High-intensity lasers are often conflated with LLLT in reviews. Until these parameters are fully reported, comparisons will remain unreliable.

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