Photobiomodulation in Oral Medicine

Comparison of the postoperative effect of low laser therapy and platelet rich fibrin on mandibular third molar surgery: a randomized study

BACKGROUND

This study investigates the postoperative benefits of low-level laser therapy (LLLT) and platelet-rich fibrin (PRF) in enhancing patient comfort and reducing complications after mandibular third molar extractions.

METHODS

Sixty patients with vertically impacted mandibular third molars were randomly assigned to one control and three test groups (n = 15 each). In Group 1, PRF was applied to the socket post-extraction. In Group 2, PRF was combined with LLLT (B-Cure Dental Laser, 808 nm wavelength, 4 J/cm² energy density, continuous wave) applied extra-orally for three days post-surgery. Group 3 received LLLT alone. Group 4 (control group) underwent traditional osteotomy without additional treatments. All patients were prescribed 875/125 mg amoxicillin/clavulanic acid twice daily for five days.

RESULTS

Postoperative parameters such as pain, swelling, analgesic use, and trismus were assessed on days 1, 2, 3, and 7. Significant improvements in pain, swelling, and trismus were observed in Groups 2 and 3 compared to the control (p < 0.001). Swelling was also significantly reduced in Group 1 compared to the control.

CONCLUSIONS

The study demonstrated favorable clinical outcomes in the LLLT and PRF groups, suggesting that both treatments could be promising strategies for improving postoperative recovery in terms of comfort and reduced complications.

TRIAL REGISTIRATION

Clinicaltrials.gov ID: NCT06262945. The trial was first registered on 16/02/2024. Retrospectively registered.

Current trends and available evidence on low-level laser therapy for osteoradionecrosis: A scoping review

BACKGROUND

This scoping review explored current trends and available evidence in Low-Level Laser Therapy (LLLT) in the treatment and prevention of osteoradionecrosis.

METHODS

The search strategy was conducted in MEDLINE/PubMed, EMBASE, Web of Science, and grey literature on January 15, 2024, without language or time restrictions.

RESULTS

19 studies were included. The application of LLLT protocols was 58 % for therapeutic use, 21 % for preventive use, and 21 % for a combination of both. Regarding the use of antimicrobial photodynamic therapy (aPDT), 41 % of the studies employed this technique, which utilized methylene blue as the photosensitizer. For treatments associated with photobiomodulation, 57 % reported pharmacological treatment, 29 % surgical treatment, 11 % prescribed chlorhexidine mouthwashes, and 4 % other therapies. In vivo studies used diode lasers emitting low incident power densities in the near-infrared wavelength (67 %) at 780 to 904 nm. In comparison, case reports also used diode lasers emitting low incident power densities in the red and near-infrared wavelength (64 %) at 660 to 904 nm. The continuous emission mode was utilized in 83 % of in vivo studies and 17 % of the case reports. None of the studies included in this review reported all laser parameters.

CONCLUSIONS

In general, studies suggested that LLLT can be used for therapeutic and preventive applications in the management of osteoradionecrosis. However, clinical studies are case reports and the variability in laser parameters across the included studies poses challenges for establishing standardized treatment protocols. The lack of comprehensive data on laser parameters underscores the need for future research to focus on standardizing LLLT protocols and conducting well-designed, large-scale clinical trials. This approach will help to better evaluate the effectiveness of LLLT and potentially integrate it more reliably into clinical practice.

Piezoelectric Surgery, Er:YAG Laser Surgery and Nd:YAG Laser Photobiomodulation: A Combined Approach to Treat Medication-Related Osteonecrosis of the Jaws (MRONJ)

Medication-related osteonecrosis of the jaw (MRONJ) is a drug complication that can occur in patients taking antiresorptive or antiangiogenic drugs. Although it is a well-documented disease, there is no widely accepted treatment. However, several therapeutic approaches have been proposed. The surgical approach in many advanced cases appears inevitable; however, the results are not yet defined and predictable. This study aimed to propose a combined surgical approach with a piezoelectric device and laser (Er:YAG for bone ablation and Nd:YAG laser for photobiomodulation) in a young patient with breast cancer and bone metastasis under denosumab treatment, affected by spontaneous stage 3 MRONJ with maxillary sinus involvement. The patient under study reported no post-operative discomfort, with painkiller intake limited to the day after surgery. Total mucosal healing was observed without recurrences for more than 4 years after surgery. According to the results of our preliminary study, a combined surgical approach using a piezoelectric device and laser therapy is effective in managing patients affected by MRONJ, leveraging the clinical and biological advantages of these different techniques.

