When conservative treatments fail, hip osteoarthritis (OA), a chronic degenerative disease characterized by cartilage wear, progressive joint deformity, and loss of function, can result in the need for a total hip arthroplasty (THA). Surgical procedures induced tissue trauma and incite an immune response. Photobiomodulation therapy (PBMt) using low-level laser therapy (LLLT) and/or light-emitting diode therapy (LEDT) has proven effective in tissue repair by modulating the inflammatory process and promoting pain relief. Therefore, the aim of this study was to analyze the immediate effect of PBMt on inflammation and pain of patients undergoing total hip arthroplasty. The study consisted of 18 post-surgical hip arthroplasty patients divided into two groups (n = 9 each) placebo and active PBMt who received one of the treatments in a period from 8 to 12 h following THA surgery. PBMt (active or placebo) was applied using a device consisting of nine diodes (one super-pulsed laser of 905 nm, four infrared LEDs of 875 nm, and four red LEDs 640 nm, 40.3 J per point) applied to 5 points along the incision. Visual analog scale (VAS) and blood samples for analysis of the levels of the cytokines TNF-α, IL-6, and IL-8 were recorded before and after PBMt application. The values for the visual analog scale as well as those in the analysis of TNF-α and IL-8 serum levels decreased in the active PBMt group compared to placebo-control group (p < 0.05). No decrease was observed for IL-6 levels. We conclude that PBMt is effective in decreasing pain intensity and post-surgery inflammation in patients receiving total hip arthroplasty.

BackgroundTemporomandibular disorder (TMD) is described as a subgroup of orofacial pain with a set of signs and symptoms that involve the temporomandibular joint, masticatory muscles, ears, and neck. TMD can occur unilaterally or bilaterally and approximately 70% of the population is affected with at least one sign. The disorder progresses with orofacial pain, muscle pain involving the masticatory and cervical muscles, joint noises (clicks and pops), joint block, mandibular dysfunction, and headache. The etiology can be abnormal occlusion and/or posture, trauma involving local tissues, repetitive microtrauma, parafunctional habits, and an increase in emotional stress. Studies have demonstrated that phototherapy is an efficient option for the treatment of TMD, leading to improvements in pain and orofacial function.MethodsThe aim of the proposed study is to compare the effects of two sources of photobiomodulation in individuals with TMD. A randomized, controlled, double-blind, clinical trial is proposed, which will involve 80 individuals aged 18–65 years allocated to either a laser group or light-emitting diode (LED) group submitted to 12 sessions of phototherapy. The Research Diagnostic Criteria for TMDs will be used to evaluate all participants. Pain will be measured using the visual analog scale and maximum vertical mandibular movement will be determined with the aid of digital calipers.DiscussionThis study compares the effects of two modalities of laser therapy on the pain and orofacial function of patients with TMD dysfunction. Photobiomodulation and LED therapy are treatment options for reducing the inflammatory process and pain as well as inducing the regeneration of the target tissue.Trial registrationClinicalTrials.gov, NCT03257748. Registered on 8 August 2017.Electronic supplementary materialThe online version of this article (doi:10.1186/s13063-018-2444-7) contains supplementary material, which is available to authorized users.

Temporomandibular disorder (TMD) is described as a subgroup of orofacial pain. Studies have demonstrated that phototherapy is an effective treatment option for TMD, leading to improvements in pain and orofacial function. To compare the effects of photobiomodulation with different light sources on pain and functioning in patients with TMD. Methods: A randomized, controlled, double-blind clinical trial (pilot study) was conducted with 15 individuals aged 18 years or older allocated to two photobiomodulation groups: laser and LED. Sessions were held twice a week for four weeks (total: eight sessions). The Research Diagnostic Criteria for Temporomandibular Disorders were used for the evaluation and Pain was measured using the Visual Analog Scale. Orofacial function was determined based on measures of mandibular movements. Photobiomodulation was administered to the temporomandibular joint, masseter (upper, middle and lower) and anterior temporal muscles. Results: Statistically significant differences in pain were found in the intra-group analyses (pre-treatment vs. post-treatment) in both groups (laser: p=0.0117; LED: p=0.0180). Statistically significant intra-group differences were found for maximum mouth opening without assistance and maximum mouth opening with assistance in the laser group (p= 0.0203 and 0.0001, respectively). The same was found in the LED group only regarding maximum mouth opening with assistance (p=0.0459). Statistically significant intra-group differences (pre-treatment vs. post-treatment) were found for lateral excursion to both sides in the laser group (right side: p=0.0209; left side: p=0.0005) and only to the left side in the LED group (p=0.0342). Conclusion: Photobiomodulation with laser and LED produce similar effects regarding improvements in TMD.

After publication of our article [1] some questions were raised by a reader. We are grateful to the Editors-in-Chief for inviting Anne-Marie Glenny (Division of Dentistry, University of Manchester) to assess these questions, our responses and our published article. As a result we are publishing this Erratum to clarify various points. These are as follows: