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Our purpose was to measure the temporomandibular joint (TMJ) synovial fluid (SF) levels of vascular endothelial growth factor (VEGF) and fibroblast growth factor-2 (FGF-2) before and after intra-articular injection of hyaluronic acid (HA) and to investigate the possible mechanism involved in the therapeutic value of HA. We analysed the synovial fluid of 30 patients with unilateral internal derangement (ID) or osteoarthritis (OA) of the TMJ (confirmed by magnetic resonance imaging and cone-beam computed tomography) and recorded clinical signs and symptoms including maximal mouth opening, subjective joint pain, and joint noise at the patient's each visit. All clinical signs significantly improved after injection of HA, and there was no significant difference between ID and OA groups. In synovial fluid parameters, the concentration of VEGF was significantly higher before treatment with HA than after treatment, but there was no significant difference in the concentration of FGF-2 between before and after treatment. The study findings suggest intra-articular injection of HA may reduce the synovitis and improve the internal state of the TMJ in a short period.

The abundance of inflammatory mediators in injured joint indicates innate immune reactions activated during temporomandibular joint osteoarthritis (TMJOA) progression. Toll‐like receptor 4 (TLR4) can mediate innate immune reaction. Herein, we aimed to investigate the expression profile and effect of TLR4 in the cartilage and subchondral bone of the discectomy‐induced TMJOA mice. The expression of TLR4 and NFκB p65 in the synovium of TMJOA patients was measured by immunohistochemistry, Western blotting and RT‐PCR. H&E and Masson staining were utilized to assess the damage of cartilage and subchondral bone of the discectomy‐induced TMJOA mice. A TLR4 inhibitor, TAK‐242, was used to assess the effect of TLR4 in the cartilage and subchondral bone of the discectomy‐induced TMJOA mice by Safranin O, micro‐CT, immunofluorescence and immunohistochemistry. Western blotting was used to quantify the expression and effect of TLR4 in IL‐1β–induced chondrocytes. The expression of TLR4 and NFκB p65 was elevated in the synovium of TMJOA patients, compared with the normal synovium. TLR4 elevated in the damaged cartilage and subchondral bone of discectomy‐induced TMJOA mice, and the rate of TLR4 expressing chondrocytes positively correlated with OA score. Intraperitoneal injections of TAK‐242 ameliorate the extent of TMJOA. Furthermore, TLR4 promotes the expression of MyD88/NFκB, pro‐inflammatory and catabolic mediators in cartilage of discectomy‐induced TMJOA. Besides, TLR4 participates in the production of MyD88/NFκB, pro‐inflammatory and catabolic mediators in IL‐1β–induced chondrocytes. TLR4 contributes to the damage of cartilage and subchondral bone in discectomy‐induced TMJOA mice through activation of MyD88/NFκB and release of pro‐inflammatory and catabolic mediators.

Purpose Coronoidectomy is carried out frequently as a part of the cranial-maxillofacial surgery procedure. There are few articles on the fate of coronoid process after coronoidectomy, except that several case reports mentioned that coronoid process had regenerated. This study aimed to radiographically access the anatomic outcomes of coronoid process and investigate which factors were associated with the outcomes after coronoidectomy. Materials and Methods A retrospective cohort study included patients undergoing coronoidectomy over a 7-year period. The primary outcome variable was the new coronoid process occurrence (yes/no). Secondary outcome variable was the type of the new coronoid process by evaluating its size, shape and position. Radiograph at 1-year postoperative visit was used to determine the outcomes. The predictor variables included age, sex, surgical purpose, surgical side, surgical approach and the maximal interincisal opening. Appropriate statistics were analyzed by SPSS version 22. χ2 test and binary logistic regression were used to assess the association between predictor factors and anatomic outcomes (P Results The study sample included 57 patients. In total, 96 coronoidectomies were performed. Seventy-four coronoid processes (77.1%) showed complete (n = 44, 45.8%), nonunion (n = 19, 19.8%) or partial (n = 11, 11.5%) regrowth, whereas no evidence of regeneration in 22 sites was observed radiographically at 1-year postoperative visit. Binary logistic regression showed that a young age (odds ratio 0.704; 95% confidence interval 0.562-0.882; P = .002) was significantly associated with regeneration of coronoid process. Conclusions Coronoid process can mostly regenerate after coronoidectomy. A young age may contribute to regrowth of coronoid process.

