Effect of laser (λ 660 nm) and LED (λ 630 nm) photobiomodulation on formocresol-induced oral ulcers: a clinical and histological study on rodents

The effect of biopolymer gel derived from sugarcane on healing of traumatic oral ulcers: an experimental study

PURPOSE

The extracellular polysaccharide (EPS) is produced by the bacterium Zoogloea sp. and plays a positive role in tissue repair. The purpose of this study was to clinically and histologically compare the effects of EPS in the healing of traumatic oral ulcers in rats with the effects of triamcinolone.

METHODS

Ulcers were induced in the oral mucous of 45 male Wistar rats, divided into three groups: control group, treated with triamcinolone, and treated with biopolymer gel. In the clinical evaluation, we considered the weight variation of the animals and the size of the lesion area, at baseline and on treatment days 1, 3 and 7. The histological parameters evaluated were the type and intensity of the inflammatory infiltration, the presence of necrosis and foreign body granuloma and the degree of re-epithelialization of the lesion.

RESULTS

The reduction of the lesion area was greater in the animals treated with EPS, with no difference in the intensity of the inflammatory infiltration between the groups on days 3 and 7 of treatment.

CONCLUSIONS

The results suggest that topical application of EPS in traumatic oral ulcers of rats promotes faster repair than triamcinolone ointment, without increasing the intensity of inflammatory infiltration under the lesion.

Tumor necrosis factor alpha (TNF-α) blockage reduces acute inflammation and delayed wound healing in oral ulcer of rats

Oral traumatic ulcers (OTU) are common in dental routine, and the control of proinflammatory cytokines, such as the tumor necrosis factor-alpha (TNF-α), may interfere with OTU repair. Our aim was to evaluate the role of TNF-α in the healing process of OTU in rats. Wistar male rats were divided into six groups: a control-group (treated with 0.1 mL/kg of saline) and five groups treated with anti-TNF-α infliximab (INF) at 1, 3, 5, 7, and 10 mg/kg immediately before OTU production. The animals were weighed (day 0) and euthanized on days 1, 3, 7, 14 and 21 after ulceration. The ulcers were clinically measured, and the mucosa samples were histologically (scores 0-4), histochemically (collagen assay (pircrosirius)), histomorphometrically (cell counting), and immunohistochemically (TNF-α, α-smooth-muscle-actin (α-SMA), monocyte-chemoattractive-protein-1 (MCP-1), interleukin-8 (IL-8), and fibroblast-growth-factor (FGF)) analyzed. The Evans blue assay was used to measure the vascular permeability. ANOVA-1-2-way/Bonferroni, Kruskal-Wallis/Dunn, and correlation analyses were performed (GraphPad Prism 5.0, p < 0.05). High doses of INF reduced the OTU area (p = 0.043), body mass loss (p = 0.023), vascular permeability (p < 0.001), and reduced delayed histologic scores (p < 0.05), polymorphonuclear (p < 0.001) and mononuclear (p < 0.001) cells, blood vessel counting (p = 0.006), and total (p < 0.001), type-I (p = 0.018), and type-III (p < 0.001) collagen. INF treatment reduced TNF-α immunostaining and delayed MPC-1, FGF, and α-SMA expression, with little/none influence in IL-8 immunostaining. TNF-α blockage by INF reduced acute inflammation in OTU but delayed cell migration and wound healing.

Fluorescent light energy modulates healing in skin grafted mouse model

Skin grafting is often the only treatment for skin trauma when large areas of tissue are affected. This surgical intervention damages the deeper dermal layers of the skin with implications for wound healing and a risk of scar development. Photobiomodulation (PBM) therapy modulates biological processes in different tissues, with a positive effect on many cell types and pathways essential for wound healing. This study investigated the effect of fluorescent light energy (FLE) therapy, a novel type of PBM, on healing after skin grafting in a dermal fibrotic mouse model. Split-thickness human skin grafts were transplanted onto full-thickness excisional wounds on nude mice. Treated wounds were monitored, and excised xenografts were examined to assess healing and pathophysiological processes essential for developing chronic wounds or scarring. Results demonstrated that FLE treatment initially accelerated re-epithelialization and rete ridge formation, while later reduced neovascularization, collagen deposition, myofibroblast and mast cell accumulation, and connective tissue growth factor expression. While there was no visible difference in gross morphology, we found that FLE treatment promoted a balanced collagen remodeling. Collectively, these findings suggest that FLE has a conceivable effect at balancing healing after skin grafting, which reduces the risk of infections, chronic wound development, and fibrotic scarring.

