Red Light Therapy for Oral Lichen Planus: Scientific Evidence

60 patients with troublesome oral lichen planus who were given low-level laser therapy (LLLT) alongside steroid treatment had lower pain scores than those given steroids alone, in a 2023 randomized controlled trial in India. Patients were randomly split into 2 groups, with the LLLT group receiving an 810 nm laser at 800 to 900 mW for 10 minutes, held close to the patch, over 28 days. Only the combined group saw pain fall to 2.5 by day 21, against 4.63 with steroids alone, and to 1.3 against 3.0 by day 28, while burning scored 1.1 against 3.4 at day 45.

Researchers in Italy looked back at 20 patients given a single photobiomodulation (PBM) session for painful oral lichen planus in a 2023 observational study. The 12 women and 8 men, average age 59, received a 980 nm diode laser at 500 mW, 500 mW/cm², and 10 J/cm² for 20 seconds per spot without contact, through a 1 cm flat-top handpiece. Pain scores fell from 3.8 before treatment to 2.6 right after, 1.9 the next day, and 1.5 at day 30, each a significant drop. No side effects occurred, and 6 patients asked for further sessions.

No side effects had been reported for photobiomodulation (PBM) in oral lichen planus, in a 2022 review from Spain of 7 studies with 300 patients. The studies used diode lasers in 4 cases, Nd:YAG lasers at 1064 nm in 2, and a helium-neon laser in 1, with wavelengths from 630 to 1064 nm, mostly compared against steroid treatment. PBM appeared to improve both the signs and the symptoms of eroded patches. PBM was judged more beneficial than steroids because of the side effects steroids can cause.

Pain scores fell by 3.52 points at 30 days and 5.04 points at 60 days after photobiomodulation for gum patches caused by immune conditions such as oral lichen planus, in a 2022 meta-analysis from Brazil. The review included 17 studies, 6 of them pooled, covering 239 participants and lasers from 308 to 1060 nm. The meta-analysis found no significant difference between PBM and steroid treatment in pain relief, and clinical scores also improved significantly at 30 days after PBM.

A 2022 single-blind randomized controlled trial in India compared low-level laser therapy (LLLT) with aloe vera gel in 60 patients with oral lichen planus. 30 patients applied aloe vera gel three times daily for 2 months, and 30 received a 980 nm laser twice a week for 2 months, with follow-up to 9 months. Pain fell by 44.1% with LLLT against 26.7% with aloe vera during treatment, and the laser group also appeared to improve more in the spread and activity of the patches. During follow-up, the 2 groups no longer differed.

Treating 48 patients with a red helium-neon laser and 48 with steroids, a 2021 observational study in Belgium looked back at 96 patients with painful, eroded oral lichen planus. The patients, 64 women and 32 men aged 42 to 68 (average 48), had photobiomodulation at 635 nm and 100 mW for 40 seconds (4 J) in contact with each patch and 5 mm around it, every 48 hours for 6 weeks, or steroid applications. Pain scores fell from about 81 to 84 out of 100 to 0 in both groups after 6 weeks, and clinical scores dropped from 4 to 1 in both. By 12 months, patches had returned in 79% of steroid patients and 87.5% of PBM patients, a difference that was not statistically significant.

A 2-group design compared photobiomodulation (PBM) with a steroid gel in a 2021 clinical trial in Italy of 40 patients with painful, eroded oral lichen planus, using a light-based scanner to measure the mouth lining. 20 patients applied clobetasol 0.05% twice a day for 8 weeks, and 20 received 8 weekly PBM sessions with a 980 and 645 nm diode laser at 400 mW, 800 mW/cm², and 8 J/cm² for 10 seconds, held 2 mm away. According to the trial, the surface layer of the lining thickened significantly in both groups after 8 weeks, more so with clobetasol, but 6 months later only the PBM group had kept that gain.

2021 brought a double-blind randomized controlled trial from Brazil comparing photobiomodulation (PBM) with clobetasol, a strong steroid gel, in 34 patients with painful oral lichen planus. 17 patients applied clobetasol 0.05% three times daily for a month with a placebo laser, and 17 received PBM at 660 nm, 100 mW, 35.4 mW/cm², and 177 J/cm² for 5 seconds per point twice a week for 8 sessions, with a placebo gel. Pain and clinical scores appeared to improve significantly in both groups, with no difference between them in how often patches cleared or came back over 3 months of follow-up. No side effects were reported with PBM.