Background Synovial chondromatosis (SC) of temporomandibular joint (TMJ) occupies 3% SC cases. In other joints like hip and knee which were composed hyaline cartilage (HC), loose bodies (LBs) were reported to be a HC feature. However, condyle surface and disc in TMJ are fibrous cartilage (FC). Therefore, we proposed a different pathogenesis of TMJSC. Methods LBs and synovium were collected from seven TMJSC patients, and histological and immunohistological examinations were performed. Results Three ways of HC formation were discovered: regular-shaped cartilaginous nodules (CNs) in sublining layer (SL) of vascularized synovium, regional chondrification of SL, and finger-like tissue with a tail attaching to synovium. Detached LBs could fuse and were only positively stained by aggrecan. Without synovium attachment to LBs, fused LBs remained a hyaline extracellular matrix (ECM). However, after synovium attachment, transformation from HC to FC occurred. Two types of FC were observed. First type FC was featured by vertical-distributed type I collagen fibers imbedding few chondrocytes, suggesting mature phase with superior mechanical features. Second type FC was featured by medium-density chondrocytes with type I collagen and aggrecan-positive ECM, suggesting primary phase. The transformation process started in appearance of 2nd type FC deriving from synovium covering LB, and gradually replaced HC from periphery to center. Conclusions Three ways of HC formation were closely related. Different with SC in other joints, hyaline ECM in LBs of TMJSC could be replaced by FC deriving from synovium, during which 2nd type FC first replaced HC and then transformed to 1st type FC.

Our aim was to evaluate the efficacy of high condylectomy combined with orthodontic treatment for active unilateral condylar hyperplasia in 25 affected patients, by an analysis of the maxillary and mandibular changes on cone-beam computed tomography (CT). High condylectomy was the sole operative treatment. Variables that reflected the canting of the occlusal plane, the height of the maxillary complex, the buccolingual angulation of the maxillary first molar, the height of the ramus, the total length of the mandible, and the deviation of the chin were measured and compared between the two sides and between time intervals: preoperatively (T1) and the end of treatment (T2). The differences between time intervals in the deviation of the chin (p

Summary Objective This study aimed to screen differential expression of microRNAs (miRNAs), and investigate function of the specifically selected miRNA in synovial fibroblasts from patients suffering osteoarthritis of temporomandibular joint (TMJOA). Methods MiRNA microarray was used to select differentially expressed miRNAs between TMJOA and normal synovial fibroblasts. The expression of screened miRNA221-3p was quantified using real-time PCR, and its specific target gene was predicted by bioinformatics. After transfection of miRNA221-3p mimics or inhibitor into synovial fibroblasts, the expression of v-Ets avian erythroblastosis virus E26 oncogene homolog 1 (Ets-1) was detected by immunohistochemistry, real-time PCR and Western blot, respectively. Dual luciferase activity was performed to identify the direct regulation of miRNA221-3p on Ets-1. Interlukin-1β (IL-1β) mimics an inflammatory situation. Results In TMJOA synovial fibroblasts, eight miRNAs were up-regulated and six miRNAs were down-regulated. MiRNA221-3p was the most down-expressed. A sequence in the 3′-untranslated (3′-UTR) of Ets-1 complementary to the seed sequence of miRNA221-3p. Elevated expression of Ets-1 associated with attenuation of miRNA221-3p. Over-expression of miRNA221-3p suppressed the activity of a reporter construct containing the 3′-UTR of Ets-1 transcript and inhibited the expression of Ets-1 as well as its downstream molecules, matrix metalloproteinase 1 (MMP1) and MMP9 in TMJOA synovial fibroblasts. IL-1β suppressed the expression of miRNA221-3p in both a dose-dependent and time-dependent manner. Conclusion The reduction of miRNA221-3p in synovial fibroblasts, attributed from abundance of IL-1β in inflamed circumstance, induces Ets-1 up-regulation and then, initiates MMP1 and MMP9 secretion, thereby leading to continuously pathological development in TMJOA.

Radiofrequency thermocoagulation (RFT) is used widely for the treatment of idiopathic trigeminal neuralgia (TN). Precise puncture and placement of the electrode needle tip are crucial for successful RFT. This technical note introduces a novel method for performing RFT using a customized, three-dimensionally (3D)-printed guide plate. Eleven patients with idiopathic TN were treated using this method between February and July 2016. Three had V2 branch TN and eight had V3 branch TN. Punctures in eight patients were successful at the first attempt; slight adjustments were required subsequently in the other three patients. The puncture time in all cases was less than 1 min. The patients reported pain relief immediately after RFT, and no complications were observed in any patient. Thus, the customized 3D-printed guide plate offers the advantages of precise placement of the puncture needle and minimal complications.

Background Temporomandibular joint (TMJ) osteoarthritis(OA)characterized with cartilage degen-eration is associated with inflammation. High mobility group box chromosomal protein-1(HMGB-1)is a potent mediator of inflammation and the trigger of OA. The expression of HMGB-1 in TMJ OA was uncovered, but the role of HMGB-1 in TMJ cartilage degeneration is not fully understood. In this study, the regulation of HMGB-1 in TMJ condylar cartilage was revealed. Methods A complete Freund's adjuvant (CFA)-induced TMJ inflammation animal model was employed and the expression of HMGB-1 was detected at 1st, 2nd, and 6th weeks by immunohistochemistry. TMJ condylar chondrocytes were incubated with IL-1β (10 and 40 ng/ml) at 24, 48, and 72 h, and the translocation and protein level of HMGB-1 were evaluated by immunofluorescence and Western blot. Result Nuclear HMGB-1 staining was predominantly located in chondrocytes of both the fibrosis and proliferative zones in healthy TMJ. 1st week and 2nd week after CFA injection, immunoreaction could be detected in the cytoplasms of HMGB-1-positive cells and cartilage matrix especially in hypertrophic zone. At 6th week after CFA injection, cartilage matrix expression was disappeared and the cytoplasm expression of HMGB-1 was very weak in hypertrophic zone. HMGB-1 was translocated from the nucleus to the cytoplasm at 48 h after incubated with IL-1β (10 ng/ml and 40 ng/ml). The protein level of HMGB-1 was increased after stimulation and had a peak at 48 h. Conclusion HMGB-1 might be associated with TMJ inflammation and OA. Insight into the role of HMGB-1 in TMJ inflammation is helpful to add the new knowledge into the pathogenesis of TMJ OA.

Summary Objective This study aimed to explore potential microRNAs (miRNAs), which participate in the pathological process of condylar hyperplasia (CH) through targeting specific proliferation- and apoptosis- related genes of chondrocytes. Methods Insulin-like growth factor 1 (IGF1), IGF1 receptor (IGF1R) and B-cell CLL/lymphoma 2 (BCL2) in CH cartilage were detected by real-time polymerase chain reaction (PCR), Western blot, immunohistochemistry and immunofluorescence. MiRanda and TargetScanS algorithms were used to predict certain miRNAs in CH chondrocytes concurrently modulating the above three genes. MiR-15b was screened and identified using real-time PCR. After transfection of miR-15b mimics or inhibitor into CH chondrocytes, expression of the above three genes was detected by real-time PCR and western blot, meanwhile, cell proliferation and apoptosis was examined by CCK8, cell cycle assays, flow cytometry and Hoechst staining. Dual luciferase activity was performed to identify the direct regulation of miR-15b on IGF1, IGF1R and BCL2. Results Expression of IGF1, IGF1R and BCL2 increased in CH cartilage. Seven microRNAs concurrently correlated with IGF1, IGF1R and BCL2. Among them, only miR-15b significantly changed in CH chondrocytes. Overexpression of miR-15b in CH chondrocytes suppressed the expression of IGF1, IGF1R and BCL2, while it increased when miR-15b was knockdown. Furthermore, miR-15b suppressed their expression by directly binding to its 3′-UTR in these cells. Besides, miR-15b hampered chondrocytes proliferation through targeting IGF1 and IGF1R and accelerated chondrocytes apoptosis through targeting BCL2. Conclusion Suppressed miR-15b contributed to enhanced proliferation capacity and weakened apoptosis of chondrocytes through augmentation of IGF1, IGF1R and BCL2, thereby resulting in development of CH.

The aim of this study was to explore the application and efficacy of personalized digital guiding plate-aided radiofrequency in treating trigeminal neuralgia (TN). A total of 117 cases (93 patients) of TN from January 2015 to December 2016 were divided into the study group (n = 53) and the traditional group (n = 64). Patients in the study group were treated by the radiofrequency through a personalized digital guiding plate, whereas those in the traditional group were treated by the traditional method. We found that no significant difference between these 2 groups in age, sex, and divisions affected (V2, V3). However, the values for operation time, recurrence rate, and patient's satisfaction in the plate assisted group were significantly improved compared with those in the traditional group. Therefore, the personalized digital guiding plate-assisted radiofrequency has higher application value than traditional method.

