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Objectives:: To present a method for image fusion of cone beam CT (CBCT)/CT and MRI and to explore whether the image data sets fused in such a way could aid the detection of temporomandibular joint (TMJ) anatomical structures and lesions., Methods:: There were five cases included in this study. One case was space occupying lesion giant cell tumour of tendon sheaths, one case was chronic inflammation in the condyle, one case was articular disc calcification of the bilateral TMJs, and the other two cases were TMJ disorders (anterior disc displacement without reduction). The digital imaging and communications in medicine format data of CT/CBCT and MRI of the cases were collected, and then imported to the Amira visual software where the registration process was conducted. Based on the different scan model, the registration process could be separated into automatic registration of CT/CBCT with quadrature slice MR images and the semi-automatic registration of CT/CBCT with oblique slice MR images by altering the registration parameters. Rigid transform model and the similarity metric of normalization mutual information was used for registration in the present study., Results:: The relationship between the soft mass and hard tissue was shown clearly in the fused images when compared to sole observation of CBCT/CT or MR images. The fused images could define the tumour outline and the destructive bone clearly in the same image. The fused results helped the observers to ensure uncertain defects which could not be confirmed only by one image data set., Conclusions:: The CT/CBCT and MR images could be fused to aid detection of TMJ anatomical structures and related lesions.

Objective: To investigate the association between single nucleotide polymorphisms (SNP) of ADAMTS14 gene rs4747096 and osteoarthritis of the temporomandibular joint in Chinese Han females., Methods: As a case-control study, a total of 213 Chinese Han females were involved in the present study, which contained 103 temporomandibular joint osteoarthritis patients and 110 healthy people who had no symptoms or signs of temporomandibular joint osteoarthritis as control. Peripheral blood samples were collected from each participant. Genomic DNAs of temporomandibular joint osteoarthritis patients and healthy control were extracted from peripheral venous blood, which were stored in -80 °C refrigerator by using DNA extraction kits. The designed primers were used for polymerase chain reaction (PCR) amplification of specific DNA fragments. Genotype was determined by sequencing the PCR products. The software Chromas 2.22 was used to analyze the genotype. The genotype distributions, allele frequencies and genetic models between the patients and controls were compared. The age distribution was checked by t-test. Genotype and allele frequency were detected by Chi-square test., Results: In the present study, there were no significant differences between the osteoarthritis patients and healthy controls in terms of age. The genotype distribution was in accordance with Hardy-Weinberg equilibrium in the two groups. The genotype frequency of the ADAMTS14 (rs4747096) in the experimental group was 38.8% (AA), 55.4% (AG), and 5.8% (GG), respectively. The genotype frequency in the control group was 40.9% (AA), 43.6% (AG), and 15.5% (GG), respectively. The difference of genotype frequency of the ADAMTS14 (rs4747096) was significant between the experimental group and the control group (P=0.047). There was no significant difference in allele frequency between the two groups (P=0.415). AA and AG genotypes significantly increased the risk of the disease compared with GG in dominant model (OR=1.114, 95% CI: 1.015-1.223, P=0.028)., Conclusion: A significant correlationship was found between the ADAMTS14 (rs4747096) SNP and the temporomandibular joint osteoarthritis in Chinese Han females. The distribution of rs4747096 may be different between temporomandibular joint osteoarthritis and healthy population.

Objective: Temporomandibular joint osteoarthritis (TMJOA) is a complex disease with strong genetic and epigenetic components in its pathogenesis. The aim of this study was to evaluate DNA methylation in mandibular head cartilage in different phases of experimentally-induced TMJOA in rats., Design: DNA methylation was evaluated using microarrays in the mandibular head cartilage of early, intermediate and late stage experimentally-induced TMJOA, and of the normal age-matched control groups. Genes with differentially methylated CpG sites were analyzed to reveal the over-represented gene ontologies and pathways at different stages, and were compared with published expression profiles to assess their overlappings. The DNA methylation patterns of the target genes were validated by methylated DNA immunoprecipitation qPCR in additional independent cartilage samples and mRNA levels were analyzed by real-time PCR., Results: We observed 9489 differentially methylated regions between the TMJOA and controls. A total of 440 consistently altered genes were revealed in all three stages; most (80%) were hypomethylated and many were associated with cell cycle regulation. We also detected different DNA methylation changes in early and late stage TMJOA (Rearly=0.68, Rlate=0.47), while the differences between age-matched healthy cartilage were subtle. Strong inverse changes between methylation status and mRNA levels were confirmed in Adamts5, Chad, Cldn11 and Tnf., Conclusions: Our data reveals dynamic DNA methylation patterns during the progression of TMJOA, with a different host of genes and pathways. The changes of cartilage DNA methylation patterns might contribute to understand the etiologic mechanisms of TMJOA epigenetically., (Copyright © 2016 Elsevier Ltd. All rights reserved.)

