A Three-branch Jointed Feature and Topology Decoder guided by game-theoretic interactions for temporomandibular joint segmentation.

Segmentation of the temporomandibular joint (TMJ) disc and condyle from magnetic resonance imaging (MRI) is a crucial task in TMJ internal derangement research. The automatic segmentation of the disc structure presents challenges due to its intricate and variable shapes, low contrast, and unclear boundaries. Existing TMJ segmentation methods often overlook spatial and channel information in features and neglect overall topological considerations, with few studies exploring the interaction between segmentation and topology preservation. To address these challenges, we propose a Three-Branch Jointed Feature and Topology Decoder (TFTD) for the segmentation of TMJ disc and condyle in MRI. This structure effectively preserves the topological information of the disc structure and enhances features. We introduce a cross-dimensional spatial and channel attention mechanism (SCIA) to enhance features. This mechanism captures spatial, channel, and cross-dimensional information of the decoded features, leading to improved segmentation performance. Moreover, we explore the interaction between topology preservation and segmentation from the perspective of game theory. Based on this interaction, we design the Joint Loss Function (JLF) to fully leverage the features of segmentation, topology preservation, and joint interaction branches. Results on the TMJ MRI dataset demonstrate the superior performance of our TFTD compared to existing methods.

Imaging evaluation of disc position and status after temporomandibular joint arthroscopic disc repositioning and suturing surgery.

Objective: This study aimed to explain the change of disc position at different over-corrected place after arthroscopic disc repositioning and suturing surgery. Study design: Patients treated with temporomandibular joint arthroscopic disc repositioning and suturing surgery were reviewed. All patients underwent magnetic resonance imaging (MRI) before, immediately after surgery and at 2-year follow-up. The position of disc was checked and the change was compared. Results: 133 patients were included in the final analysis with 203 TMJ sides. The incidence rate for anterior movement of the disc after surgery was 33.0 %. Disc repositioned between 12 and 1 o'clock showed smaller movement rate of 22.6 %, while higher movement rate of 53.6 % was seen when repositioned between 2 and 3 o'clock. Conclusions: After arthroscopic disc repositioning and suturing surgery for ADD patients, the repositioned disc showed tendency to move forward. 12 to 1 o'clock was optional disc site for repositioning while excessive over-correction was not recommended.

Synthesis, crystal and electronic structures, linear and nonlinear optical properties, and photocurrent response of oxyhalides CeHaVIO4 (Ha = Cl, Br; VI = Mo, W).

Four heteroanionic oxyhalides, CeClMoO4, CeBrMoO4, CeClWO4, and CeBrWO4, have been studied as multifunctional materials, which show a combination of good second harmonic generation (SHG) response and photocurrent signals. Millimeter-sized CeHaVIO4 (Ha = Cl, Br; VI = Mo, W) crystals were grown by halide salt flux. The crystal structure of CeHaVIO4 crystals was accurately determined by single-crystal X-ray diffraction. CeClMoO4, CeBrMoO4, and CeBrWO4 are isostructural to each other, and crystallize in the acentric LaBrMoO4 structure type. CeClWO4 crystallizes in a new structure type with unit cell parameters of a = 19.6059(2) Å, b = 5.89450(10) Å, c = 7.80090(10) Å, and ß = 101.4746(8)°. The bandgaps of CeHaVIO4 fall into the range of 2.8(1)-3.1(1) eV, which are much smaller than those of isotypic LaHaVIO4 (Ha = Cl, Br; VI = Mo, W) in the range of 3.9(1)-4.3(1) eV. The narrowing of bandgaps in CeHaVIO4 originates from the presence of partially filled 4f orbitals of cerium atoms, which was confirmed by density functional theory (DFT) calculations. The moderate bandgaps make CeHaVIO4 suitable for infrared nonlinear optical (IR NLO) applications. CeBrMoO4 and CeBrWO4 exhibit moderate SHG responses of 0.58× AGS and 0.46× AGS, respectively, and are both type-I phase-matching materials. Moderate SHG response, easy growth of crystals, high ambient stability, and type-I phase-matching behavior make CeBrMoO4 and CeBrWO4 great materials for IR NLO applications. CeHaVIO4 films also exhibited good photocurrent response upon light radiation. This work demonstrates the rich structural chemistry of the REHaVIO4 (RE = Y, La-Lu; Ha = Cl, Br; VI = Mo, W) family and the potential presence of more multifunctional materials.

Chitosan based macromolecular hydrogel loaded total glycosides of paeony enhances diabetic wound healing by regulating oxidative stress microenvironment.

