Low-level laser therapy is an important tool to treat disorders of the maxillofacial region

Temporomandibular disorders and the use of traditional and laser acupuncture: a systematic review

OBJECTIVE

To evaluate current studies to establish and compare the efficacy of traditional and laser acupuncture in reducing the signs and symptoms of temporomandibular disorders (TMD).

METHODS

PubMed, Cochrane, Scopus, and Web of Science databases were searched. Clinical, controlled, and randomized trials written in English and having used traditional or laser acupuncture as therapy for TMD and RDC/TMD or DC/TMD as a diagnostic criterion for TMD were included.

RESULTS

Six studies that evaluated the intensity of pain and the level of mouth opening of the patients submitted to acupuncture were selected, and all showed improvement. However, similar results were also observed in the groups treated with occlusal splint and placebo acupuncture. Only one study evaluated laser acupuncture and showed a higher proportion of patients with remission of symptoms in the experimental group.

CONCLUSION

The traditional acupuncture seems to relieve the signs and symptoms of TMD, as well as laser acupuncture when associated with occlusal splint. However, more rigorous and high-quality clinical trials are needed.

The outcomes of ultrasonic and laser therapy in case of temporomandibular disorders – an evidence based update

Introduction. Temporomandibular disorders (TMDs) are considered multifactorial conditions, thereby with different therapy options, from occlusal equilibration, splint therapy, pharmacotherapy or physical therapy. Among the physical therapies, over the last years, laser therapy and ultrasound therapy have gained attention, as different experimental or clinical studies suggest their efficacy in case of TMDs. The aim of our literature review is to evaluate the available evidence on the effectiveness of laser and ultrasound therapy in the treatment of temporomandibular disorders. Material and method. A research of literature has been performed - articles published over the last 5 years (January 2016 until June 2021) were searched by introducing a combination of different terms, using the Pubmed, Scopus and Google Scholar databases. Results and discussions. A total number of 332 articles was found. For multiple publications regarding the same group of patients, the most recent studies were included. Initial analysis of titles and abstracts eliminated 232 articles, leaving 35 articles whose full text was examined. 20 articles met the inclusion criteria Conclusions. According to the findings of this literature update we can conclude that low level laser therapy, ultrasound therapy, and photobiomodulation may effectively reduce pain for patients suffering of muscular and joint TMDs. However, their effects appear to be only shortly maintained, and only for less complex cases. In addition, it was difficult to compare the studies included, as they do not offer an optimal usage (program, duration of sessions, or number of sessions) of each technique. In this context, we consider that further randomized clinical studies are necessarily to compare each physical technique as well as their synergic effect on the symptoms in case of temporomandibular disorders. Keywords: temporomandibular disorders, low level laser therapy, ultrasound therapy, photobiomodulation, TMD, LLLT

Photobiomodulation on trigeminal neuralgia: systematic review

Trigeminal neuralgia is a recurrent episode of facial pain, that may be associated with other conditions such as multiple sclerosis, neoplasms, and nerve compromises or may occur due to an unknown cause. The available treatments are pharmacotherapy or surgery; however, both are susceptible to develop side effects. Photobiomodulation could be a promising alternative therapy for trigeminal neuralgia. A systematic review of literature was carried out using the PRISMA protocol, in the PubMed/MEDLINE, Embase, and Web of Science databases. Risk of bias by ROB 2.0 protocol was performed in included studies. Initially, 20 identified articles were collected varying between the years of 1983-2018, from which 6 were included. A total of 193 patients were evaluated; photobiomodulation was compared to conventional therapies, TENS, and therapy combinations with pharmacotherapy. The overall risk of bias was low, with some concerns in the randomization and double-blinding process; moreover, there are few reports in the literature. Photobiomodulation appears to be as effective as conventional therapies, being a coadjutant therapeutic opportunity for the treatment of trigeminal neuralgia.

Efficacy of the LED Red Light Therapy in the Treatment of Temporomandibular Disorders: Double Blind Randomized Controlled Trial

Background

Temporomandibular dysfunction syndrome (TMD) is a common disease among dental patients. It occurs as a consequence of malfunction of the tempromandibular and/or surrounding facial muscles. LED red light therapy is not been well established, and it is important to find out the role of this technique in the treatment of temporomandibular disorders.

Aim of the Study

To evaluate the efficacy of the LED red light in the treatment of the tempromandibular dysfunction syndrome.