Objective: We have previously reported that interleukin-1β (IL-1β) up-regulates the expression of Wnt-5A and the activation of Wnt-5A signaling induces matrix metalloproteinase (MMP) through the c-Jun N-terminal kinase pathway in condylar chondrocytes (CCs) of the temporomandibular joint (TMJ). These results suggest that Wnt-5A could play an essential role in IL-1β-mediated cartilage destruction. The objective of this study was to investigate the molecular mechanism underlying IL-1β-induced up-regulation of Wnt-5A in TMJ CCs., Methods: Primary CCs, limb chondrocytes (LCs) and SW1353 human chondrosarcoma cells were treated with IL-1β in the presence or absent of BAY 11-7082 (an inhibitor of IκBα-phosphorylation). Then, expression of Wnt-5A was estimated by real-time reverse transcriptase-polymerase chain reaction (RT-PCR), Western blotting and immunocytofluorescence. Transient transfection of p65 expression vector and chromatin immunoprecipitation (ChIP) assay was performed to define the effect of p65 on Wnt-5A expression., Results: IL-1β up-regulated Wnt-5A expression at both the RNA and protein levels in articular chondrocytes. The inhibitor of IκBα-phosphorylation, BAY 11-7082, blocked the induction of Wnt-5A by IL-1β in a dose-dependent manner. Moreover, experiments with overexpression of p65 and ChIP established that induction of Wnt-5A by IL-1β is mediated through the NF-κB pathway, especially the p65 subunit., Conclusion: These results clarify the molecular mechanism underlying up-regulation of Wnt-5A by IL-1β in chondrocytes, suggesting an important functional crosstalk between Wnt-5A and NF-κB signaling pathways. This finding provides new insights into the involvement of Wnt signaling in the cartilage destruction caused by arthritis., (Copyright © 2010 Osteoarthritis Research Society International. Published by Elsevier Ltd. All rights reserved.)

Objective: To investigate the types of disc position of the temporomandibular joint (TMJ) and their relationship with age and gender in asymptomatic volunteers by magnetic resonance imaging (MRI)., Methods: A total of 100 asymptomatic volunteers were divided into 5 groups (11-, 21-, 31-, 41-, 51 - 60 years old), 10 male and 10 female were included in each group. A total of 200 TMJs were scanned with Siemens Trio Tim 3.0T MRI system oblique-sagittally at closed- and open-mouth positions. Visual evaluation of MR images were performed on 3 neighbour slices of each TMJ (lateral, central, medial)., Results: There was a normal disc-condyle relationship in 59 of the 100 asymptomatic subjects. The normal disc position, anterior disc displacement and insidious anterior disc displacement (IADD) were observed in 140 (70.0%), 14(7.0%) and 46(23.0%)joints respectively, which showed no significant differences among different age groups or between genders (P > 0.05). The maximum mouth opening of the 100 asymptomatic volunteers was (46.3 +/- 5.5) mm, with no significant difference among the various types of disc position (P > 0.05)., Conclusions: Disc displacement does exist in the asymptomatic volunteers, however, its occurrence is not associated with age and gender. IADD is the main type of the disc displacement in asymptomatic volunteers. There is no close relationship between the imaging manifestation of the disc displacement and clinical symptoms.

Background: Over 70% of the total tissue weight in the cartilage matrix consists of water, and the early-stage osteoarthritic cartilage is characterized by swelling. Water transport in the cartilage matrix and across the membranes of chondrocytes may be important in normal and pathological conditions of cartilage. The purpose of this study was to identify aquaporin-1 (AQP1) and aquaporin-3 (AQP3) expressions in the mandibular condylar cartilage after experimentally induced osteoarthritis (OA) in rats., Methods: An experimental temporomandibular joint OA was induced by partial discectomy in rats. The pathological characteristics of the normal, early-stage, and late-stage osteoarthritic TMJ cartilages were verified by histological techniques. The AQP1 and AQP3 gene expressions in the normal and osteoarthritic cartilages were measured using quantitative real-time reverse-transcription PCR analysis. The cartilage sections were incubated in primary polyclonal antibodies to AQP3; immunofluorescent microscopy was used to examine the AQP3 expression shown by its protein level., Results: The mRNA expression levels of AQP1 and AQP3, analyzed using quantitative PCR, revealed that AQP3 mRNA was highly up-regulated in the OA cartilage, which was considered significant. There was no notable difference in the expression of AQP1 mRNA between OA and normal controls. With the progressing of the OA, the localization of the AQP3 protein was quite different from that of the normal cartilage. Compared to the normal cartilage, the expressions of AQP3 protein were observed mainly in the proliferative zone and the upper mid-zone chondrocytes at the early-stage of OA, and were observed to appear frequently throughout the mid- and deep zone during the late-stage of OA., Conclusions: The high expression of AQP3 mRNA in the OA cartilage and the different localization of the AQP3 protein suggest that it may play a particular role in OA pathogenesis. Further study of AQP3 function may provide new insight into the understanding of the molecular mechanisms underlying OA.