Comparative efficacy of photobiomodulation on osseointegration in dental implants: A systematic review and meta-analysis

AIM

This study aimed to assess the effectiveness of photobiomodulation therapy (PBM) in enhancing bone integration with dental implants.

METHOD

PubMed, ScienceDirect, the Cochrane Library, Scopus, and Google Scholar were searched. Studies assessing PBM effectiveness with defined intervention/control groups were included, while those lacking specified laser types, involving severe maxillofacial defects or surgery, and not reporting outcomes related to dental implant osseointegration post-PBM therapy were excluded. The studies' risk of bias was assessed using Robvis for randomized controlled trials (RCTs) and ROBINS-I for non-RCTs. The meta-analysis was conducted utilizing a random-effects model at a significance level of 0.01.

RESULTS

The study reviewed 26 papers involving 571 patients undergoing dental implant procedures with PBM/Low-Level Laser Therapy (LLLT) or placebo/control. Implant stability quotients (ISQ) analysis showed a non-significant difference (p = 0.06, mean difference: 1.02, 95 % CI: 0.28 to 1.75, I2=28 %), while the Periotest method indicated significant improvement in stability (p < 0.01, mean difference: -0.51, 95 % CI: -0.78 to -0.24, I2=71 %). PBM resulted in a significant bone density increase (p < 0.01, mean difference: 26, 95 % CI: 6.93 to 45.06, I2=91 %), but marginal bone loss showed no significant difference (p = 0.11, mean difference: 0.00, 95 % CI: -0.06 to 0.05, I2=45 %). Implant survival rate did not significantly differ (p = 0.73, mean difference: 1.56, 95 % CI: 0.38 to 6.46, I2=0 %). Most studies raised concerns regarding randomization.

CONCLUSION

PBM could improve implant stability, as assessed with Periotest, and increase bone density, enhancing osseointegration. However, implant stability assessed with ISQ, marginal bone loss, and implant survival rate were comparable between the study groups.

Osteonecrosis of the Jaws Associated with Herpes Zoster Infection: A Systematic Review and a Rare Case Report

The investigation's goal was to obtain further knowledge about the connection between Herpes Zoster infection and dentistry therapy for the osteonecrosis of the jaws, combining the review with a case report relevant to the purpose. It is important to study this association because it is a possible additional factor to be considered in the causes of the osteonecrosis of the jaws. We limited our search to English-language papers published between 1 January 2004 and 7 June 2024 in PubMed, Scopus, and Web of Science that were relevant to our topic. In the search approach, the Boolean keywords "Herpes Zoster AND osteonecros*" were used. Results: This study analyzed 148 papers from Web of Science, PubMed, and Scopus, resulting in 95 articles after removing duplicates. Of these, 49 were removed because they were off topic, and 46 were confirmed. This study includes a qualitative analysis of the final 12 articles, removing 34 articles that were off topic. The literature highlights severe oral complications from Herpes Zoster reactivation, emphasizing the need for early diagnosis, comprehensive management, and multidisciplinary care. Treatment strategies include antiviral therapy, pain management, surgical debridement, and antibiotics. Immunocompromised individuals require vigilant monitoring and balanced immunosuppressive therapy. Further research is needed to enhance therapeutic approaches.

High-frequency low-intensity semiconductor laser irradiation enhances osteogenic differentiation of human cementoblast lineage cells

PURPOSE

Laser irradiation activates a range of cellular processes in the periodontal components and promotes tissue repair. However, its effect on osteogenic differentiation of human cementoblast lineage cells remains unclear. This study aimed to examine the effects of high-frequency semiconductor laser irradiation on the osteogenic differentiation of human cementoblast lineage (HCEM) cells.