59.3% of oral lichen planus patches improved and 37.3% cleared completely after low-level laser therapy (LLLT) in a 2018 clinical trial from Bulgaria. 12 patients with long-standing sore, eroded patches, 59 in all, received an 810 nm diode laser at 0.5 W and 1.2 J/cm² for 30 seconds, 3 times a week for a month. Pain fell significantly, and every patient improved to some degree, with most showing moderate recovery, the trial found. LLLT was described as effective and harmless for this form of the condition.

In 2017, a review from Saudi Arabia assessed low-level laser therapy for painful oral lichen planus. Of 227 publications found, 6 studies were included, using lasers from 630 to 980 nm at 20 to 300 mW for 10 seconds to 15 minutes. All 6 studies appeared to find the laser effective, with no side effects reported. Laser therapy was put forward as an alternative to steroids, but the studies varied so much in method and settings that larger trials were called for.

10 of 10 patients with long-standing oral lichen planus had their pain and burning feeling cleared after low-level laser therapy (LLLT) in a 2015 clinical trial in Egypt. They received a 970 nm diode laser at 3 W and 30 Hz for 2 minutes without contact, twice a week for 2 months, up to 10 sessions. Patches also shrank significantly, and no complications or side effects were seen, the researchers reported.

When researchers in Italy treated 30 patients whose oral lichen planus had not responded to standard steroid treatment, a 2014 clinical trial applied low-level laser therapy (LLLT) to 82 patches across the mouth. A 980 nm GaAlAs diode laser at 300 mW, 1000 mW/cm², and 4 J/cm² was applied for about 4 seconds per spot, held 2 mm away, once a week until the eroded patches had cleared. The researchers reported significant falls in clinical scores and pain, with no complications or side effects seen during the study.

Researchers in Brazil compared laser phototherapy (LPT) with clobetasol, a strong steroid gel, in a 2014 randomized controlled trial of 42 patients with sore, eroded oral lichen planus. The patients, 83.3% of whom were women with an average age of 58.2, were split into 21 who applied clobetasol 0.05% gel three times daily. The remaining 21 received an InGaAlP diode laser at 660 nm, 40 mW, 1000 mW/cm², and 6 J/cm² for 6 seconds per point, 3 times a week for 4 weeks. Both groups improved significantly by day 30, but the LPT group held its gains at days 60 and 90 with few patches returning, while the clobetasol group worsened on every measure. 3 clobetasol patients reported a passing burning feeling and 2 had stomach upset, with no side effects in the LPT group.

A 630 nm laser at 10 mW and 1.5 J/cm² was tested in a 2013 report of 2 cases from Iran, patients with eroded oral lichen planus on the tongue edge and the inside of the cheek, who had had no previous treatment. Each session lasted 2 minutes 30 seconds, with 10 sessions over a month. After treatment, both patients had milder patches and less pain, with no side effects reported. The authors suggested the laser could be an alternative treatment, though with only 2 cases and no comparison group, this is a first indication rather than proof.

Comparing low-level laser therapy (LLLT) with carbon dioxide (CO2) laser surgery, a 2012 randomized controlled trial in Iran treated 28 patients (21 women and 7 men) with 57 oral lichen planus patches on the cheeks, gums, and tongue. 1 group of 13 had 27 patches removed with the CO2 laser at 3 W, while the other group received LLLT with red 633 nm and infrared 890 nm light at 0.3 to 0.5 J/cm² in 5 sessions every other day. After 3 months, 100% of LLLT patches showed partial to complete improvement, compared with 85% of those treated with CO2 surgery, the trial found. Patch size, pain, and clinical scores improved in both groups.

Among 30 patients with sore, eroded oral lichen planus, a 2011 randomized controlled trial in Iran compared low-intensity laser therapy (LILT) with a steroid mouthwash. 1 group received a 630 nm diode laser at 10 mW, 10 mW/cm², and 1.5 J/cm² for 2 minutes 30 seconds, while the other used a dexamethasone mouthwash. Appearance, pain, and severity scores fell in both groups, with no significant difference in response or in patches coming back. No side effects were seen with the laser.

13 patients whose oral lichen planus had not responded to standard treatment took part in a 2010 clinical trial in Italy of low-level laser therapy. They received a pulsed GaAs diode laser at 904 nm and 4 J/cm² per minute, with a 0.8 cm spot, on the affected patches of the mouth lining. Patches appeared significantly smaller and pain significantly lower after treatment, though the authors called the results inconclusive. No complications or side effects were seen in any patient.

Whether photobiomodulation therapy (PBMT) beats other treatments for oral lichen planus was the question a 2024 meta-analysis from Malaysia set out to answer. 8 studies were included and 6 pooled, covering 317 patients and lasers from 628 to 808 nm. According to the pooled results, pain and clinical scores did not differ significantly between PBMT and the comparison treatments, including steroids. The authors concluded that PBMT is as effective as other treatments but not superior, and may suit patients who cannot use steroids.

Steroids applied to the mouth remain the standard treatment for oral lichen planus, according to a 2018 review from Bulgaria of what is and is not known about the condition. The review covered its possible causes, diagnosis, and treatments, and noted that drug treatments often give poor results and side effects. Two of the alternatives it listed were low-level laser therapy and photodynamic laser treatment, described as harmless options to prioritize. The authors noted ongoing debate over whether the condition can turn cancerous and advised regular check-ups.

45 adults with sore, eroded oral lichen planus on the tongue or inside of the cheeks showed clearer skin signs with laser treatment than with a steroid, in a 2018 randomized controlled trial from Pakistan. Patients were randomly split into 3 groups receiving a dye activated by a GaAlAs laser at 630 nm and 10 mW/cm², the same laser alone as low-level laser therapy at 10 mW and 1.5 J/cm² for 2 minutes 30 seconds, or a steroid. The trial found that visible signs changed significantly in all 3 groups, with both laser groups differing significantly from the steroid group, while pain eased significantly more with the steroid, and the dye-plus-laser group scored highest on the effectiveness index.

According to a 2018 review from Pakistan, it remains unclear whether low-level laser therapy works better than steroids for oral lichen planus. The review found 5 clinical studies comparing the 2, using lasers from 630 to 970 nm at 10 mW to 3 W, and judged 4 of them to have serious design weaknesses and 1 moderate ones. The authors concluded that the evidence is weak and preliminary, and called for more randomized trials.

Published in 2015, this clinical trial from Egypt compared low-level laser therapy (LLLT) with a steroid paste in 24 patients with sore, eroded oral lichen planus. 1 group received a 970 nm diode laser at 3 W and 30 Hz for 8 minutes without contact over 60 days, while the other applied triamcinolone 0.1% paste. Researchers found that pain scores fell more in the steroid group than in the laser group. LLLT was suggested as an alternative when steroids cannot be used.

Across 120 adults with sore, eroded oral lichen planus on the tongue or inside of the cheeks, a 2015 randomized controlled trial in Turkey compared low-level laser therapy (LLLT), ozone treatment, a steroid ointment, and a placebo ointment. The 56 men and 64 women, aged 28 to 55 (average 42.6), had patches of 3 cm or less, and LLLT used 808 nm light at 10 mW/cm² and 1.5 J/cm² over 7 days. According to the trial, symptoms eased with LLLT, ozone, and steroid alike, but the visible signs improved significantly only with ozone and steroid, which also scored higher on the trial's effectiveness index. The authors concluded that ozone and steroid were more effective than LLLT.

This 2013 pilot clinical trial from Italy combined low-level laser therapy (LLLT) with professional gum cleaning in 6 patients whose oral lichen planus on the gums had not responded to standard steroid treatment. LLLT used a 980 nm GaAlAs diode laser alongside the cleaning, with severity and pain scores recorded before and after. Pain scores fell significantly, and 5 of the 6 patients reported that their symptoms improved within 2 weeks. The visible severity of the patches also eased in the first 2 weeks, but not by a statistically significant amount. The authors described the combination as a feasible, side-effect-free option that worked faster than earlier laser protocols.