Oxidative stress microenvironment caused by reactive oxygen species (ROS) accumulation seriously hinders wound healing in diabetes, which brings great burden to global health. Various wound dressings on the market focus on delivering active substances to promote wound healing in diabetes. However, the complex pathological microenvironment of diabetic wounds often leads to the inactivation of delivery factors, which often leads to treatment failure, and thus, emerging therapeutic approaches are urgently needed. In this study, a macromolecular hydrogel synthesized by crosslinking N-carboxyethyl chitosan, hyaluronic acid-aldehyde, and adipic acid dihydrazide, with self-healing and injectable abilities was used to deliver total glycosides of paeony (TGP). The TGP incorporated hydrogel could obviously induce fibroblasts proliferation and secretion of various extracellular matrix proteins and growth factors, induce migration and angiogenesis of vein endothelial cells, and enhance macrophages polarization to M2 phenotype by eliminating accumulated ROS. In diabetic wound models, the ROS-scavenging hydrogel efficiently enhanced proliferation, re-epithelialization, collagen deposition, as well as angiogenesis in the wound area. Besides, the dressing induced the macrophages polarization from M1 phenotype (pro-inflammatory) to M2 phenotype (anti-inflammatory) and decreased the levels of inflammatory cytokines, thereby enhancing the diabetic wound healing. The wounds treated with TGP incorporated hydrogel almost completely healed 16 days after treatment. However, the residual wound areas in the groups of Con, INTRA, and Gel are 55.2 ± 4.6 %, 33.7 ± 6.5 %, and 34.9 ± 6.1 % on the 16th day, respectively. This hydrogel with pathological microenvironment improvement ability affords a novel therapeutic strategy for enhancing healing of chronic diabetic wound.

3D-printed temporomandibular joint-mandible combined prosthesis: A prospective study.

OBJECTIVES: The study aimed to introduce and evaluate a new customized temporomandibular joint-mandible combined prosthesis with 3D printing fabrication. MATERIALS AND METHODS: This was a prospective study including patients with temporomandibular joint-mandible combined lesions. A 3D-printed customized temporomandibular joint-mandible combined prosthesis was implanted to repair the joint and jaw defect. Clinical follow-up and radiographic examinations were taken to assess the clinical efficacy. The assessment indices were compared by the Wilcoxon signed rank test. RESULTS: Eight patients were treated with the combined prosthesis and included in this study. All prostheses were accurately positioned and fixed without wound infection, prosthesis exposure, displacement, loosening, or fracture. All cases had no mass recurrence at the last follow-up point. Pain, diet, mandibular function, lateral mandibular movement to the diseased side, and maximal interincisal opening showed significant improvements at every follow-up point and went to a stable condition at 6 months after the operation. But the lateral movement to the non-operated side was still limited following surgery. CONCLUSION: The 3D-printed combined prosthesis may be an alternative to other well-established reconstructions for temporomandibular joint and mandible defects.

Introduction of temporomandibular joint and skull base combined reconstruction by autogenous bone graft.

OBJECTIVE: This study introduces the application of autogenous bone graft for the reconstruction of temporomandibular joint (TMJ) and skull base combined defects. MATERIALS AND METHODS: Patients treated with autogenous bone grafts for reconstruction of the TMJ and skull base were reviewed. All patients underwent virtual surgical design to confirm the osteotomies of the combined lesion and the selections of autogenous bone graft, fabrication of surgical templates to transfer the plan to actual operation, and reconstruction of autogenous bone graft for the TMJ and/or skull base. Surgical outcomes were assessed by clinical examinations and radiological data. RESULTS: Twenty-two patients were involved in this study. Ten patients underwent reconstruction of the skull base by a free iliac or temporal bone graft and preservation of the TMJ. Twelve patients underwent skull base reconstruction by the same methods and total reconstruction of the TMJ by half sternoclavicular joint flap or costochondral bone graft. No severe complications occurred after surgery. The occlusion relationship was stable and similar to that of the preoperative state. The pain and maximal interincisal opening were significantly improved by the 101.2-month follow-up. CONCLUSION: Autogenous bone graft is a good alternative for repairing the TMJ and the skull base structure and function. CLINICAL RELEVANCE: The study introduced the application of autogenous bone graft for the reconstruction of temporomandibular joint and skull base combined defect, which is a good way to repair the defect and restore the function.

Biomechanical evaluation of Chinese customized three-dimensional printed titanium miniplate in the Lefort I osteotomy: A finite element analysis.

Objectives: This work aims to evaluate the biomechanical behavior of Chinese customized three-dimensional (3D) -printed miniplates by means of finite element analysis (FEA). Methods: A 3D Lefort I osteotomy model was established by Mimics. Two models were established to compare the strain behaviors of customized miniplate and conventional L-shaped miniplate. Hypermesh and ABAQUS were used to establish computer-aided engineering finite element models. The stress distribution on the mini-plates, screws and bone and the relative displacement of the maxilla segments were analyzed by loading postoperative occlusal force. Results: The displacements for customized mini-plate fixation were notably smaller than L-shaped mini-plate fixation. The maximum stresses on the screws, mini-plates and cortical bone for customized mini-plates were smaller than that for L-shaped miniplates. Conclusion: Chinese customized 3D-printed miniplates provide better postoperative stability and offer a good alternative to the conventional L-shaped miniplate system.