METHODS

HCEM cells were cultured to reach 80% confluence and irradiated with a gallium-aluminum-arsenide (Ga-Al-As) semiconductor laser with a pulse width of 200 ns and wavelength of 910 at a dose of 0-2.0 J/cm2. The outcomes were assessed by analyzing the mRNA levels of alkaline phosphatase (ALP), runt-related transcription factor 2 (RUNX2), and type I collagen (COLL1) using real-time polymerase chain reaction (PCR) analysis 24 h after laser irradiation. Cell mineralization was evaluated using ALP activity, calcium deposition, and Alizarin Red staining.

RESULTS

The laser-irradiated HCEM cells showed significantly enhanced gene expression levels of ALP, RUNX2, and COLL1 as well as ALP activity and calcium concentration in the culture medium compared with the non-irradiated cells. In addition, enhanced calcification deposits were confirmed in the laser-irradiated group compared with the non-irradiated group at 21 and 28 days after the induction of osteogenic differentiation.

CONCLUSION

High-frequency semiconductor laser irradiation enhances the osteogenic differentiation potential of cultured HCEM cells, underscoring its potential utility for periodontal tissue regeneration.

Photobiomodulation and vitamin B treatment alleviate both thermal and mechanical orofacial pain in rats

PURPOSE

The present study investigates the efficacy of Photobiomodulation (PBM) and Vitamin B Complex (VBC) to relieve pain, both in separately and combined (PBM and VBC).

METHODS

Rats with chronic constriction injury of the right infraorbital nerve (CCI-IoN) or Sham surgery were used. PBM was administered at a wavelength of 904 nm and energy density of 6.23 J/cm2 and VBC (containing B1, B6 and B12) subcutaneously, both separately and combined. Behavioral tests were performed to assess mechanical and thermal hypersensitivity before and after CCI and after PBM, VBC, or PBM + VBC. The expression of inflammatory proteins in the trigeminal ganglion and the immunohistochemical alterations of Periaqueductal Gray (PAG) astrocytes and microglia were examined following CCI and treatments.

RESULTS

All testeds treatments reversed the painful behavior. The decrease in pain was accompanied by a decrease of Glial Fibrillary Acidic Protein (GFAP), a specific astrocytic marker, and Ionized calcium-binding adaptor molecule 1 (Iba-1), a marker of microglia, and decreased expression of Transient Receptor Potential Vanilloid 1 (TRPV1), Substance P, and Calcitonin Gene-Related Peptide (CGRP) induced by CCI-IoN in PAG and Trigeminal ganglion. Furthermore, both treatments showed a higher expression of Cannabinoid-type 1 (CB1) receptor in the trigeminal ganglion compared to CCI-IoN rats. Our results show that no difference was observed between groups.

CONCLUSION

We showed that PBM or VBC regulates neuroinflammation and reduces inflammatory protein expression. However, the combination of PBM and VBC did not enhance the effectiveness of both therapies alone.

The effect of different treatment protocols with diode laser on regeneration in axonetmesis ınjuries of the ınferior alveolar nerve: an animal study

The inferior alveolar nerve can be damaged during dental procedures, leading to symptoms, such as tingling, numbness, and reduced quality of life. Recovery depends on factors such as medications, surgery, and photobiomodulation therapy. Photobiomodulation therapy has shown the potential to improve nerve function and reduce regeneration time; however, there is no standard treatment protocol yet. This study aimed to examine the effect of diode lasers on nerve regeneration in patients with axonetmesis injuries. In this experiment on animals, Wistar rats' damaged sensory systems were treated with lasers to restore them. Animals were randomly divided into six groups: a sham group, a control group, and four laser treatment groups(1st group: performed every day, 10 sessions; 2nd group: performed every 2 days, 10 sessions; 3rd group: performed every day, 20 sessions; and 4th group: performed every 2 days, 20 sessions). Sensory function was determined using the Semmes-Weinstein monofilament test, which was repeated after the surgical procedure. The results showed that the 20-session group had the best improvement, most closely resembling the group without sensory test damage. The histomorphometric results showed that the number of axons was significantly lower in the group that received 10 daily sessions and in the control group than in the undamaged nerve. Axon diameter was lower in all groups than in the sham group. In conclusion, the remarkable aspect of this study is that consecutive-day 20-session laser treatment showed better improvement than the over-the-day 20-session treatment protocol.

