Laser therapy on points of acupuncture: Are there benefits in dentistry?

Effectiveness of Laser Acupuncture for Reducing Pain and Increasing Mouth Opening Range in Individuals with Temporomandibular Disorder: A Systematic Review and Network Meta-Analysis

PURPOSE OF REVIEW

Laser acupuncture (LA) demonstrates promising results in the treatment of musculoskeletal disorders. However, its effects on temporomandibular disorder (TMD) are not yet fully understood. Thus, the aim of this systematic review and network meta-analysis was to assess the effectiveness of LA on pain intensity and maximum mouth opening range (MMO) related to TMD. A search was carried out in 11 electronic databases and references of included studies to locate randomized clinical trials (RCTs) that evaluated LA as a primary treatment for TMD. The risk of bias was assessed using the RoB 2 tool. Network meta-analysis was conducted on the MetaInsight platform, considering the pain intensity and counseling (C) as the outcome of reference. The GRADE system was used to assess the certainty of the evidence.

RECENT FINDINGS

Five studies evaluated pain intensity, four with a high risk of bias and one with a low risk. Two studies evaluated pain intensity on palpation (one with high and one with low risk of bias), and one study with high risk of bias evaluated MMO. Laser parameters were: 690-810 nm, 40-150 mW, and 7.5-112.5 J/cm2. Occlusal splint (OS) [- 2.47; CI 95% - 3.64, - 1.30] and Physiotherapy (PT) [-2.64; CI 95% - 3.94, - 1.34] reduced pain intensity compared to C. The ranking of treatments in order of effectiveness was PT > OS > LA > C > CR (craniopuncture). The certainty of the evidence was very low or low. The data do not support the indication of LA for the treatment of TMDs and new placebo-controlled RCTs must be conducted to demonstrate its effectiveness more precisely.

Laser acupuncture to reduce temporomandibular disorder (TMD) symptoms: systematic review and meta-analysis

The application of low-level laser therapy (LLLT) to acupuncture points may produce effects similar to that of needle stimulation in patients with temporomandibular disorders (TMD). This systematic review was conducted according to the Cochrane Collaboration guidelines and aimed to address clinical questions using the following strategy: Patient/Problem, Intervention, Comparison, and Outcome (PICO). A comprehensive literature search was performed upto April 26, 2023, across nine electronic databases (BVS, PubMed, Scopus, Embase, Web of Science, ScienceDirect, Cochrane Library, Latin American and Caribbean Health Sciences Literature (LILACS), and Google Scholar) supplemented with gray literature. The risk of bias in randomized and nonrandomized clinical trials was assessed using two tools: risk-of-bias (RoB) 2 and Risk Of Bias In Non-randomised Studies-of Interventions (ROBINS-I). Meta-analysis involved the extraction of mean and standard deviation values for spontaneous pain and mouth opening levels. Seven studies were included in this review, all of which used LLLT. The applied wavelengths ranged from 690 to 810 nm without significant variations in light emission patterns. LLLT demonstrated a significant reduction in instantaneous pain levels (standard mean difference [SMD] = 3.85; 95% confidence interval [CI] = 2.09, 5.62; p < 0.003) and an improvement in instantaneous mouth opening ability (mean difference [SMD] = -7.15; 95% CI = -11.73, -2.58; p < 0.002), with low certainty of evidence. LLLT may alleviate symptoms in patients with TMD; however, caution should be exercised when interpreting the results because of protocol variations among studies and the limited number of studies included in the meta-analysis.

What are the best parameters of low-level laser therapy to reduce pain intensity and improve mandibular function in orofacial pain? A systematic review and meta-analysis

PURPOSE

To determine the effectiveness of laser therapy for managing patients with orofacial pain (OFP). In addition, to determine which parameters provide the best treatment effects to reduce pain, improve function, and quality of life in adults with OFP.

METHODS

Systematic review. Searches were conducted in six databases; no date or language restrictions were applied. Studies involving adults with OFP treated with laser therapy were included. The risk of bias (RoB) was performed with the Revised Cochrane RoB-2. A meta-analysis was structured around the OFP type, and outcomes. Grading of Recommendations, Assessment, Development, and Evaluation (GRADE) assessed the overall certainty of the evidence.

RESULTS

Eighty-nine studies were included. Most studies (n = 72, 80.9%) were considered to have a high RoB. The results showed that laser therapy was better than placebo in improving pain, maximal mouth open (MMO), protrusion, and tenderness at the final assessment, but with a low or moderate level of evidence. The best lasers and parameters to reduce pain are diode or gallium-aluminum-arsenide (GaAlAs) lasers, a wavelength of 400-800 or 800-1500 nm, and dosage of <25 J/cm2.

CONCLUSIONS

Laser therapy was better than placebo to improve pain, MMO, protrusion, and tenderness. Also, it was better than occlusal splint to improve pain, but not better than TENS and medication.Implications for rehabilitationLaser therapy was found to be good in improving pain, maximal mouth opening, jaw protrusion, and tenderness at the end of the treatment.For patients with all types of temporomandibular disorders (TMDs) (myogenous, arthrogenous, and mixed), the following lasers and parameters are recommended: diode or gallium-aluminum-arsenide (GaAlAs) laser, wavelength of 400-800 or 800-1500 nm, and a dosage <25 J/cm2.For patients with arthrogenous TMDs, the following lasers and parameters are recommended: Diode laser and a wavelength between 400 and 800 nm.For patients with myogenous TMDs, the following lasers and parameters are recommended: diode laser, wavelength between 800 and 1500 nm, and dosage of <25 J/cm2.For patients with mixed TMDs, the following lasers and parameters are recommended: diode, GaAlAs, or infrared laser, a wavelength of 800-1500 nm, a dosage >100 J/cm2, and an application time between 15 and 30 s or >60 seconds.

Laser acupuncture in the treatment of neuropathies in dentistry: a systematic review

Laser acupuncture can be used to treat neurosensory alterations and motor disorders caused by dental treatments. This study aimed to review the existing literature on the effects of laser acupuncture on neuropathies in the context of dentistry and to search for treatment modalities in which this technique is used. This systematic review was conducted in accordance with the Cochrane Collaboration guidelines and the PICOS strategy. Randomized clinical trials that evaluated laser acupuncture as a primary intervention for facial neuropathy were included. We searched the database for relevant studies and manually searched the gray literature until April 2022, and finally included four studies. The study was considered eligible if it included patients with paresthesia, facial paralysis, or neuralgia, neuropathies within dentistry, and referred to the application of laser acupuncture as a treatment method. The risk of bias was assessed using the RoB 2 tool. It was observed that the recommended wavelengths ranged from 790 nm to 810 nm, with a frequency of at least two applications per week, and to a greater or lesser degree, all evaluated studies obtained an improvement in sensory or motor recovery of the facial nerves. The use of laser acupuncture presented itself as a viable alternative in dentistry for the treatment of paresthesia and facial paralysis due to its therapeutic potential in neuropathic treatment (CRD42022344339).

Effect of low-level laser stimulation of acupuncture points in pediatric dentistry: a systematic review

The biomodulatory potential of low-level laser therapy (LLLT) has prompted investigations of different outcomes in health. One line of research is the stimulation of acupuncture points for the relief of different signs and symptoms related to the stomatognathic system. In dentistry, some studies in pediatric dentistry have demonstrated the benefit of LLLT therapies in the management of dental anxiety in children. This systematic review aimed to analyze previous clinical studies on the application of LLLT at acupoints among pediatric dental patients. This systematic review was conducted according to the Cochrane Collaboration guidelines and the population, intervention, comparison, and outcome strategy. A broad literature search up to June 17, 2022, was performed using four electronic databases (PubMed, Scopus, Embase, and Google Scholar). The risk of bias in randomized clinical trials was assessed using the RoB 2 tool. A total of four studies using LLLT for photobiomodulation were included (n = 4). The most common wavelengths used were in the infrared range (variation between 716 nm and 980 nm). There were little variations in the application time (14 s to 1 min) and exposure dose (1 to 5 joules). LLLT acted positively on different acupuncture points. LLLT provided various benefits and optimized dental practice by reducing the gag reflex during radiography and impression taking, preanesthetic pain, and symptoms of sleep bruxism in the pediatric dental population. Only one of the evaluated studies had a high risk of bias. The LLLT at acupuncture points is associated with positive results on sleep bruxism, preanesthetic pain, and gag reflex in pediatric dentistry. Future research studies should prioritize standardization of the study design and the methods of analysis.

Comparative analysis of two laser wavelengths in the stimulation of acupuncture points for analgesic effects in an animal model

This study compares the effectiveness of two laser wavelengths for stimulating acupoints in an experimental model of acute postoperative pain. Forty-five Wistar rats were randomly assigned to receive treatment on their left hind paw, contralateral to a surgical procedure. Laser treatments were performed with Green Laser-GL (532 nm, 70 mW and 7 J/cm² of energy), Red Laser-RL (660 nm, 100 mW and 7 J/cm² of energy), or with Laser Off-LO. After each application, the animals were evaluated with a Von Frey analgesiometer to check for painful sensitivity on their right (with surgery) and left (without surgery) hind paws. Neuropeptides and cytokine levels in the incision site tissue of the right paw were measured by ELISA after 1, 6 and 24 hours. It was possible to observe that, in this pain model, both lasers promoted analgesia and that the GL altered the levels of TNF-α and IL-1β.

The efficacy of low-level diode laser versus laser acupuncture for the treatment of myofascial pain dysfunction syndrome (MPDS)

Background

Methods

Results

Conclusion

Effect of Low-level Laser on LI4 Acupoint in Pain Reduction during Local Anesthesia in Children

Background

Pain is a multidimensional construct that involves sensory, emotional, and cognitive processes. It is an essential component of child behavior guidance. The injection of a local anesthetic agent during pediatric dental treatment is one of the most painful and distressing procedures performed, stimulation of acupoint LI4 provides an analgesic effect in the orofacial region, thus decreasing the pain during injection.

