Background: Temporomandibular disorder (TMD) is a condition encompassing clinical symptoms of the temporomandibular joint, chewing muscle, and surrounding structures. Laserneedle acupuncture (LNA), a nonthermal and low-intensity laser irradiation used to stimulate acupoints, has been reported as effective for treating chronic musculoskeletal disorders, including TMD, but a lack of well-designed randomised controlled trials (RCTs) means there is insufficient evidence to prove the efficacy of LNA.
Methods: this study is a two-arm parallel, assessor-blinded, randomised controlled trial. We will enrol 40 chronic TMD patients from the Clinical Gnathology Unit of Sapienza University of Rome according to DC/TMD diagnostic criteria, and randomly allocate 20 patients each to an LNA group and a conventional gnathological therapy group (CT). The LNA treatment will be administered in 8 sessions, twice a week for 4 weeks. The CT group will undergo the conventional gnathological treatment (occlusal device) and will be visited after 4 weeks from the start of therapy. For both groups there will be a follow-up visit 8 weeks from baseline. The primary outcome is the difference in Verbal Numeric Scale (VNS) score for TMD pain between baseline and week 4. Secondary outcomes will be temporomandibular joint range of motion, the Italian version of Beck's Depression Index-II (BDI-II), Jaw Functional Limitation Scale (JFLS), Patient Global Impression of Change (PGIC) scores, and quality of life (validated questionnaire). Using data on adverse events and cost-effectiveness in the two groups, we will perform a safety assessment and a cost-effectiveness analysis.
Purposes: this study will assess the efficacy and safety of LNA compared with CT for improving pain, functional/emotional impairment and quality of life in chronic TMD patients. This RCT will provide evidence for the efficacy, safety, and economics of LNA.
Although laser acupuncture is used for treating pain of various musculoskeletal disorders, including TMD, there is currently a lack of evidence regarding its efficacy for TMD-related pain.
Most of the literature studies addressing the use of acupuncture or LA for TMD pain management are case reports. Thus, well-designed clinical studies and RCTs about these topics are still needed, also due to the growing interest in alternative or complementary treatments in chronic pain management, by both patients and physicians.
The novelty and advantages of this study are as follows.
First, this is the first RCT investigating the effectiveness, safety, and economics of laserneedle acupuncture in chronic TMD patients.
The selection of LNA as intervention for the treatment group is particularly appropriate, since the recent laser "needle" incorporates the advances in laser technology and also permits the precise stimulation of Classical acupoints' scheme of treatment. Acupuncture is a valid therapeutic tool for the management of different types of acute and chronic pain. However, it is characterized by many techniques and methods of stimulation, and possibilities of combinations of points, laying its foundation in the individualization of therapy in each single patient. For these reasons, scientific and clinical research in acupuncture is particularly difficult, presenting often several methodological deficiencies. Therefore, it is particularly interesting to utilize a multi-channel laser instrument, which allows the application of a standardized stimulation, but at the same time simultaneous, according to the principle of classical somatic acupuncture.
Second, in previous studies the TMD diagnostic criteria were ambiguous, or there was no distinction between acute and chronic disease, which made difficult to ensure homogeneity of the patient group. In our study, the patient' selection process is clear, it uses the standardized and validated DC/TMD diagnostic classification and involve the enrollment of only chronic patients, in order to form a precisely defined patient group.
Third, this study may allow to establish an LNA approach protocol for the patient with TMD pain, at least in the short term, and the results obtained may be used as a reference for future clinical trials of acute and subacute TMD or other musculoskeletal disease, as well as studies of other types of laser needle acupuncture.