Blue LED as a new treatment to vaginal stenosis due pelvic radiotherapy: Two case reports

BACKGROUND

Currently, the advancement cancer treatment technology improves overall survival, however, adverse events are still a challenge for health professional. Genitourinary syndrome of menopause and vaginal stenosis are conditions that impact the quality of life of patients undergoing radiotherapy. We present two such cases in patients with previous cervical and endometrial cancer. These conditions were handled with an innovative method using an energy-based device with blue light emitting diode for concomitant vaginal and vulvar irradiation. Positive impact in clinical findings, cytologic changes, and referred symptoms were documented.

CASE SUMMARY

One patient diagnosed with vaginal severe vaginal stenosis with previous cervix cancer treatment and other patient diagnosed with mild stenosis with severe dyspareunia and recent endometrium cancer treatment were considered for vulvovaginal treatment with weekly blue led device and closely evaluated with repeated validated questionnaires and cytological samples.

CONCLUSION

This innovative technique showed an improvement in all areas of the examiner's criteria, the cytological criteria, and most bothered symptoms.

Fluorescent Light Energy and Chronic Lesions: A Winning Association

Background:

Chronic ulcers represent a challenge for healthcare professionals and a large expense for national health care systems for their difficulty in achieving complete healing and for their high incidence of recurrence. With the progressive aging of the general population, the incidence of these injuries will only increase, further affecting the public health budget, hence the need to find new strategies for their management. The purpose of this study was to share the experience of the Complex Operational Unit of Plastic Surgery of the University Hospital of Padua with fluorescent light energy therapy, outlining its role in the treatment of chronic ulcers in the daily use outside the previous EUREKA study.

Methods:

In this case series study, we enrolled 15 patients with chronic ulcers of any etiology between January 2018 and July 2019 and we treated them using fluorescence light energy. We evaluated efficacy and safety endpoints reporting data in excel files completed by medical staff during the study.

Results:

The study confirms the effectiveness of fluorescent light energy inducing chronic ulcer healing, regardless of etiology, or at least preparing the lesions for a skin graft closure surgery. The system showed a low rate of complications established by patient adherence to treatment. Patients also reported a reduction in pain both at home and during outpatient dressings.

Conclusion:

Based on our experience, fluorescent light energy shows an excellent safety and efficacy profile in chronic ulcers no more responsive to traditional dressings and/or surgery.

Transoral Low-Level Laser Therapy Via a Cylindrical Device to Treat Oral Ulcers in a Rodent Model

BACKGROUND AND OBJECTIVE

Various clinical and animal studies have applied low-level laser therapy (LLLT) to treat oral ulcers. However, most previous studies applied lasers with small pinpoint irradiation, which required multiple laser irradiations to cover the complete extent of the ulcer. The objective of this study was to evaluate the effect of LLLT using a 635 nm diode laser via a transoral device to cover the whole lesion on oral ulcers in an animal model.

STUDY DESIGN/MATERIALS AND METHODS

An animal model of oral ulcers was developed with a 6 mm skin punch in the right buccal mucosa of Wistar rats (males, body weight 200-250 g). Three days after the mucosal injury, LLLT (spot size 2 cm² ) was conducted once a day for 5 days. Twenty-eight rats were randomly assigned into four groups according to energy density (control group, 5, 20, 75 J/cm² ). The size of the ulcers was measured and histologic analysis were performed ten days after the initial mucosal injury.

RESULTS

The mean size of the oral ulcers was significantly smaller in rats treated with an energy density of 20 J/cm² than that of any other group (control group or energy densities of 5 or 75 J/cm² ). The irradiation of oral ulcers with an energy density of 20 J/cm² accelerated the oral mucosa wound healing process and decreased inflammation and granulation tissue, resulting in good reepithelization. However, the histologic outcomes of rats irradiated with energy densities of 5 or 75 J/cm² were comparable with those of the control group.

CONCLUSION

LLLT using a 635 nm diode laser for oral ulcers with a transoral cylindrical device for wide light distribution may accelerate the wound healing process. LLLT with large-surface irradiation may be a substitute for previous LLLT for oral mucosal lesions conducted in a punctuate manner. Lasers Surg. Med. © 2019 Wiley Periodicals, Inc.

