Temporomandibular joint arthritis increases canonical Wnt pathway expression in the articular cartilage and trigeminal ganglion in rats

The canonical Wnt pathway participates in inflammatory diseases and it is involved in neuropathic pain. This study evaluated the immunoexpression of the canonical Wnt signaling pathway in the articular cartilage of the temporomandibular joint (TMJ) and along the nociceptive trigeminal pathway in arthritic rats. For this, male Wistar rats were divided into Control (C) and Arthritic (RA) groups. Arthritis induction was performed through subcutaneous injection of methylated bovine serum albumin (mBSA) and complete Freund Adjuvant (CFA)/ Incomplete Freund Adjuvant (IFA) on the first 14 days (once a week), followed by 3 weekly intra-articular injections of mBSA (10 μl/joint; left TMJ). The following parameters were evaluated: nociceptive threshold, inflammatory infiltrate, type I and III collagen birefringence, immunohistochemistry for IL-1β, TNF-α, IL-6, Wnt10b, β-catenin, cyclin-D1 in articular cartilage, c-Myc in synovial membrane, and immunofluorescence analysis for c-Fos, Wnt-10b and β-catenin in the trigeminal ganglion and the trigeminal subnucleus caudalis. The RA group showed intense articular cartilage damage with proliferation of type III collagen, increased immunoexpression of proinflammatory cytokines and Wnt-10b, β-catenin and cyclin-D1 in the articular cartilage and c-Myc in the synovial membrane. In the RA group, a reduction in the nociceptive threshold was observed, followed by a significant increase in the expression of Wnt-10b in neurons and β-catenin in satellite cells of the trigeminal ganglion. c-Fos immunoexpression was observed in neurons, peripherally and centrally, in arthritic rats. Our data demonstrated that TMJ arthritis in rats causes articular cartilage damage and nociceptive behavior, with increased immunoexpression of canonical Wnt pathway in the articular cartilage and trigeminal ganglion.

Botulinum Toxin in Facial Aesthetics Affects the Emotion Process: A Meta-analysis of Randomized Controlled Trials

This study aimed to conduct a meta-analysis of randomized controlled trials (RCTs) to evaluate the effects of the btulinum toxin-A (BT-A) in patiets with mood disorders. PubMed, Scopus, Web of Science, Cochrane Library and LILACS were searched without restrictions up to July 2022. The PICOS strategy was used for the selection of studies and risk-of-bias assessment was performed using Cochrane's tool for RCTs. RCTs were included if they compared BT-A treatment on facial muscles in patients with mood disorders to placebo. After assessment of the full texts, seven studies were selected. Five studies had low risk of bias for the generation of random sequence and blinding of participants and professional domains. A total of four studies showed a low risk of bias for the allocation concealment and blinding of the evaluation of the domain results. The domain of selective reports showed a low risk of bias in all included studies. However, four studies presented a high risk of bias for the domain of other biases. The meta-analysis was based on the mean difference or standardized mean difference between the BT-A and placebo groups for each selected trial and revealed that the BT-A group showed a significant improvement in the symptoms of depression when compared to placebo. This study revealed that the BT-A application into mimic muscles of the upper third of the face improves the mood disorders, but it was not possible to guarantee whether the aesthetic benefits can contribute to reducing the severity of the depressive state.

Anti-inflammatory and Hepatoprotective Effects of Quercetin in an Experimental Model of Rheumatoid Arthritis

Rheumatoid arthritis (RA) is an autoimmune disease characterized by inflammation in the joints. Although methotrexate (MX) is the first-line treatment, side effects are common. This study aimed to investigate the effects of quercetin (QT) and/or MX on inflammation and systemic toxicity in a rat model of RA. Male Wistar rats were divided into control (C), RA, QT, MX, and QT + MX groups (n=6). The RA induction consisted of three intra-articular injections of methylated bovine serum albumin (1×/week) in the temporomandibular joint (TMJ). QT (25 mg/kg) and/or MX (0.75 mg) administration occurred by oral gavage daily. We performed mechanical hyperalgesia in TMJ, leukocyte recruitment in synovial fluid, histopathology, and immunohistochemistry (TNF-α, IL-17, and IL-10) in synovial membrane and toxicity parameters. The RA showed a reduction in the nociceptive threshold (p<0.001), increase in leukocyte recruitment in synovial fluid (p<0.001), intense inflammatory infiltrate (p<0.001), and intense immunoexpression of TNF-α, IL-17, and IL-10 in the synovial membrane (p<0.001) compared to C (p<0.001). QT and/or MX therapy reduced inflammatory parameters (p<0.001). However, downregulation of IL-10 was observed only in the groups that received MX (p<0.001). Leukocytosis was seen in RA (p<0.05), but QT and/or MX reversed it (p<0.05). MX was associated with pathological changes in the liver and higher levels of transaminases when compared to the other groups (p<0.05). QT co-administered with MX reversed this hepatotoxicity (p<0.05). There were no alterations in the kidney between the groups (p>0.05). QT has potential to support MX therapy, showing anti-inflammatory and hepatoprotective effects in this model.

Effects of low-level laser therapy on the orthodontic mini-implants stability: a systematic review and meta-analysis

Objectives

The aim of this systematic review and meta-analysis was to assess the effects of low-level laser therapy (LLLT) on the orthodontic mini-implants (OMI) stability.

Materials and methods

An unrestricted electronic database search in PubMed, Science Direct, Embase, Scopus, Web of Science, Cochrane Library, LILACS, Google Scholar, and ClinicalTrials.gov and a hand search were performed up to December 2020. Randomized clinical trials (RCTs) or non-randomized clinical trials (Non-RCTs) that assessed the effects of LLLT on the OMI stability were included. Data regarding the general information, LLLT characteristics, and outcomes were extracted. The authors performed risk of bias assessment with Cochrane Collaboration’s or ROBINS-I tool. Meta-analysis was also conducted.

Results

Five RCTs and one Non-RCT were included and 108 patients were evaluated. The LLLT characteristics presented different wavelength, power, energy density, irradiation time, and protocol duration. Five RCTs had a low risk of selection bias. Two RCTs had a low risk of performance and detection bias. All RCTs had a low risk of attrition bias, reporting bias and other bias. The Non-RCT presented a low risk of bias for all criteria, except for the bias in selection of participants. The meta-analysis revealed that LLLT significantly increased the OMI stability (p < 0.001, Cohen’s d = 0.67) and the highest clinical benefit was showed after 1 (p < 0.001, Cohen’s d = 0.75), 2 (p < 0.001, Cohen’s d = 1.21), and 3 (p < 0.001, Cohen’s d = 1.51) months of OMI placement.

Conclusions

LLLT shows positive effects on the OMI stability.

Supplementary Information

The online version contains supplementary material available at 10.1186/s40510-021-00350-y.