Material and Methods

Fifty students of the College of Dentistry/University of Baghdad with myofacial pain associated with Tempromandibular Disorder volunteered to participate in this study and be evaluated during both treatment and follow-up periods. They were 40 (80%) females and 10 (20%) males. Patients were divided into 2 groups: Group A treated by TenDlite® Medical Device model 204 with a LED's of wavelength 660 nm (red light) and Group B given placebo (no treatment at all) by just putting the TenDlite device near the tender points without battery and turning ON the device.

Results

The changes in the pain value and number of the tender muscles in both groups were highly significant, only placebo group less but with no significant differences.

Conclusions

This study showed that red LED therapy could be useful in improving patient's symptoms regarding pain, clicking, and number of tender muscles. In addition, this study showed the importance of the psychological part of treatment of those patients. This trial is registered with TCTR20190406002.

Non-invasive different modalities of treatment for temporomandibular disorders: review of literature

Temporomandibular disorders (TMDs) are diseases that affect the temporomandibular joint and supporting structures. The goal of treatment for TMDs is elimination or reduction of pain and return to normal temporomandibular joint function. Initial treatment for TMDs is non-invasive and conservative, not surgical. Oral and maxillofacial surgeons should fully understand and actively care about non-invasive treatments for TMDs. The purpose of this study is to review the validity and outcomes of non-invasive and surgical treatment modalities for TMDs.

Effect of combined application of high- and low-intensity lasers on dentin hypersensitivity: A randomized clinical trial

Background. Diode lasers (DLs) have demonstrated equal or better desensitizing effects than fluoride varnish, 10% potas-sium nitrate (NK) gel and Gluma. The current study evaluated the desensitizing effect of combined application of DLs with two different output powers and compared it with single DL therapy. Methods. Sixty-two hypersensitive teeth were allocated randomly into two groups: the single group was treated with 3-W DL beam once and in the combined group, the teeth were irradiated three times (the first time with 0.2-W and then with 3-W and the second and third times, 48 and 96 hours after the baseline visit, with 0.2-W DL beams). The amount of dentin hyper-sensitivity (DH) was evaluated, immediately before and after each visit, and 1 week and 1 and 3 months after the first visit. Data analysis was performed using chi-squared test, repeated measurement of ANOVA and Mann-Whitney U test. P<0.05 was considered statistically significant. Results. Statistically significant changes were observed in the means of VAS indices between all the measurement intervals and pretreatment measures, in both experimental groups (P<0.001). The difference in VAS reduction among the groups was not significant when the hypersensitive teeth were stimulated by a periodontal probe and a jet of air (P=0.63 and P=0.12). Conclusion. The results of the present study showed that using both high-intensity and combined DL beams gives rise to significant reductions in DH. There was no significant difference between combined and single laser therapies in the treatment of tooth hypersensitivity.

Therapeutic and Analgesic Efficacy of Laser in Conjunction With Pharmaceutical Therapy for Trigeminal Neuralgia

Introduction: Trigeminal neuralgia (TN) is the most common neuralgia in the head and neck region and a common cause of orofacial pain. It is routinely treated with carbamazepine. Laser, acupuncture and radiofrequency are among other treatment modalities for this condition. This study sought to assess the efficacy of laser therapy in conjunction with carbamazepine for treatment of TN. Methods: A total of 30 patients who met the inclusion criteria were divided into 2 groups of cases and controls (n=15) by double blind randomized controlled clinical trial. All patients received 100 mg carbamazepine at baseline and another 100 mg after 2 days for pain control. In the case group, low level laser therapy (LLLT) was also performed in addition to pharmaceutical therapy. Sham laser was used in the control group instead of LLLT. Treatment was continued for 9 sessions (3 days a week). The intensity of pain was measured and compared in the 2 groups using visual analog scale (VAS) in 3 period. The qualitative variables among the groups were compared using the repeated measures analysis of variance (ANOVA). Results: The severity of pain was lower at the end of treatment in the case compared to the control group so this difference was statistically significant (P=0.003). The severity of pain decreased in both groups over time. Significant difference was noted in this regard between the 2 groups either (P=0.003). At the end of treatment pain intensity dropped in the intervention group from 6/8 to 1/2 and control group from 6/6 to 2/7. Conclusion: Laser therapy did add to the value of pharmaceutical therapy for treatment of TN. Both groups experienced significant improvement over time. So it is better to used laser complementary therapy to reduce side effects and the medicine dosage.

The effect of laser and botulinum toxin in the treatment of myofascial pain and mouth opening: A randomized clinical trial

This study conducted a randomized clinical trial in 15 patients, who sought care at the Dental Clinic of the University of Passo Fundo, in order to compare the use of low-level laser and botulinum toxin in the treatment of myofascial pain and whether they alter the mouth opening of patients with temporomandibular disorder. The patients were divided into two groups: the Laser group received low-level GaAlAs laser, 100mW of power at a wavelength of 830nm in continuous light emission; and the Toxin group received 30U of botulinum toxin type A (BTX-A) in the first session, and 15U after fifteen days. The assessments were performed by measuring pain with Visual Analogue Scale (VAS), and mouth opening with a digital caliper. Data were submitted to Student's t test at 5% significance level. Regarding pain symptoms, the results indicate that groups treated with laser and toxin registered 7U in VAS, at day 5 the scores were 4.75 and 4.86U, respectively. The laser worked faster (day 12) at 2.75U, and the group treated with BTX-A registered 2.86U at day 30. Both therapies investigated were effective in reducing pain, but the effect of low-level laser was faster than the use of BTX-A. Both treatments showed no statistically significant improvement in mouth opening.

Evaluation of Low-Level Laser Therapy in TMD Patients

Light amplification by stimulated emission of radiation (laser) is one of the most recent treatment modalities in dentistry. Low-level laser therapy (LLLT) is suggested to have biostimulating and analgesic effects through direct irradiation without causing thermal response. There are few studies that have investigated the efficacy of laser therapy in temporomandibular disorders (TMD), especially in reduced mouth opening. The case report here evaluates performance of LLLT with a diode laser for temporomandibular clicking and postoperative findings were evaluated in two cases of TMD patients. First patient had a history of limited mouth opening and pain in temporomandibular joint (TMJ) region since nine months. Second patient's main complaint was his restricted mouth opening, which was progressed in one year. LLLT was performed with a 685 nm red probed diode laser that has an energy density of 6.2 J/cm(2), three times a week for one month, and application time was 30 seconds (685 nm, 25 mW, 30 s, 0.02 Hz, and 6.2 J/cm(2)) (BTL-2000, Portative Laser Therapy Device). The treatment protocol was decided according to the literature. One year later patients were evaluated and there were no changes. This application suggested that LLLT is an appropriate treatment for TMD related pain and limited mouth opening and should be considered as an alternative to other methods.

Early results of low-level laser application for masticatory muscle pain: a double-blind randomized clinical study

BACKGROUND

To evaluate the effect of Low Level Laser (LLL) application at the points of greatest pain in patients with chronic masticatory muscle pain.

METHODS

A total number of 30 (21 women, 9 men, with a mean age of 39.2) were selected after the diagnosis of MPDS according to the Research Diagnostic Criteria for Temporomandibular Disorder (RDC/TMD). The patients were randomly divided into three groups; laser group I (n = 10); patients received the LLL at the point of greatest pain, laser group II (n = 10); patients received LLL at pre-established points in the effected muscles and placebo group (n = 10). LLL and placebo were applied three times per week, for a total of 12 sessions. Mandibular mobility was examined, masticator muscles tenderness were assessed and PPT values were obtained. Subjective pain levels were evaluated using VAS. The measurements performed before the treatment and after the completion of the therapy. Descriptive statistics (mean, standard deviation, and frequency) Student's t-test, Mann-Whitney U-test and paired-sample t-tests were used for analysis.

RESULTS

In both laser groups, there was a statically significant reduction in PPT values of the muscles, number of muscles without any pain on palpation increased significantly, mandibular movements' ranges were improved. Laser group I demonstrated statistically better results than the Laser group II in all of the measured values. Plasebo group did not show any statistically difference in any of the measured values.

CONCLUSIONS

LLLT can be accepted as an alternative treatment modality in the management of masticatory muscle pain and direct irradiation seems to effect better.

TRIAL REGISTRATION

Current Controlled Trials ISRCTN31085 , Date of registration 28/08/20145.

The adjunct therapeutic effect of lasers with medication in the management of orofacial pain: double blind randomized controlled trial

OBJECTIVE

This study aimed to evaluate the efficacy of laser therapy in conjunction with a pharmaceutical approach to alleviate myofascial pain dysfunction syndrome.

BACKGROUND DATA

A few clinical studies have evaluated the analgesic effect of laser therapy on orofacial pain, most of which reported controversial results. Myofascial pain dysfunction syndrome (MPDS), trigeminal neuralgia, and atypical facial pain are the most common facial pain.

METHODS

A double-blind randomized controlled trial was designed to evaluate the therapeutic effect of GaAs laser (peak power 10 W; pulse frequency 3000 Hz; average power 0.012 W; wavelength 980 nm; irradiation duration 300 sec; and dose 12.73 J/cm(2)) on the management of common orofacial pain. The laser group (n=30) received 10 sessions of treatment with GaAs laser. The control group (n=30) was treated identically with sham laser. All patients received the appropriate pharmaceutical treatment as well. Visual analog scale (VAS) was recorded for all patients at baseline, and immediately, 2, and 4 months after the final treatment session. The qualitative variables among the groups were compared using the χ(2) test.