Photobiomodulation-Based Synergic Effects of Pt-Coated TiO2 Nanotubes and 850 nm Near-Infrared Irradiation on the Osseointegration Enhancement: In Vitro and In Vivo Evaluation

Photobiomodulation (PBM) therapy is known to have the potential to improve bone regeneration after implant surgery. However, the combinatory effect of the nanotextured implant and PBM therapy on osseointegration has not yet been proved. This study evaluated the photobiomodulation-based synergistic effects of Pt-coated titania nanotubes (Pt-TiO₂ NT) and 850 nm near-infrared (NIR) light on osteogenic performance in vitro and in vivo. The FE-SEM and the diffuse UV-Vis-NIR spectrophotometer were used to perform the surface characterization. The live-dead, MTT, ALP, and AR assays were tested to perform in vitro tests. The removal torque testing, the 3D-micro CT, and the histological analysis were used to conduct in vivo tests. The live-dead and MTT assay resulted in Pt-TiO₂ NTs being biocompatible. The ALP activity and AR assays demonstrated that the combination of Pt-TiO₂ NT and NIR irradiation significantly enhanced osteogenic functionality (p < 0.05). The results of in vivo test, employing the removal torque testing, the 3D-micro CT, and histological analysis, showed overall improved outcomes; however, no significant difference was observed between the control and experimental groups (p > 0.05). Therefore, we confirmed the possibility of the combination of Pt-TiO₂ NT and NIR light as a promising technology for implant surgery in dentistry.

Photobiomodulation Therapy and Pulp-Regenerative Endodontics: A Narrative Review

Regenerative endodontic procedures (REPs) were used to recover the dental pulp’s vitality in order to avoid the undesirable outcomes of conventional endodontic treatment and to promote dentinal formation, especially for immature permanent teeth. Photobiomodulation therapy (PBMT) exhibits photobiological and photochemical effects for improving the root canal’s environmental conditions by compensating for oxidative stress and increasing the blood supply to implanted stem cells and improving their survival. Basic research has revealed that PBMT can modulate human dental pulp stem cells’ (hDPSCs) differentiation, proliferation, and activity, and subsequent tissue activation. However, many unclear points still remain regarding the mechanisms of action induced by PBMT in REPs. Therefore, in this review, we present the applications of laser and PBMT irradiation to the procedures of REPs and in endodontics. In addition, the effects of PBMT on the regenerative processes of hDPSCs are reviewed from biochemical and cytological perspectives on the basis of the available literature. Furthermore, we consider the feasibility of treatment in which PBMT irradiation is applied to stem cells, including dental pulp stem cells, and we discuss research that has reported on its effect.

Oral microbiota dysbiosis accelerates the development and onset of mucositis and oral ulcers

With the rapid development of metagenomic high-throughput sequencing technology, more and more oral mucosal diseases have been proven to be associated with oral microbiota shifts or dysbiosis. The commensal oral microbiota can greatly influence the colonization and resistance of pathogenic microorganisms and induce primary immunity. Once dysbiosis occurs, it can lead to damage to oral mucosal epithelial defense, thus accelerating the pathological process. As common oral mucosal diseases, oral mucositis and ulcers seriously affect patients' prognosis and quality of life. However, from the microbiota perspective, the etiologies, specific alterations of oral flora, pathogenic changes, and therapy for microbiota are still lacking in a comprehensive overview. This review makes a retrospective summary of the above problems, dialectically based on oral microecology, to provide a new perspective on oral mucosal lesions management and aims at improving patients' quality of life.

