PhotoBioModulation An Updated Literature Review with Relevant Case Report

Nov 30 / Dr. Kevin NG and Dato' Dr. How Kim Chuan
Orthodontic tooth movements cause pain and discomfort. It also takes a long time to complete; the average treatment time is usually about 2-3 years to achieve satisfactory results. These factors have been hindering patients from seeking treatment. To avoid long-term suffering and to enhance patient cooperation and compliance, PBM (Photo Bio Modulation) is considered for the possibility of shortening treatment times. Although different clinicians hold different views regarding the application of PBM to influence orthodontic effects and outcomes, one case is reported here with satisfactory patient feedback and acceptable clinical outcome. The PBM device used contained 42 LED cores that produced 828nm wavelength light and stimulated for 4 minutes on each arch daily. It was found that there was a 50% reduction in treatment time for the whole Invisalign treatment course, with no pain felt and improved results.
The PBM Device

The bite plane device consists of 42 LED cores and the power input is 2.1 volts. The current of each LED core is 30 mA. The LED cores produce a wavelength of 855 nm to stimulate the target sites. Energy absorbed after 4 minutes per arch is 248 joules. The manufacturer claims that the science of Photo Bio Modulation (PBM) mechanism in orthodontics is to enhance the biology of the treatment area and improve the healing of bone and soft tissues, further enhancing tooth movement.
Case Report

Male patient CST, age 20 presented with Class I Molars, moderate anterior crowding of upper and lower arches. Rotation of 12, 23, 33 and 43. There was lower mid-line shift to left about 2mm. Overjet 1mm, Overbite 3 mm. Patient does not wish extractions and requested shortest possible time to finish the treatment. ITero scanning were performed, and arches expansions were designed to improve the arches form to create spaces for alignments. The numbers of aligners were 45 sets and treatment time was suggested about 1 year with 1 aligner each week. PBM lights were prescribed, and 2 aligners were used for each week.

The 45 aligners should be finished wearing by 23 weeks. The PBM device were applied for 4 min daily on each arch and patient was advised to return to clinic monthly to check and ensure fittings. Patient was also informed to record the degree of pain/discomfort monthly in the given form during aligner treatment. The feedback pain scores were 2-3 for the whole period. OPG were taken before and after treatment and found there were no root absorption occurred.

Discussion


Surgical corticotomy were used to accelerate orthodontic tooth movement before the application of PBM. However, the post-operative pain and complications cause concerns to patient. In 2013, Kau assessed 73 patients and 17 controls who were fitted with traditional orthodontic brackets and wires, and treated with 850 nm wavelength Near-Infrared light with a power density of 60 mW/cm² for 20-30 min per day. He observed Photobiomodulation achieved clinically significant accelerated tooth movements as compared to the control group. Lao proposed PBM is a non-invasive stimulation of the dentoalveolar complex with ATP production at the mitochondrial cells. Due to increased levels of metabolic activity, ATP is increased at a localized level and causes remodeling processes. Infrared light doubles Cytochrome oxidase levels which mediates ATP production. Higher ATP availability accelerates cells' turnover, resulting in a faster remodeling process and tooth movement. An average of 1.12 mm movement per week for the PBM group was observed compared to 0.49 mm in the control group.

The mechanism of photobiomodulation is due to certain biologically active wavelengths elicited by the LED cores that have therapeutic effects at cellular levels. The photon source after LED produced favorable effects both in animal studies and recently in human clinical studies. The early clinical trials started with pain control, tooth movement acceleration, and increased bone remodeling and quality. Recently, this therapeutic technology had success reports on the improvement in mini-screw stability, TMD disorders, root resorption, bone consolidation during maxillary expansion, and distraction osteogenesis. It is easy to operate and non-invasive, leading to a wide clinical use. Shan et al. in 2021 found that PBM had a promising effect on post-orthodontic root resorption rehabilitation. Reis et al. in 2021 suggested that during orthodontic tooth movement, cytokines were released in the gingival crevice affecting bone remodeling. PBM stimulations increased the levels of IL-1β, IL-8, OPN, and PGE2, with LLLT statistically related to an increase in IL-1β levels.

Brawn et al. in 2017 investigated the use of Biolux light-emitting diode phototherapy daily for 21 days on extracted sockets with HA grafting. They found accelerated bone healing in the phototherapy-treated HA socket graft, which may provide faster implant osseointegration and healing compared to the control group. Ekizer et al. in 2016 found PBM had the potential to accelerate tooth movement and had a positive effect on mini-screws, and these results were supported by AlShahrani et al. in 2019, who found a statistically significant difference between PBM therapy and the non-stimulated group with a mean difference of 0.59. It was proposed that the action of LPT IL-1B attracts leukocytes and stimulates fibroblasts, endothelial cells, and osteoclasts, causing these effects.

In another study, Ozturk in 2020 found that PBM applications showed inhibitory and reparative effects on OIIRR by modulating the RANKL and COX-2 expression levels. Resorption lacunae volume, number of resorption lacunae, and percentage of the resorption lacunae decreased with PBM applications compared to the positive control groups. They also found that the effects of the different wavelengths were similar.

Sfondrini et al. in 2020 studied the pain experience on subjects with banded maxillary first molars. Each molar received one session of PBM treatment on two buccal and two palatal points. In the trial group, PBM treatment showed to be an alternative to decrease pain sensation compared to the control group. Reis et al. in 2021 reiterated that during orthodontic tooth movement, cytokines were released in the gingival crevice affecting bone remodeling, with PBM stimulations increasing levels of IL-1β, IL-8, OPN, and PGE2.

Abellán in 2021 used an intraoral scanner and CBCT to study molar intrusion using mini-screws as anchorage. They found the technique effective for accurately monitoring the intrusion distance. CBCT records allowed volumetric evaluation of the root resorption process, finding less resorption in the PBM group. They suggested that the application of PBM may provide better periodontal records and lower progression of root resorption at the expense of a slightly lower intrusion distance and velocity.

Finally, Caccianiga in 2022 reported on 30 patients treated with rapid palatal expansion, noting significantly lower pain in the experimental group. PBM was used in orthodontics together with anchoring TAD micro-screws for stability. After 60 days post-treatment, significantly higher stability was noted in the PBM group, leading the authors to conclude that the application of the 808 nm diode laser increased micro-implant stability clinically and decreased pain felt by patients.

Conclusions


With the updated information suggested above, it is possible to apply PBM safely to assist orthodontic patients and even to improve treatment time and outcomes for patients who have received implant treatments. The findings here suggest that intraoral PBM could be used to decrease alignment treatment time, pain/discomfort, and quality of bone formation that could promote bone healing and osseointegration of dental implants. However, due to its research limitations, further extensive research by multi-centered, randomized clinical trials is suggested.