RESULTS

Both groups demonstrated a significant reduction in pain with the progression of time (p<0.05). The difference between the two groups was not significant (p>0.05). Whereas laser therapy in the present study failed to show any significance over the control group, the role of covariates such as radiation parameters (wave length, dose) should not be overlooked.

CONCLUSIONS

We found no significant level of efficacy for the GaAs laser in the management of common orofacial pain. Further studies are suggested to evaluate the efficacy of other types of lasers with different parameters in the management of orofacial pains.

The Effect of Low-level Laser Therapy on Trigeminal Neuralgia: A Review of Literature

The effect of low intensity laser radiation in the treatment of acute and chronic pain is now established in many studies. Tri-geminal neuralgia is a pain passes through nerve's branches and its trigger is located in skin or mucosa that could lead to pain with a trigger stimulus. The pain involved branches of trigeminal nerve that sometimes has patients to seek the treatment for several years. Nowadays different treatments are used for relief of pain that most of them cause tolerance and various side effects. This paper reviews and summarizes scientific papers available in English literature publishedin PubMed, Scopus, Science Direct, Inter science, and Iran Medex from 1986 until July 2011 about the effect of these types of lasers on trigeminal neuralgia which is one of the most painful afflictions known. In different studies, the effect of laser therapy has been compared with placebo irradiation or medicinal and surgical treatment modalities. Low-level laser therapy (LLLT) is a treatment strategy which uses a single wavelength light source. Laser radiation and monochromatic light may alter cell and tissue function. However, in most studies laser therapy was associated with significant reduction in the intensity and frequency of pain compared with other treatment strategies, a few studies revealed that between laser and placebo group there was not any significant difference according to the analgesic effect. Low-level laser therapy could be considered in treatment of trigeminal neuralgia without any side effects.

Recurrent aphthous stomatitis and pain management with low-level laser therapy: a randomized controlled trial

OBJECTIVE

The aim of the study was to determine whether low-level laser therapy (LLLT) has an analgesic effect in patients with recurrent aphthous stomatitis (RAS).

STUDY DESIGN

A randomized single-blinded placebo-controlled trial was conducted with LLLT (wavelength, 809 nm; power, 60 mW; pulse frequency, 1800 Hz; duration, 80 seconds per treatment; dose, 6.3 J/cm(2)) in 40 patients with RAS. The intervention group was treated with LLLT on 3 occasions, with a 1-day interval. The control group was treated similarly, without any laser power. Pain perception (visual analog scale [VAS] rating) and patients' experience of eating, drinking, and brushing teeth was registered.

RESULTS

VAS rating decreased (day 0 until day 2) from 84.7 to 31.5 (LLLT) and from 81.7 to 76.1 (placebo) (P < .0001). LLLT also relieved the difficulty of drinking, eating, and brushing teeth.

CONCLUSIONS

LLLT reduced the pain and the inconvenience of eating, drinking, and brushing teeth for patients with RAS, compared with placebo.

Evaluation of anti-nociceptive and anti-inflammatory activity of low-level laser therapy on temporomandibular joint inflammation in rodents

The aim of this study was to investigate the analgesic and anti-inflammatory activity of low-level laser therapy (LLLT) on the nociceptive behavioral as well as histomorphological aspects induced by injection of formalin and carrageenan into the rat temporomandibular joint. The 2.5% formalin injection (FRG group) induced behavioral responses characterized by rubbing the orofacial region and flinching the head quickly, which were quantified for 45 min. The pretreatment with systemic administration of diclofenac sodium-DFN group (10 mg/kg i.p.) as well as the irradiation with LLLT infrared (LST group, 780 nm, 70 mW, 30 s, 2.1 J, 52.5 J/cm(2), GaAlAs) significantly reduced the formalin-induced nociceptive responses. The 1% carrageenan injection (CRG group) induced inflammatory responses over the time-course of the study (24 h, and 3 and 7 days) characterized by the presence of intense inflammatory infiltrate rich in neutrophils, scanty areas of liquefactive necrosis and intense interstitial edema, extensive hemorrhagic areas, and enlargement of the joint space on the region. The DFN and LST groups showed an intensity of inflammatory response that was significantly lower than in CRG group over the time-course of the study, especially in the LST group, which showed exuberant granulation tissue with intense vascularization, and deposition of newly formed collagen fibers (3 and 7 days). It was concluded that the LLLT presented an anti-nociceptive and anti-inflammatory response on the inflammation induced in the temporomandibular joint of rodents.