Objective: Temporomandibular disorder causes the dysfunction of fibroblast-like synoviocytes (FLSs) which are predominant in the lining layer (LL) of synovial membrane (SM) and responsible for the secretion function of the SM of the temporomandibular joint (TMJ). This study aimed to construct a triple-layered cell sheet (CS) for tissue-engineering the SM. Methods: FLSs were harvested and identified immunocytochemically. A triple-layered CS was fabricated by an original method of combining type I collagen and FLSs. Staining and a transmission electron microscope were used to compare the morphological similarities between the CS and the natural LL. Hyaluronic acid (HA) production and HA synthase 2 (HAS2) gene expression were assessed by ELISA and PCR, respectively. Transplantation of triple-layered CSs into nude mice was performed and examined by staining and immunohistochemical methods. Results: FLSs expressed vimentin, CD44 and heat shock protein 27. The triple-layered CS possessed a structure similar to natural LL. No tight conjunction was observed between adjacent FLSs. The triple-layered CS secreted HA at a quantity about 3 times that of the single-layered CS. The triple-layered structure induced higher expression of HAS2 in FLSs. No difference in HAS2 expression between the triple-layered CS and natural SM was observed. Multiple-layered FLSs and invasion of host fibroblasts and vessels were observed 2 weeks after transplantation. HAS2 and HA were expressed in surface cells and extracellular matrix, respectively. Conclusion: FLSs of the TMJ were type B synoviocytes. The triple-layered CS mimicked natural SM morphologically and functionally. The CS survived for 2 weeks in vivo. Therefore, triple-layered CS might be highly competent for tissue-engineered SM.

Temporomandibular joint (TMJ) ankylosis with facial asymmetry is still controversial to deal with. This study describes a modified condylar distraction osteogenesis protocol via preauricular approach for the treatment of this condition.From 2006 to 2013, 18 patients with TMJ ankylosis were enrolled. The Wuhan TMJ Ankylosis treatment protocol includes as follows: (1) preauricular approach is the only surgical access; (2) TMJ arthroplasty is used to recontour the condylar head, and the vertical height of condyle is maintained; (3) distractor placement with distractor port exiting via preauricular incision; (4) distraction after 5 to 7 days of latency period with 0.5 mm twice daily; and (5) distractor removal after 3-month consolidation through preauricular incision. All patients had clinical follow-up and detailed examination.All patients had satisfactory results postoperatively. The mean (range) mouth opening increased from 7.1 (0-18) to 32.1 (28-43) mm during 37 (6-81) months of follow-up period (P0.01). Facial asymmetry was corrected in all patients, and all patients had minimal postoperative scar perception of the preauricular incision.The Wuhan TMJ ankylosis protocol provides a safe and effective treatment alternative in managing TMJ ankylosis, especially in young women who are anxious about perceptive extraoral scar.

Osteochondroma is one of the most common benign bone tumors, but it is rare in the mandibular condyle. The purpose of this study was to increase the clinical and radiographic cognition of osteochondroma in the mandibular condyle. Thirty-four patients with radiographic and pathologic features of unilateral condylar osteochondroma were included in this retrospective study. All cases received clinical and radiographic examinations before tumor resection. Common manifestations included facial asymmetry, hypomobility, malocclusion, joint dysfunctions, and even external auditory canal stenosis. Osteochondroma might arise on the different condylar areas, such as the medial aspects (55.9%), anterior-superior (11.8%), posterior-superior (11.8%), lateral (8.8%), and generally enlarged (11.8%). The tumor formed a pseudojoint under the anterior eminence in 55.9%; the affected mandible presented normal shape in 58.8%; and horizontal mandibular deviation was caused by the tumor or elongated ramus in 70.6%. The condylar osteochondroma may locate in different positions encircling the condyle, which increases recognition and diagnosis of these lesions.

Purpose The rabbit model has been established to mimic the effect of temporomandibular joint (TMJ) arthroplasty of ankylosis, and distraction at the level of the condylar neck is used to elongate the ascending ramus. The histomorphologic changes of TMJ and distraction gap were investigated. Materials and Methods The unilateral condyles and articular discs were extirpated, and the experimental mandibular rami were shortened by 5 mm. An embedded distracter was used to restore the height of the mandibular ramus by unilateral condylar neck distraction (0.8 mm daily for 7 days). A total of 12 adult white rabbits were used, 8 in the experimental group and 4 in the control group. Of the 8 rabbits in the experimental group, 4 each were killed at 4 and 8 weeks after completion of distraction. The TMJ and distracted calluses were harvested and processed for radiographic and histologic examination. Results An open bite was seen in all rabbits postoperatively that had diminished at the end of distraction. The newly formed condyles radiologically showed remodeling, flattening, and sclerosis. The bony transport disc had gradually remodeled to a new condyle that was similar to the original condyle in appearance and structure. The surface of the transport disc was covered with a fibrous tissue. Moreover, the bony regeneration was perfect in the distraction gap. Conclusion These results suggest that distraction osteogenesis at the condylar neck using the traditional preauricular approach of TMJ surgery, without the additional incision, can be performed concurrently with arthroplasty of TMJ ankylosis at the same region.

Background A high density of blood vessels is observed in the perforated disks of temporomandibular joint (TMJ), but the underlying mechanism is unknown. This study aimed to explore the regulation of disk angiogenesis in the perforated disks. Methods Expressions of vascular endothelial growth factor (VEGF), angiogenin-1 (Ang-1), chondromodulin-1 (ChM-1), and thrombospondins-1 (TSP-1) were compared between healthy and perforated TMJ disk cells with or without interleukin-1β (IL-1β) incubation. The tube formation, cell migration, and expressions of matrix-metalloproteinases (MMPs) in human umbilical vein endothelial cell line (HUV-EC-C) were investigated in conditional media of disk cells. Western blot was performed to determine protein level of VEGF, Ang-1, ChM-1 and TSP-1 in IL-1β-induced disk cells cultured by NF-κB- or P38-specific pathway inhibitors, respectively. Results Conditional media from perforated disk cells induced more tube formation, cell migration, and MMPs’ expression in HUV-EC-C. Expressions of VEGF and Ang-1 were significantly higher, and ChM-1 and TSP-1 were lower in perforated disks compared to healthy disks. The VEGFA concentration was 291.1 ± 36.09 pg/ml in perforated disk cell conditioned media, markedly larger than that in NDCCM (144.9 ± 33.69 pg/ml). IL-1β induced VEGF through NF-κB signaling pathway and Ang-1 through p38 MAPK pathway, while repressed expression of ChM-1 and TSP-1 was through NF-κB pathway. Blockade of each pathway markedly restrained inducing effect of cultural media on HUV-EC-C tube formation and migration. Conclusions Perforated disk cells secreted more angiogenic factors which might induced via NF-κB pathway.

Purpose The retrospective study evaluated long-screw (bicortical screw) osteosynthesis used in the surgical treatment of sagittal fracture of the mandibular condyle and compared it with titanium plates and removal of the condylar fragment. Patients and Methods Ninety-five patients with sagittal fracture of the mandibular condyle received open surgical treatment from 1997 to 2008. Among these patients, the condylar fragments were fixed with long screws in 56 cases (group A), were fixed with titanium plates in 12 cases (group B), and were completely removed in 24 cases (group C). Follow-up was carried out clinically and radiologically. The clinical features included limitation of mandibular mobility, occlusion disturbance, lateral deviation on mouth opening, joint pain, clicking, facial asymmetry, and patient's subjective evaluation. The radiologic parameters consisted of degree of bony resorption, bony change, change of osteosynthesis material, and shortening of mandibular ramus height. Results Anatomic reduction and functional restoration were obtained and no severe complication was detected in group A. However, 3 of 14 patients had severe osteoarthrosis and 2 of 14 patients had ankylosis in group B. In group C 3 of 24 patients had mandibular retrusion, 4 of 24 patients had front teeth open bite, 4 of 24 patients had severe osteoarthrosis, and 1 of 24 patients had ankylosis. Conclusion The long-screw fixation group had a more favorable prognosis than the titanium plate group and the group in which removal of the condylar fragment was performed. The long-screw fixation technique might be suitable for use in the surgical treatment of sagittal fractures of the mandibular condyle.

Condylar hyperplasia is a complex post-natal growth abnormality of the mandible and condyle, which leads to facial asymmetry. We investigated the distributions of insulin-like growth factors (IGF-1), bone morphogenetic protein-2 (BMP-2) and transforming growth factor-β1 (TGF-β1) in cartilage of condylar hyperplasia and revealed relationships between age and the cartilaginous thickness. Twenty patients with condylar hyperplasia were divided into four histopathological types. The cartilaginous thickness and age in different histological types were analysed, and the localizations of IGF-1, BMP-2 and TGF-β1 were detected by immunohistochemistry analysis. The cartilaginous thickness of condylar hyperplasia significantly increased. The cartilaginous thickness of type III was significantly thicker than type I and type II, Bivariate correlation revealed a significant correlations between age and the cartilaginous thickness (r = 0·68, P = 0·01). However, the expressions of IGF-1, BMP-2 and TGF-β1 were the strongest in type I. In almost all types of condylar hyperplasia, the presence of IGF-1 and BMP-2 was found mainly in the proliferative chondrocyte layer and the hypertrophic chondrocyte layer, and only a few in the calcified chondrocyte layer. The presence of TGF-β1 widely distributed from the fibrous articular surface to the calcified cartilage. These findings suggest that the proliferative activity of cartilage in condylar hyperplasia is strongly associated with age and cartilaginous thickness. Therefore, the four pathological types of condylar hyperplasia seem more likely to be four discontinuous stages.