Aims and objectives

To compare and evaluate the effect of low-level laser on LI4 acupoint and surface-acting 20% benzocaine gel during local anesthesia.

Materials and methods

Children of age-group between 5 years and 9 years receiving bilateral local anesthesia were scheduled for dental treatment. Split-mouth cross-over study was planned and was divided into two groups, receiving low-level laser acupuncture on LI4 acupoint with placebo as a moist cotton swab in the first visit and 20% benzocaine gel with placebo as low-level laser acupuncture off mode in second visit and vice versa. Pain intensity was evaluated using the sound eye motor scale as subjective scale, Wong–Bakers pain rating scale. Pulse rate was measured before, during, and after the procedure using a pulse oximeter.

Results

The average heart rate, Wong–Bakers pain rating scale, and Sound Eye Motor scale were significantly lower in the group having low-level laser when compared with the group having placebo low-level laser therapy.

Conclusion

The low-level laser can be used to control pain during local anesthesia in children.

How to cite this article

Sandhyarani B, Pawar RR, Patil AT, et al. Effect of Low-level Laser on LI4 Acupoint in Pain Reduction during Local Anesthesia in Children. Int J Clin Pediatr Dent 2021;14(4):462–466.

Masticatory Myofascial Pain Syndrome: Implications for Endodontists

INTRODUCTION

Masticatory myofascial pain syndrome can present similarly to other dental conditions in odontogenetic structures. Endodontists should be familiar with the symptomology and pathophysiology of masticatory myofascial pain syndrome to avoid misdiagnosis, incorrect treatment, and medicolegal repercussions. The aim of this review was to provide a foundational summary for endodontists to identify and correctly manage masticatory myofascial pain syndrome.

METHODS

A narrative review of the literature was performed through a MEDLINE search and a hand search of the major myofascial pain textbooks.

RESULTS

Masticatory myofascial pain syndrome is a musculoligamentous syndrome that can present similarly to odontogenic pain or refer pain to the eyebrows, ears, temporomandibular joints, maxillary sinus, tongue, and hard palate. Currently, the most comprehensive pathophysiology theory describing masticatory myofascial pain syndrome is the expanded integrated hypothesis. The most widely accepted diagnostic guidelines for masticatory myofascial pain syndrome are the Diagnostic Criteria for Temporomandibular Disorders; however, their diagnostic capability is limited. There is no hierarchy of treatment methods because each patient requires a tailored and multidisciplinary management aimed at regaining the muscle's range of motion, deactivating the myofascial trigger points, and maintaining pain relief.

CONCLUSIONS

The pain patterns for masticatory myofascial pain syndrome are well-known; however, there is a lack of consensus on the most proper method of trigger point diagnosis or pain quantification. The diagnostic strategies for masticatory myofascial pain syndrome vary, and the diagnostic aids are not well developed.

Influence of Electroacupuncture and Laser-Acupuncture on Treating Paresthesia in Patients Submitted to Combined Orthognathic Surgery and Genioplasty

Objective: The goal of this research was to observe the influence of electroacupuncture (EA) and laser-acupuncture on the return of tactile/pain sensitivity in patients who underwent orthognathic surgery. Materials and Methods: Thirty volunteers subjected to orthognathic surgery were evaluated and randomly divided into 2 groups, in which 3 treatments were evaluated: control (n = 30) (G0, medication + placebo laser treatment) and 2 experimental treatments (n = 15) (G1, medication + EA) or G2 (medication + laser-acupuncture). The control group had n = 30 because for each experimental treatment conducted on a volunteer's hemi-face, there was a control treatment on the other hemi-face. In G1, medication was given with EA, with needles placed at predetermined points (ST 4 [Dicang], M-HN-18 [Jiachengjiang], CV 24 [Chengjiang], ST 5 [Daying], ST 6 [Jiache], and point A1 [YNSA]). For electrostimulation, the device used delivered transcutaneous electrical nerve stimulation of a burst type, with intensity and frequency variations of T = 220 ms and F = 4 Hz (30 minutes, 2 × /week). In G2, in addition to the medication, laser irradiation (at 780 nm) was applied on acupuncture points (at 0.04 cm², 70 mW, 6 s/point, 0.42 J/point, 10 J/cm², 2 × /week). All volunteers were evaluated before and during the 4 months following the surgery. Tactile sensitivity was assessed by mechanical brushing (brush #s 2 and 12) and by a 2-point discrimination test, using a bow compass. A pain test was performed with a pulp electrical test that stimulates intact nerves of the dentin-pulp complex. A Kaplan-Meier test was performed, and survival curves were plotted for comparison between groups. Cox regression analysis was also conducted (α = 0.05). Results: There were no statistically significant differences among the groups for the 2-point discrimination test (brushes #2 and #12) on the buccal mucosa region and for the pulp test on all evaluated regions. However, the tactile test using brush #12 revealed significant differences between G1 and the other groups when considering the lower lip (P = 0.024) and chin (P = 0.028) areas. Conclusions: Only EA was able to influence-using the brushing test (brush #12)-the return of tactile sensitivity on the chin and lower lip positively after combined orthognathic surgery and genioplasty.