Desquamative Gingivitis in the Context of Autoimmune Bullous Dermatoses and Lichen Planus-Challenges in the Diagnosis and Treatment

Desquamative gingivitis (DG) is a clinical term that describes erythema, desquamation and erosions of the gingiva, of various etiologies. Although the clinical aspect is not specific for a certain disease, an accurate diagnosis of the underlying disorder is necessary because the disease course, prognosis and treatment vary according to the cause. DG may inflict significant oral discomfort, which is why patients typically present to the dentist for a first consultation, rendering it important for these specialists to be informed about this condition. Our paper aims to review the ethiopatogenesis and diagnostic approach of DG, focusing on the most common underlying disorders (autoimmune bullous dermatoses and lichen planus) and on the management of these patients. Potential etiological agents leading to an inflammatory immune response in the oral mucosa and DG appearance include genetic predisposition, metabolic, neuropsychiatric, infectious factors, medication, dental materials, graft-versus-host reaction and autoimmunity. A thorough anamnesis, a careful clinical examination, paraclinical explorations including histopathological exam and direct immunofluorescence are necessary to formulate an appropriate diagnosis. Proper and prompt management of these patients lead to a better prognosis and improved quality of life, and must include management in the dental office with sanitizing the oral cavity, instructing the patient for rigorous oral hygiene, periodic follow-up for bacterial plaque detection and removal, as well as topical and systemic therapy depending on the underlying disorder, based on treatment algorithms. A multidisciplinary approach for the diagnosis and follow-up of DG in the context of pemphigus vulgaris, bullous pemphigoid, cicatricial pemhigoid or lichen planus is necessary, including consultations with dermatologists, oral medicine specialists and dentists.

Response of osteoblastic cells to low-level laser treatment: a systematic review

Low-level laser therapy (LLLT)-induced photobiomodulation (PBM) stimulates bone tissue regeneration by inducing osteoblast differentiation and mitochondrial activation. However, the role of reactive oxygen species (ROS) in this process remains controversial. The aim of this systematic review was to collect and analyze the available literature on the cellular and molecular effects of LLLT on osteoblasts and the role of ROS in this process. A search was conducted in PubMed, ScienceDirect, Scopus, and Web of Science. Studies published in English over the past 15 years were selected. Fourteen articles were included with moderate (n = 9) and low risk of bias (n = 5). Thirteen studies reported the use of diode lasers with wavelengths (λ) between 635 and 980 nm. One study used an Nd:YAG laser (λ1064 nm). The most commonly used λ values were 808 and 635 nm. The energy densities ranged from 0.378 to 78.75 J/cm², and irradiation times from 1.5 to 300 s. Most studies found increases in proliferation, ATP synthesis, mitochondrial activity, and osteoblastic differentiation related to moderate and dose-dependent increases in intracellular ROS levels. Only two studies reported no significant changes. The data presented heterogeneity owing to the variety of LLLT protocols. Although several studies have shown a positive role of ROS in the induction of proliferation, migration, and differentiation of different cell types, further research is required to determine the specific role of ROS in the osteoblastic cell response and the molecular mechanisms involved in triggering previously reported cellular events.

Laser oromaxillofacial photobiomodulation therapy: molecular mechanisms, outcomes and considerations

Tweetable abstract Photobiomodulation therapy is largely characterized as a safe therapeutic model that can modulate the activity of inflammatory and immune biomarkers while facilitating a metabolic response that can regenerate damaged tissue.

Innovative Concepts and Recent Breakthrough for Engineered Graft and Constructs for Bone Regeneration: A Literature Systematic Review

BACKGROUND

For decades, regenerative medicine and dentistry have been improved with new therapies and innovative clinical protocols. The aim of the present investigation was to evaluate through a critical review the recent innovations in the field of bone regeneration with a focus on the healing potentials and clinical protocols of bone substitutes combined with engineered constructs, growth factors and photobiomodulation applications.

METHODS

A Boolean systematic search was conducted by PubMed/Medline, PubMed/Central, Web of Science and Google scholar databases according to the PRISMA guidelines.

RESULTS

After the initial screening, a total of 304 papers were considered eligible for the qualitative synthesis. The articles included were categorized according to the main topics: alloplastic bone substitutes, autologous teeth derived substitutes, xenografts, platelet-derived concentrates, laser therapy, microbiota and bone metabolism and mesenchymal cells construct.