Management of Temporomandibular Disorders with Low Level Laser Therapy

PURPOSE

To evaluate the efficacy of low level laser therapy (LLLT) in the treatment of temporomandibular disorders (TMD) in relation to pain intensity, tender points, joint sounds and jaw movements.

MATERIALS AND METHODS

Twenty patients received 6 sessions of LLLT (3 times a week for 2 weeks) with semiconductive diode laser (gallium arsenide; 904 nm, 0.6 W, 60 s, 4 J/cm(2)). Pain intensity, number of tender points, joint sounds and active range of motion were assessed before and immediately after each session and after 1, 2 weeks, 1, 3 and 6 months.

RESULTS

Statistically significant results were achieved in all study parameters.

CONCLUSION

LLLT promoted satisfactory results in reducing the pain intensity, number of tender points, joint sounds and improvement in the range of jaw motion. Hence it is an effective and efficient treatment method for TMDs.

Effect of low-level laser therapy on pain levels in patients with temporomandibular disorders: a systematic review

Temporomandibular disorders (TMD) are characterized by the presence of temporomandibular joint (TMJ) and/or masticatory muscle pain and dysfunction. Low-level laser is presented as an adjuvant therapeutic modality for the treatment of TMD, especially when the presence of inflammatory pain is suspected.

Clinical effectiveness of laser acupuncture in the treatment of temporomandibular joint disorder

BACKGROUND/PURPOSE

Temporomandibular joint disorder (TMD) is a general term for diseases of the temporomandibular joint and orofacial muscles. In this study, we tested whether laser acupuncture was effective for the treatment of TMD.

METHODS

Twenty patients with TMD were treated with diode K-Laser (wavelength 800 nm, energy density 100.5 J/cm(2)) once a week at four acupuncture points including three standard ipsilateral local points (ST6, ST7, Ashi point) and one contralateral distal point (LI4). A 10-cm visual analogue scale (0 no pain and 10 the most severe pain) was used for measuring the pain intensity before and after the treatment.

RESULTS

Seventeen out of 20 patients (85%) showed various degrees of pain relief after laser acupuncture treatment. The average pain score was 6.3 ± 1.6 before treatment and 2.5 ± 2.2 after treatment. Significant pain relief after laser acupuncture treatment was achieved (p = 0.0003, Wilcoxon signed rank test). The 17 patients showed an average pain relief of 63 ± 31%. There were six patients who showed no TMD symptoms after an average of four treatments of laser acupuncture. The other 11 patients showed partial relief of TMD symptoms after treatment. Although the pain was still present, it was less and was acceptable. No side effects were reported in any patients during or after laser acupuncture treatments.

CONCLUSION

Laser acupuncture may be an alternative treatment modality for TMD because it is non-invasive, results in partial or total relief of pain, and has no side effects.

Effect of low level laser on sutured wound healing in rats

PURPOSE

To evaluate the effect of low-level laser therapy (LLLT) ë904 nm on healing of surgical wounds in rats.

METHODS

Forty male Wistar rats were used, divided into four groups, underwent incision along the lines Alba covering skin, subcutaneous and muscle abdominal, sutured continuously for nylon 5-0. Eight and fifteen days after the surgery process, the repairing area was removed and histological sections were stained with hematoxylin-eosin to assess cellularity inflammatory, Masson's Trichrome and Picrossirus to quantify the collagen fibers and immunohistochemical technique for counting newly formed vessels. The data were compared statistically using analysis of variance ANOVA, with a "post-hoc Tukey test, p <0.05.

RESULTS

Low-level laser therapy reduced the intensity of the inflammatory reaction and influenced the dynamic of the immunoinflammatory response by inducing switching of the leukocyte infiltration pattern (neutrophilic to lymphoplasmacytic infiltration). Also stimulate the deposition and enhance the organization of collagen fibers, featuring a delicate collagen type III. Furthermore, it appeared to a significant increase in the average number of newly formed vessels (p = 0.00 and p = 0.02, respectively).

CONCLUSION

Low-level laser therapy resulted in modulate of the inflammatory response, enhanced deposition of collagen fibers and increase in the average number of newly formed vessels.