Polarized Polychromatic Noncoherent Light (Bioptron Light) as Adjunctive Treatment in Chronic Oral Mucosal Pain: A Pilot Study

Objective: Aim of this study was to assess the efficacy of polarized polychromatic noncoherent light (Bioptron light) in the treatment of chronic oral mucosal pain (COMP). Patients and methods: Twenty-two patients affected by COMP were treated with standardized pharmacological protocols in association with Bioptron light (90 W; light wavelength = 480-3400 nm; degree of polarization = 95%; specific power density = 40 mW/cm²; energy density = 2.4 J/cm). The outcome measures were intensity of pain [measured by visual analog scale (VAS) score] and signs reduction (measured by Eisen score) recorded at baseline (t₀), after 4 weeks (t₁), and after 8 weeks (t₂). Signs and symptoms scores were compared with those of a cohort of comparable patients selected from institutional medical record files. Results: Patients in pharmacological treatment associated with Bioptron showed a significant VAS score decrease at t₁ and t₂ (t₀ = 6.9, t₁ = 3.9, t₂ = 1.8, p < 0.05), whereas the patients in exclusive pharmacological treatment showed a significant VAS score improvement only at t₂. Comparing the VAS score at t₁ and t₂ in the two groups, a significant improvement was recorded in patients undergoing Bioptron adjunctive treatment (t₁ = 3.9 vs. 5.9; p < 0.05 and t₂ = 1.8 vs. 3.6; p < 0.05). In both groups Eisen score improved at t₁ and t₂, but in the Bioptron-treated patients the improvement was statistically better at t₁ (1.9 vs. 0.8; p < 0.05) and at t₂ (2.7 vs. 1.4; p < 0.05). Conclusions: In COMP patients, Bioptron use associated with pharmacological treatment allows a better and faster signs and symptoms reduction when compared with the exclusive pharmacological treatment. Further controlled studies are needed to establish the relative and absolute effectiveness of Bioptron in COMP management.

The Effect of Using Bone Marrow Mesenchymal Stem Cells Versus Platelet Rich Plasma on the Healing of Induced Oral Ulcer in Albino Rats

Background and Objectives

Oral ulceration is one of the most common debilitating condition that affects the oral cavity. In this study, the effect of locally injected platelet rich plasma (PRP) and bone marrow-derived mesenchymal stem cells (BMSCs) on the healing of oral ulcer was investigated.

Methods and Results

An ulcer was induced in buccal mucosa of rats by using 5mm biopsy punch followed by application of cotton swab soaked with formocresol for 60sec. The ulcer was left untreated in the control group, treated with intralesional injection of PRP, or isolated cultured BMSCs. Data were analyzed clinically, histologically and immunohistologically on day 3, 5, 7 and 10. BMSCs group showed smaller ulcer area throughout the whole experimental period than the other groups with complete resolution of the ulcer on day 10, unlike the control group. However, there was no significant difference with PRP, on day 5, 7 and 10, regarding clinical ulcer size. BMSCs group showed better histological results regarding the rate of epithelial cell migration, the number of inflammatory cells, thickness and organization of collagen fibres and the number of blood vessels, with complete re-epithelization on day 10. BMSCs group showed a greater number of anti-PCNA positive nuclei throughout the whole experimental period than the other groups except on day 5, PRP had higher mean numbers of anti-PCNA positive nuclei in both tissues.

Conclusions

Both PRP and BMSCs accelerate wound healing and enhance the quality of the healing tissue with the latter being slightly more effective and faster.

Photobiomodulation: lasers vs. light emitting diodes?

Photobiomodulation (PBM) is a treatment method based on research findings showing that irradiation with certain wavelengths of red or near-infrared light has been shown to produce a range of physiological effects in cells, tissues, animals and humans. Scientific research into PBM was initially started in the late 1960s by utilizing the newly invented (1960) lasers, and the therapy rapidly became known as "low-level laser therapy". It was mainly used for wound healing and reduction of pain and inflammation. Despite other light sources being available during the first 40 years of PBM research, lasers remained by far the most commonly employed device, and in fact, some authors insisted that lasers were essential to the therapeutic benefit. Collimated, coherent, highly monochromatic beams with the possibility of high power densities were considered preferable. However in recent years, non-coherent light sources such as light-emitting diodes (LEDs) and broad-band lamps have become common. Advantages of LEDs include no laser safety considerations, ease of home use, ability to irradiate a large area of tissue at once, possibility of wearable devices, and much lower cost per mW. LED photobiomodulation is here to stay.

Photobiomodulation: lasers vs. light emitting diodes?