CONCLUSIONS

The effectiveness of the present investigation showed that the use of biocompatible and bio-resorbable bone substitutes are related to the high-predictability of the bone regeneration protocols, while the oral microbiota and systemic health of the patient produce a clinical advantage for the long-term success of the regeneration procedures and implant-supported restorations. The use of growth factors is able to reduce the co-morbidity of the regenerative procedure ameliorating the post-operative healing phase. The LLLT is an adjuvant protocol to improve the soft and hard tissues response for bone regeneration treatment protocols.

Tumor radiosensitization by photobiomodulation

PURPOSE

To investigate the safety of photobiomodulation therapy (PBM) in tumors and its potential as a radiosensitizer when combined with radiotherapy.

METHODS

We have performed in vitro experiments in A431 cells to assess proliferation and cell cycle after PBM, as well as clonogenic assay and H2AX-gamma immunolabeling to quantify double strand breaks after the combination of PBM and radiation. In vivo experiments in xenografts included Kaplan-Meier survival analysis, optical coherence tomography (OCT) and histological analysis.

RESULTS

PBM did not induce proliferation in vitro, but increased the G2/M fraction by 27% 24h after illumination, resulting in an enhancement of 30% in radiation effect in the clonogenic assay. The median survival of the PBM-RT group increased by 4 days and the hazard ratio was 0.417 (CI 95%: 0.173-1.006) when compared to radiation alone. OCT analysis over time demonstrated that PBM increases tumor necrosis due to radiation, and histological analysis showed that illumination increased cell differentiation and angiogenesis, which may play a role in the synergetic effect of PBM and radiation.

CONCLUSION

PBM technique may be one of the most appropriate approaches for radiosensitizing tumors while protecting normal tissue because of its low cost and low training requirements for staff.

Photobiomodulation Therapy vs. Corticosteroid for the Management of Erosive/Ulcerative and Painful Oral Lichen Planus. Assessment of Success Rate during One-Year Follow-Up: A Retrospective Study

Photobiomodulation (PBM) therapy is a promising approach for the management of inflammatory conditions and autoimmune lesions, such as oral lichen planus (OLP). The aim of this retrospective study was to assess the effectiveness of PBM in the management of painful and erosive/ulcerative OLP and to compare it with the standard of care that is the topical application of corticosteroids. 96 patients were included with erosive and painful OLP. 48 patients received PBM therapy and 48 received corticosteroids. Data was collected retrospectively on pain using the visual analogue scale; clinical aspects of lesions were assessed with the REU score, and the recurrence rate was noted. One session of PBM therapy with a helium-neon red light (635 nm) was carried out every 48 h for 6 weeks. Treatments were mainly made in contact mode, using a fiber with a diameter of 600 µm (0.6 mm). The output power of the laser beam was calibrated by a power meter. A delivered power of 0.1 W was used for 40 s in a continuous wave (CW), corresponding to a delivered energy of 4 J. The delivered energy density related to the fiber diameter was 1415 J/cm². Each treated point was considered as 1 cm² of diameter. PBM therapy within these parameters was carried out on each point until the totality of the lesion was covered, including the non-erosive OLP area. Furthermore, healthy mucosa within 5 mm of the lesion was also irradiated with the same conditions. This PBM treatment was performed during 6 consecutive weeks. The topical corticosteroid treatment consisted of&nbsp;cortisone application to cover the OLP 3 times/day for 6 weeks. Follow-up was made at 6 weeks and at 3, 6 and 12 months. After 6 weeks, both groups showed complete absence of pain, and a complete disappearance of ulcerative/erosive areas. No significant difference was found for both groups concerning the recurrence rate of erosive OLP during the follow-up period; values were 0% at 6 weeks for both groups and 79% and 87.5% for the corticosteroid and PBM group, respectively, at 12 months of follow-up. PBM is effective for managing OLP and is significantly similar to topical corticosteroids without any need for the use of medication and with no reported side effects.