Management of myofascial pain: low-level laser therapy versus occlusal splints

The present study was designed to compare the effects of low-level laser with occlusal splints in patients with signs and symptoms of myofascial pain (MP) dysfunction syndrome. A total of 40 (34 women and 6 men, with a mean age of 32.84 [SD, 10.70] years) were selected after the diagnosis of MP according to the Research Diagnostic Criteria for Temporomandibular Disorder. The patients were randomly divided into 2 groups: study group (n = 20) and control group (n = 20). Low-level laser was applied to patients in the study group 2 times per week, for a total of 10 sessions. Patients in the control group were instructed to wear occlusal splints 24 h/d for 3 months. The functional examination was based on Research Diagnostic Criteria for Temporomandibular Disorder and pressure pain threshold values were obtained with the aid of an algometer in both groups. Patients' self-report of pain was evaluated with visual analog scale. Comparisons were made within and between the groups before and after treatment. Vertical movements showed statistically significant improvements after the treatments in both groups (P < 0.01), but when the groups were compared with each other, there were no significant difference between the groups. In both groups, tenderness to palpation of the muscles decreased significantly. Pressure pain threshold evaluations and visual analog scale scores revealed similar results, too. This particular type of low-level laser therapy (820 nm, 3 J/cm2, 300-mW output power) is as effective as occlusal splint in pain release and mandibular movement improvement in MP.

Assessment of the effect of the use of laser light or dantrolene on facial muscle under occlusal wear: a Raman spectroscopic study in a rodent model

OBJECTIVE

The aim of the present study was to use Raman spectroscopy to measure levels of CaPi in muscles under occlusal wear and treated with laser phototherapy (LPT) or muscle-relaxant therapy or both on rodents.

BACKGROUND

The etiology of temporomandibular disorders is multifactorial. Malocclusion may influence the masticatory muscles, causing fatigue. A major type of fatigue is the metabolic, caused by the increased accumulation of metabolites such as inorganic phosphate. Raman spectroscopy allows nondestructive analysis of the biochemical composition of tissues.

METHODS

The 30 male Wistar rats were randomly divided into three groups: occlusal wear (G-1), occlusal wear + LPT (G-2), and occlusal wear + muscle relaxant (G-3). Ten untreated animals were used for baseline data. Under intraperitoneal general anesthesia, animals of groups 1, 2, and 3 had unilateral amputation of molar cusps to simulate an occlusal-wear situation. The masseter muscle of G-2 received LPT (lambda830 nm, 4 J/cm(2), 40 mW, phi approximately 2 mm) after the procedure and repeated every other day for 14-30 days. Animals of G-3 were treated with a daily injection of dantrolene (2.5 mg/kg in 0.5 ml of H(2)O) beginning 24 h after cusp removal. Animals were killed with an overdose of general anesthetics at days 14 and 30 after cusps removal, and the ipsilateral masseter muscle was excised and divided into two parts. One part was routinely processed and underwent histologic analysis; the other was kept in liquid nitrogen for Raman spectroscopy. The mean value of the intensity of the peak 958 per centimeter was determined.

RESULTS

No morphologic changes were seen. Raman analysis showed significantly less Raman intensity in the laser group at 30 days (p < 0.01).

CONCLUSION

Occlusal wear did not caused morphologic alterations in the masseter muscle but resulted in changes of the levels of CaP(i) that were less compromising when the laser light was used.

Efficacy of low-level laser therapy in the treatment of temporomandibular disorder

AIMS

To evaluate the effectiveness of low-level laser therapy (LLLT) in patients presenting with temporomandibular disorder (TMD) in a random and placebo-controlled research design.

METHODS

The sample consisted of 40 patients, divided into an experimental group (G1) and a placebo group (G2). The treatment was done with an infrared laser (830nm, 500mW, 20s, 4J/point) at the painful points, once a week for four consecutive weeks. The patients were evaluated before and after the treatment through a Visual Analogue Scale (VAS) and the Craniomandibular Index (CMI).

RESULTS

The baseline and posttherapy values of VAS and CMI were compared by the paired T-test, separately for the placebo and laser groups. A significant difference was observed between initial and final values (p < 0.05) in both groups. Baseline and post-therapy values of pain and CMI were compared in the therapy groups by the two-sample T-test, yet no significant differences were observed regarding VAS and CMI (p > 0.05).

CONCLUSION

After either placebo or laser therapy, pain and temporomandibular symptoms were significantly lower, although there was no significant difference between groups. The low-level laser therapy was not effective in the treatment of TMD, when compared to the placebo.

Low intensity laser therapy in the treatment of temporomandibular disorders: a double-blind study

This study aimed to evaluate the effectiveness of low intensity laser therapy (LILT) in 30 patients presenting temporomandibular joint (TMJ) pain and mandibular dysfunction in a random and double-blind research design. The sample, divided into experimental group (1) and placebo group (2), was submitted to the treatment with infrared laser (780 nm, 30 mW, 10 s, 6.3 J/cm(2)) at three TMJ points. The treatment was evaluated throughout six sessions and 15, 30 and 60 days after the end of the therapy, through visual analogue scale (VAS), range of mandibular movements and TMJ pressure pain threshold. The results showed a reduction in VAS (p < 0.001) and through the ANOVA with repeated measures it was observed that the groups did not present statistically significant differences (P = 0.2060), as the averages of the evaluation times (P = 0.3955) and the interaction groups evaluation times (P = 0.3024), considering the MVO. The same occurred for RLE (P = 0.2988, P = 0.1762 and P = 0.7970), LLE (P = 0.3265, P = 0.4143 and P = 0.0696), PPTD (P = 0.1558, P = 0.4695 and P = 0.0737) and PPTE (P = 0.2376, P = 0.3203 and P = 0.0624). For PE, there were not statistically significant differences for groups (P = 0.7017) and the interaction groups evaluation times (P = 0.6678), even so in both groups the PE varied with time (P = 0.0069).

Effect of low-level laser therapy on Candida albicans growth in patients with denture stomatitis

OBJECTIVE

The purpose of our report is to present the effect of low-level laser therapy on Candida albicans growth and palatal inflammation in two patients with denture stomatitis.

BACKGROUND DATA

The most common oral mucosal disorder in denture wearers is denture stomatitis, a condition that is usually associated with the presence of the yeast Candida albicans. Different treatment methods have been suggested to treat this symptom, none of which is proven to be absolutely effective.

METHODS

Two denture-wearing patients, both with palatal inflammation diagnosed as Newton type II denture stomatitis were treated with low-power semiconductor diode laser (BTL-2000, Prague, Czech Republic) at different wavelengths (685 and 830 nm) for 5 d consecutively. In both patients, palatal mucosa and acrylic denture base were irradiated in noncontact mode (probe distance of 0.5 cm from irradiated area) with different exposure times-5 min (830 nm, 3.0 J/cm2, 60 mW) and 10 min (685 nm, 3.0 J/cm2, 30 mW). The effect of laser light on fungal growth in vivo was evaluated after the final treatment using the swab method and semiquantitative estimation of Candida albicans colonies growth on agar plates. The severity of inflammation was evaluated using clinical criteria.

RESULTS

After lowlevel laser treatment, the reduction of yeast colonies on the agar plates was observed and palatal inflammation was diminished.

CONCLUSION

LLLT is effective in the treatment of denture stomatitis. Further placebo controlled studies are in progress.

Changes in sensory and pain perception thresholds after linear polarized near-infrared light radiation in the trigeminal region

Linearly polarized light in the near-infrared portion of the spectrum has recently been associated with a variety of musculoskeletal disorders including temporomandibular disorders. The purpose of this study was to determine whether short-term linearly polarized near-infrared light radiation in the trigeminal region affects sensory and pain perception thresholds in the trigeminally mediated region and in the cervically mediated region of normal subjects. Thirty-five normal female volunteers participated in this study. Each subject received an 8-minute course of irradiation in the right cheek, and sensory/nociceptive perception thresholds were compared before and immediately after the irradiation in the right cheek and the right forearm. As a result, this study demonstrated a significant elevation of the heat-induced pain threshold in both regions and a tendency for the warm sensation threshold to elevate in the cervical region. In addition, a significant increase in vibratory sensitivity was observed in the trigeminal region. In conclusion, our results provided additional evidence that the warming sensation has a negative feedback influence on heat pain intensity in humans, and provides a theoretical basis for the application of linear polarized near-infrared light radiation to the trigeminal region.

Physiotherapy in the management of TMD: A review of the literature part 2

The second section of this two-part article assessing the effectiveness of physiotherapy in the treatment of temporomandibular disorders (TMD) examines the effectiveness of electrotherapy modalities, mobilizations and manipulation techniques. This article concludes that from the studies reviewed, there appears to be insufficient current literature to determine whether different electrotherapy modalities or mobilization techniques are effective in treating TMD.

Although the literature largely supports the application of temporomandibular manipulation to treat disc displacement TMD, many methodological limitations were identified within the evidence base, making it inappropriate to state how effective manipulation is in treating such patients. There remains insufficient evidence to assess the effectiveness of this treatment on muscle disorder or diagnoses TMD.

Based on critical appraisal, it was recommended that the evidence base requires a number of large, well designed, blinded randomized control trials with between-group comparisons, to determine how effective these three physiotherapy modalities are in the treatment of TMD.