Photobiomodulation (PBM) is a treatment method based on research findings showing that irradiation with certain wavelengths of red or near-infrared light has been shown to produce a range of physiological effects in cells, tissues, animals and humans. Scientific research into PBM was initially started in the late 1960s by utilizing the newly invented (1960) lasers, and the therapy rapidly became known as "low-level laser therapy". It was mainly used for wound healing and reduction of pain and inflammation. Despite other light sources being available during the first 40 years of PBM research, lasers remained by far the most commonly employed device, and in fact, some authors insisted that lasers were essential to the therapeutic benefit. Collimated, coherent, highly monochromatic beams with the possibility of high power densities were considered preferable. However in recent years, non-coherent light sources such as light-emitting diodes (LEDs) and broad-band lamps have become common. Advantages of LEDs include no laser safety considerations, ease of home use, ability to irradiate a large area of tissue at once, possibility of wearable devices, and much lower cost per mW. LED photobiomodulation is here to stay.

Does laser phototherapy influence the proliferation of myoepithelial cells in the salivary gland of hypothyroid rats?

Thyroid hormones influence both development and growth of organs and tissues and guarantee metabolic demands that interfere with the quality of digestive secretions, including those of the salivary glands. Laser phototherapy - LPT can modulate various biological phenomena and its diverse effects permit the action on different cell types. The aim of this study was to evaluate the influence of laser phototherapy on myoepithelial cells of salivary glands of hypothyroid rats. Forty-two albino Wistar rats were divided into two main groups: euthyroid (EU) and hypothyroid (HYPO). Hypothyroidism was induced using propylthiouracil (PTU) for 4weeks. Each group was divided into subgroups: control (without laser) and laser groups (Red/infrared - IR). LPT was used on the submandibular gland and was carried out using a diode laser (λ660 or λ780nm, 40mW, spot size 0.04cm², irradiation area 1cm², 300s, 6J/cm² per gland, 12J/cm² per session) and started two weeks after PTU treatment. LPT was repeated every other day for two weeks. After animal death, the glands were removed, dissected and processed for immunohistochemical analysis. It was observed an increase in the number of myoepithelial cells of hypothyroid control rats in comparison to euthyroid controls (p=0.001). Visible LPT (λ660nm) caused significant higher proliferation of myoepithelial cells in EU rats when compared to IR LPT (λ 780nm)(p≤0.001).It is concluded that, despite the LPT protocol used did not influence myoepithelial proliferation on hypothyroid rats it significantly increased the proliferation on euthyroid animals.

5th Congress of WUWHS Abstract book Florence, Italy September 25–29 2016

The abstract book contains the abstracts of keynote lectures, focus sessions, symposia, workshops, AIUC annual meeting, AISLEC annual meeting, EPUAP annual meeting, ETRS special session, sponsor symposia, oral presentations, poster presentations and the subject index.

The dark art of light measurement: accurate radiometry for low-level light therapy

Lasers and light-emitting diodes are used for a range of biomedical applications with many studies reporting their beneficial effects. However, three main concerns exist regarding much of the low-level light therapy (LLLT) or photobiomodulation literature; (1) incomplete, inaccurate and unverified irradiation parameters, (2) miscalculation of ‘dose,’ and (3) the misuse of appropriate light property terminology. The aim of this systematic review was to assess where, and to what extent, these inadequacies exist and to provide an overview of ‘best practice’ in light measurement methods and importance of correct light measurement. A review of recent relevant literature was performed in PubMed using the terms LLLT and photobiomodulation (March 2014–March 2015) to investigate the contemporary information available in LLLT and photobiomodulation literature in terms of reporting light properties and irradiation parameters. A total of 74 articles formed the basis of this systematic review. Although most articles reported beneficial effects following LLLT, the majority contained no information in terms of how light was measured (73 %) and relied on manufacturer-stated values. For all papers reviewed, missing information for specific light parameters included wavelength (3 %), light source type (8 %), power (41 %), pulse frequency (52 %), beam area (40 %), irradiance (43 %), exposure time (16 %), radiant energy (74 %) and fluence (16 %). Frequent use of incorrect terminology was also observed within the reviewed literature. A poor understanding of photophysics is evident as a significant number of papers neglected to report or misreported important radiometric data. These errors affect repeatability and reliability of studies shared between scientists, manufacturers and clinicians and could degrade efficacy of patient treatments. Researchers need a physicist or appropriately skilled engineer on the team, and manuscript reviewers should reject papers that do not report beam measurement methods and all ten key parameters: wavelength, power, irradiation time, beam area (at the skin or culture surface; this is not necessarily the same size as the aperture), radiant energy, radiant exposure, pulse parameters, number of treatments, interval between treatments and anatomical location. Inclusion of these parameters will improve the information available to compare and contrast study outcomes and improve repeatability, reliability of studies.