The collapse of lubrication function caused by changes of synovial fluid (SF) is regarded as the main aetiology of temporomandibular disorders (TMD). Hyaluronan (HA) is one of the principal components of SF. Both physicochemical properties and cell biological functions of HA mainly depend on its molecular size. The present study was designed to analyse the HA molecular size and boundary-lubricating ability of SF in the patients with TMD and compare them with that from normal controls. Temporomandibular disorders patients were divided into three subgroups: displaced disc with reduction (DDR), disc without reduction (DDNR) and disc perforation (DP). After obtaining SF samples, we analysed the molecular size of HA by high-performance liquid chromatography, and boundary-lubricating ability (coefficient of friction, COF) of SF by a friction apparatus. The results suggested that there was no significant difference in molecular size of HA among the groups of health control, DDR and DDNR, while the DP group presented a lower molecular size when compared to other ones. Boundary-lubricating ability test showed that COF of SF in TMD patients were significantly higher than that of healthy controls. In the patients' subgroups, no statistical difference was observed between the group of DDR and DDNR, while DP group presented a higher COF when compared to the group of DDR or/and DDNR. Collectively, the increased values of COF, which corresponded to the decrease of HA molecular size, indicated that the distinct changes of HA molecular size and boundary-lubricating ability in the SF occurred with TMD.

Different approaches to the mandibular condyle have been described. In this paper, a modified trans-oral technique to access the mandibular condyle is described and illustrated. This technique was used in a small group of patients; the clinical outcomes are promising. The technique can be used in various temporomandibular joint (TMJ) operations, such as condylar resection, high condylectomy or tumor removal. It provides adequate intra-oral surgical access to the mandibular condyle and avoids complications from extra-oral approaches to the TMJ.

To compare the outcome of inferior and superior joint space injection of sodium hyaluronate in patients with disc displacement without reduction of the temporomandibular joint (TMJ).One hundred twenty patients with disc displacement without reduction of TMJ were randomized into 2 experimental groups. One group of patients received superior joint space injections of sodium hyaluronate and the other group was treated with inferior joint space injections. Patient's TMJ status and clinical symptoms were evaluated at the 3 and 6 month follow-up appointments. The clinical parameters recorded were maximal mouth opening (MMO), pain intensity on a visual analog scale (VAS), and modified Helkimo's clinical dysfunction index and analyzed with ANCOVA.Fifty of the superior and 54 of the inferior joint space injection therapy group returned for the 3 and 6 month evaluations; 86.67% of the patients were retained in the follow-up. MMO, VAS, and Helkimo's index of both groups improved at the 3 and 6 month follow-ups. The results of MMO changes and TMJ function were almost the same in both groups at 3 month follow-up. However, there was a significant reduction in TMJ pain in the inferior joint injection group at 3 month follow-up compared with the superior joint injection group (P.001). There were also significant differences between the inferior joint injection group and superior joint injection group in MMO (P.005), VAS (P.001), and Helkimo's index (P.001) at 6 month follow-up.This study showed that inferior joint space injection with sodium hyaluronate is a valid method of treating disc displacement without reduction of TMJ and a long-term study will be needed to assess the effect of inferior joint injection on the morphologic changes of the TMJ.