The influence of low-level laser therapy on biomodulation of collagen and elastic fibers

The study of low-level laser therapy upon extracellular matrix elements is important to understand the wound healing process under this agent. However, little is known about the interference of laser light in relation to collagen and elastic fibers. Cutaneous wounds were performed on the back of 72 Wistar rats and a Ga-Al-As low-level laser was punctually applied with different energy densities. The animals were killed after 24, 48, 72 hours and 5, 7 and 14 days. Tissues were stained with hematoxilin-eosin, sirius red fast green and orcein and then analyzed. It was observed that the treated group exhibited larger reduction of edema and inflammatory infiltrate. The treated animals presented a larger expression of collagen and elastic fibers, although without statistical significance (p > 0.05). Treatment with a dosage of 4 J/cm² exhibited more expressive results than that with 8 J/cm². In this study, the authors concluded that low-level laser therapy contributed to a larger expression of collagen and elastic fibers during the early phases of the wound healing process.

Effects of low-power laser exposure on masseter muscle pain and microcirculation

One possible cause of the reported positive treatment effect by low-power laser exposure in muscle pain conditions could be that it increases the local microcirculation. The aim of this study was therefore to investigate the immediate effects on masseter muscle blood flow by low-power laser exposure in patients with chronic orofacial pain of muscular origin in comparison to healthy individuals. Twelve patients with myofascial pain of orofacial muscles and 12 age and gender matched healthy individuals participated in the study. Before laser exposure the subjects were examined clinically and the patients scored their current pain intensity from the most tender masseter muscle. Intramuscular laser-Doppler flowmetry was performed unilaterally in the most tender point (patients) or in a standardized point (healthy subjects) of the masseter muscle. The muscle was first exposed with a Gallium-Aluminum-Arsenide laser (active laser) or placebo laser for 2 min in a randomized and double-blind manner. After another 8 min the muscle was treated with the other laser for 2 min and the LDF recording continued for 8 min. Finally, the patients again assessed the pain intensity. Data were analyzed blindly by one of the authors not participating in data collection. The pain intensity was not affected by laser exposure. The blood flow did not change significantly in the patients, but increased after active laser exposure and decreased after placebo exposure in the healthy individuals. The difference between active laser and placebo was significant. In conclusion, the results of this study do not support an effect of low-power laser exposure on masseter muscle microcirculation in patients with chronic orofacial pain of muscular origin.

Influence of low level laser therapy on wound healing and its biological action upon myofibroblasts

BACKGROUND AND OBJECTIVE

In re-evaluating the effects of laser therapy in wound healing, the role of extracellular matrix elements and myofibroblasts, was analyzed.

STUDY DESIGN/MATERIALS AND METHODS

Cutaneous wounds were inflicted on the back of 72 Wistar rats. Low level laser was locally applied with different energy densities. Lesions were analyzed after 24, 48, 72 hours and 5, 7, and 14 days. Tissues were studied by histology, immunohistochemistry, and electron microscopy.

RESULTS

In treated animals, the extent of edema and the number of inflammatory cells were reduced (P < 0.05), but the amount of collagen and elastic fibers appeared slightly increased. Desmin/smooth muscle alpha-actin-phenotype myofibroblasts were statistically more prominent on the 3rd day after surgery (P < 0.05) in treated wounds than in controls. Treatment with a dosage of 4 J/cm(2) was superior to that with 8 J/cm(2).

CONCLUSIONS

Laser therapy reduced the inflammatory reaction, induced increased collagen deposition and a greater proliferation of myofibroblasts in experimental cutaneous wounds.

Low-level laser irradiation attenuates production of reactive oxygen species by human neutrophils

OBJECTIVE

The aim of this study was to examine the effects of low-level laser therapy (LLLT) on production of reactive oxygen (ROS) species by human neutrophils.

BACKGROUND DATA

LLLT is an effective therapeutic modality for inflammatory conditions.

MATERIALS AND METHODS

The laser device used was the infrared diode laser (GaAlAs), 830-nm continuous wave (150 mW/cm(2)). After irradiation, ROS production by neutrophils was measured using luminol-dependent chemiluminescence (LmCL) and expression of CD11b and CD16 on neutrophil surface was measured by flow cytometry.

RESULTS

The LmCL response of neutrophils was reduced by laser irradiation at 60 min prior to the stimulation with opsonized zymosan and calcium ionophore. The attenuating effect of LLLT was larger in neutrophils of smokers than non-smokers, while the amount of produced ROS was larger in neutrophils of smokers. Expression of CD11b and CD16 on neutrophil surface was not affected by LLLT.

CONCLUSION

Attenuation of ROS production by neutrophils may play a role in the effects of LLLT in the treatment of inflammatory tissues. There is a possible usage of LLLT to improve wound healing in smokers.