Effects of low-level light therapy on xerostomia related to hyposalivation: a systematic review and meta-analysis of clinical trials

Hyposalivation is a condition represented by a reduced salivary flow and may include symptoms such as mouth dryness (xerostomia), loss of taste, pain, dysphagia, and dysphonia, all of which greatly affect an individual's quality of life.The aim of the present study was to systematically review the effects of low-level light therapy irradiation (photobiomodulation) on salivary gland function in patients with hyposalivation.The main question of the systematic review was: "Does low-level light irradiation therapy of the salivary glands affect salivary flow rate or indicators of salivary function (ion and protein concentrations) in patients with xerostomia or hyposalivation?" The question was based on the PICO (participant, intervention, control, outcome) principle and followed the PRISMA guidelines. Databases were explored and papers published between the years 1997 and 2020 were reviewed for the following Mesh-term keywords and their corresponding entry terms in different combinations: "Low-level light therapy," "Xerostomia," "Saliva," "Salivary glands," "Salivation."The initial sample consisted of 220 articles. Of those, 47 articles were used for full-text analysis and 18 were used for a systematic review, 14 were used in meta-analysis. According to their individual quality, most articles were classified as high quality of evidence according to the GRADE score. Meta-analysis of the evidence observed increase of unstimulated salivary flow 0.51 SMD compared to placebo (95% CI: 0.16-0.86), I² = 50%, p = 0.005.The findings of our review revealed evidence of a beneficial effect of photobiomodulation therapy on salivary gland function. The therapy alleviates xerostomia and hyposalivation. However, these effects are reported short term only and did not induce lasting effects of photobiomodulation therapy on patients' quality of life.

Photobiomodulation effects on photodynamic therapy in HNSCC cell lines

A combination of metabolic modifications by light stimulus and photodynamic action is very attractive. Photobiomodulation therapy (PBMT) comprehends a vast range of applications and has been shown to be suitable to ease morbidities caused by chemotherapy and radiation, such as mucositis and dermatitis. The current study investigates the effects of near-infrared PBMT combined with porphyrin-based photodynamic therapy (PDT) in squamous cell carcinoma cell lines SCC-25 and SCC-4. The aim is to evaluate the potential of this combination to improve PDT outcome by increasing cell toxicity. Many techniques were used to verify the combined effect. Photobiomodulation (PBM) enhanced PDT action in SCC-25 cells by increasing photosensitizer (PS) uptake and production of reactive oxygen species (ROS). The equivalent was not seen in SCC-4 cells compared to the PDT only group. We believe these effects are strongly related to the interval of application between PBMT, PS incubation and PDT. Additionally, the effect of ascorbic acid on preventing PBM effects in PDT shows that ROS play an important role in the early mechanisms of PBM-PDT. Therefore, we believe PBM-PDT combination is worth exploring, for its benefit-cost ratio and simple protocols, along with the possibility of improvement in treatment resuts.

The Value of Photo Biological Regulation Based on Nano Semiconductor Laser Technology in the Treatment of Hypertension Fundus Disease

With the development of nanometer semiconductor laser technology, due to the wide range of photobiological regulation and non-invasive advantages, it is widely used in clinical research, including reducing pain, accelerating wound healing, nerve injury repair and regeneration. Increase tissue blood flow, improve anxiety and depression, and treat Parkinson's and retinal diseases. However, in many studies, the role of photobiological regulation is still controversial. There are two main problems, one is that the mechanism of photo biological regulation is not fully understood, and the other is that the specific parameters are not uniform in different treatments, such as wavelength density, power density, pulse, treatment timing, and number of treatments. In this paper, through the second question, the parameters of low-energy near-infrared light (810 nm semiconductor laser) in the treatment of fundus diseases are the main research objects. Based on understanding the parameters of low-energy lasers, cyan blue is irradiated with different energy near-infrared light. Data analysis of the actual energy obtained after the retina of the rabbit and observation and research on the cell morphology of each layer of the retina, to obtain relatively safe treatment parameters for the retina, provide theoretical data for near-infrared light in the treatment of clinical fundus disease, and make it safer to use in clinical treatment.