Molecular epidemiological research suggests that interleukin-10 (IL-10) polymorphisms may be associated with an increased risk of head and neck cancer (HNC), but results remain controversial. To derive a more precise evaluation, we performed a meta-analysis focused on genetic polymorphisms of IL-10. PubMed, Embase, CNKI and Wanfang databases were searched for studies that examined the relationship between IL-10 polymorphisms or haplotypes and HNC risk. The odds ratio (OR) and 95% confidence interval (CI) were applied to assess the relationship strength. Publication bias, sensitivity and cumulative analyses were conducted to measure the robustness of our findings. Overall, nine related studies involving 2,258 patients and 2,887 control samples were analyzed. Significant associations between the IL-10-1082A > G polymorphism and HNC risk were observed (G vs. A: OR = 1.56, 95% CI = 1.27–1.92, P 2 = 69.4%; AG vs. AA: OR = 1.64, 95% CI = 1.32–2.05, P 2 = 55.6%; GG vs. AA: OR = 2.24, 95% CI = 1.69–2.97, P 2 = 38.5%; AG + GG vs. AA: OR = 1.70, 95% CI = 1.36−2.14, P = 0.02, I2 = 61.8%; GG vs. AA + AG: OR = 1.89, 95% CI = 1.23−2.90, P = 0.01, I2 = 46.3%) in the total population, as well as in subgroup analysis. Moreover, increased HNC risks were also associated with the IL-10 −819T > C polymorphism and the GCC haplotype. In conclusion, our meta-analyses suggest that IL-10 polymorphisms, specifically the −1082A > G polymorphism, may be associated with increased risk of HNC development.

Synovial chondromatosis (SC) of temporomandibular joint is rare proliferative disorder featured by the formation of cartilaginous nodules in synovium and joint space. Transforming growth factor beta 3 (TGF-β3) is closely related to chondrogenic differentiation and might participate in pathogenesis of SC. We discovered that increased quantity of synoviocytes and blood vessels were observed in SC synovium. The vessel wall and sublining fibroblasts were stained positively by the antibodies against TGF-β3, fibroblast growth factor 2 (FGF-2) and CD34. In loose bodies (LBs), TGF-β3 was mainly expressed in chondrocytes and FGF-2 was expressed in chondrocytes, fibroblasts and vessel walls. Expressions of TGF-β1, TGF-β3, FGF-2, Sox9, Wnt-4, Foxc2 and VEGF-A mRNA were significantly higher in SC synovium. Stimulation of TGF-β3 on synoviocytes increased alkaline phosphatase (ALP) activity and expressions of chondrogenic genes (Sox9, Col2α1, Aggrecan, Wnt-4 and Wnt-11), osteogenic genes (Runx2, Foxc2, osteocalcin and Col1α1) and VEGF-A, but failed to influence FGF-2 expression. However, the addition of FGF-2 increased TGF-β3 expression. In conclusion, TGF-β3 existed in synovium and LBs of SC and was responsible for the pathogenesis of SC.

Purpose This study compared the effect of superior and inferior joint space injections of hyaluronic acid (HA) and evaluated osteoarthritic changes in patients diagnosed with temporomandibular joint (TMJ) anterior disc displacement without reduction (ADDw/oR) in association with osteoarthritis (OA) by cone-beam computed tomography (CBCT). Materials and Methods One hundred forty-one patients with research diagnostic criteria for ADDw/oR in association with TMJ OA were randomly assigned to 1 of 2 study groups that received superior or inferior joint space injection of HA. CBCT and clinical examination were performed before treatment and at 3 and 9 months after treatment. Results One hundred twenty-six patients returned for the 3-month evaluations, and 74 returned for the 9-month evaluations. Condylar remodeling and TMJ function showed improvement in most patients after treatment. At 3 months, remodeling scores in the superior and inferior groups were 2.14 ± 3.16 and 4.08 ± 3.82, respectively, and scores were 4.80 ± 3.36 and 7.47 ± 3.90 at 9 months. There were significant differences between the superior and inferior groups at 3 and 9 months after treatment (3-month, P = .002; 9-month, P = .002). The Helkimo index of the inferior group was significantly lower than that of superior group at 3 and 9 months (3-month, P = .008; 9-month, P = .028). There were no significant differences in maximal mouth opening between the 2 groups at 3 and 9 months (3-month, P = .82; 9-month, P = .20). Conclusion Superior and inferior joint space injections of HA are effective methods for the treatment of ADDw/oR in association with TMJ OA. The injection of HA within the inferior joint space appears to result in better condylar reparative remodeling and improvement in jaw function.

Background Synovial chondromatosis (SC) of temporomandibular joint (TMJ) is a rare proliferative disorder characterized by the formation of cartilaginous or osteocartilaginous nodules in synovium and joint space. Fibroblast growth factor 2 (FGF-2) is frequently applied in chondrogenic differentiation assays. Therefore, we hypothesized that FGF-2 might involved in the pathogenesis of SC. Methods SC synovium and loose bodies (LBs) specimens were observed by histological and immunohistochemical methods. Real-time PCR was conducted for comparing genes expressions in SC and normal synovium. SC synoviocytes were stimulated by FGF-2 in the presence or absence of its antagonist long pentraxin-3 (PTX3) for 6 days. Real-time PCR and alkaline phosphatase (ALP) activity were performed to examine the effects exerted by FGF-2 and PTX3. Results SC synovium, no matter facing the articular cavity or covering LB, was characterized by increased quantity of synoviocytes and blood vessels. FGF-2 was expressed in chondrocytes and fibroblast-like cells of LBs, and the wall of blood vessels. Expressions of chondrogenic genes (Sox9 and Wnt-4), osteogenic genes (Foxc2), FGF-2, and VEGF-A mRNA were significantly higher in SC synovium than that of the control group. The stimulation of FGF-2 on SC synoviocytes increased ALP activity and expressions of chondrogenic genes (Sox9, Col2α1, and Aggrecan), osteogenic genes (Foxc2, osteocalcin, and Col1α1), and VEGF-A, but PTX3 inhibited these effects. Conclusion FGF-2 was responsible for the formation of cartilaginous loose bodies and involved in the pathogenesis of SC.

Dental injuries are common following facial trauma. This article presents a rare injury: the dislocation of a third molar into the maxillary sinus after complex mandibular and maxillary tuberosity fractures. The possible mechanism and clinical treatment are discussed.

Summary Objective The etiology of Condylar hyperplasia (CH) of human temporomandibular joint (TMJ) remains largely unknown. Our previous study has demonstrated that enriched insulin-like growth factor-1(IGF-1) was expressed in the proliferation and hypertrophic layers of CH cartilage. Accordingly, this study was aimed to investigate whether IGF-1 regulates CH chondrocytes proliferation in condylar cartilage overgrowth and explore the molecular mechanism of IGF-1 involved in. Methods Chondrocytes were isolated from 6 CH and 3 normal cartilage (NC) specimens and cultured in alginate beads or monolayer, treated with IGF-1 or specific inhibitors such as 7-[trans-3-[(azetidin-1-yl)methyl]cyclobutyl]-5-(3-benzyloxyphenyl)-7H-pyrrolo[2,3-d]pyrimidin-4-amine (NVP-AEW541), U0126, and LY294002. Thereafter, cellular proliferation capacity was evaluated by Cell Viability Analyzer (alginate beads culture) or 3-(4,5-dimethylthiazo(-2-yl)-2,5-diphenyltetrazolium bromide (MTT) (monolayer culture). Gene expression levels of IGF-1, IGF-1 receptor (IGF-1R), collagen type II, type X and those genes associated with proliferation were evaluated by realtime PCR. Protein levels of IGF-1 and IGF-1R synthesized by CH chondrocytes were accessed by enzyme-linked immunosorbent assay (ELISA) and western blotting. Results CH chondrocytes enhanced cellular proliferation capacity and expressed significantly higher levels of messenger RNA (mRNA) and protein expressions of IGF-1 and IGF-1R, as compared with NC chondrocytes. Furthermore, enriched IGF-1 enhanced CH chondrocytes proliferation, up-regulated the expressions of specific genes associated with cellular proliferation and elevated the gene expression of collagen type II A1 ( COL2A1 ). Besides, IGF-1-mediated CH chondrocytes proliferation mainly depended on the mitogen-activated protein kinase (MAPK)–ERK pathway. Conclusions IGF-1 promotes human TMJ cartilage overgrowth in the developing process of CH by enhancing chondrocytes proliferation via MAPK–ERK pathway.

This study was designed to evaluate the feasibility and safety of screw-based semi-rigid intermaxillary fixation (IMF) combined with a specially designed occlusal splint in the conservative treatment of paediatric mandibular condylar fractures. Thirteen paediatric patients with 20 sides of condylar fractures treated with semi-rigid IMF were analyzed retrospectively. Semi-rigid IMF was achieved by inserting self-drilling IMF screws into the anterior alveolar bone of the maxilla and mandible suspended with elastic bands. An occlusal splint with a molar fulcrum was used for functional repositioning of the condylar fragment. After 4 weeks, the screws and occlusal splint were removed. During a mean period of 28.6 months' follow-up, the patients' maximal mouth opening increased to a mean of 37.69 mm. Clinical and radiological examinations revealed satisfactory results in facial symmetry and condylar remodelling. No clinical symptoms or radiographic evidence showed dental injuries associated with screw insertion. This study suggests that this method might be a safe, easy, and effective management of paediatric condylar fractures.