Thermosensitive hydrogel loaded with concentrated growth factors promote bone repair in segmental bone defects.

Treating critical-size bone defects beyond the body's self-healing capacity is a challenging clinical task. In this study, we investigate the effect of concentrate growth factors (CGFs) loaded Poloxamer 407 hydrogel on the viability and osteogenic differentiation potential of bone marrow mesenchymal stem cells (BMSCs) and reconstruction of critical-size bone defects. In vitro, this CGFs-loaded thermosensitive hydrogel can significantly promote proliferation, maintain cell viability, and induce osteogenic differentiation of BMSCs by up-regulating the mineralization and alkaline phosphatase (ALP) activity, as well as gene markers, including runt-related transcription factor-2 (Runx-2), type I collagen (Col-1), osteocalcin (OCN), as well as osteopontin (OPN). In vivo, Micro-CT radiography analysis and histological detection demonstrated that the CGFs-loaded hydrogel significantly induced bone healing and reconstructed the medullary cavity structure in critical-size bone defect models. In conclusion, this strategy of transplantation of CGFs-loaded hydrogel promoted bone regeneration and prevented bone nonunion, so as to provide basis for clinical treatment for repairing critical-size bone defects.

Improved Muscle Regeneration into a Joint Prosthesis with Mechano-Growth Factor Loaded within Mesoporous Silica Combined with Carbon Nanotubes on a Porous Titanium Alloy.

Total joint replacement (TJR) is widely applied as a promising treatment for the reconstruction of serious joint diseases but is usually characterized by critical loss of skeletal muscle attachment to metal joint prostheses, resulting in fibrous scar tissue formation and subsequent motor dysfunction. Tissue engineering technology may provide a potential strategy for skeletal muscle regeneration into metal joint prostheses. Here, a porous titanium (Ti) alloy scaffold coated with carbon nanotubes (CNTs) and mesoporous silica nanoparticles (MSNs) through electrophoretic deposition (EPD) was designed as a mechano-growth factor (MGF) carrier. This two-layered coating exhibits a nanostructured topology, excellent MGF loading, and prolonged release performance via covalent bonding to improve myoblast adhesion, proliferation and myogenic differentiation in porous Ti alloy scaffolds without cytotoxicity. The Akt/mTOR signaling pathway plays a key role in this process. Furthermore, in vivo studies show that the scaffold promotes the growth of muscle, rather than fibrotic tissue, into the porous Ti alloy structure and improves muscle-derived mechanical properties, the migration of satellite cells, and possibly immunomodulation. In summary, this nanomaterial-coated scaffold provides a practical biomaterial platform to regenerate periprosthetic muscle tissue and restore comparable motor function to that of the natural joint.

Prognostic indicators of arthroscopic discopexy for management of temporomandibular joint closed lock.

In order to optimize patient selection for temporomandibular joint (TMJ) arthroscopic discopexy to achieve favorable outcomes, prognostic indicators impacting the results are important to analyze. This longitudinal retrospective study aimed to analyze various prognostic factors impacting surgical outcomes following arthroscopic discopexy for management of TMJ closed lock using success criteria based on pain, maximal interincisal opening, diet, and quality of life. Furthermore, a quantitative MRI assessment was performed pre- and post-operatively. Multivariate analysis was used to evaluate various prognostic variables including gender, age, side, duration of illness, Wilkes staging, parafunctional habits, splint therapy and orthodontic treatment. A total of 147 patients (201 joints) were included. The outcome was categorized as excellent (n = 154/76.61%), good (n = 34/16.91%), or poor (n = 13/6.46%) with a success rate of 93.54%. Patients aged > 30 years old (p = 0.048), longer duration of illness (12-24 months: p = 0.034) and (> 24 months: p = 0.022), and patients with Wilkes stage IV (p = 0.002) were all significantly more likely to be in the poor outcome group. Finally, orthodontic treatment showed a significant association with excellent outcomes (p = 0.015). Age, duration of illness, Wilkes staging, and orthodontic treatment are considered significant prognostic factors that can predict the outcomes following the arthroscopic discopexy for management of TMJ closed lock.

Computational Mechanistic Study of Brønsted Acid-Catalyzed Unsymmetrical 1,2,4,5-Tetrazines Synthesis.

Density functional theory (DFT) calculations were conducted to gain insight into the reaction mechanism of the Brønsted acid-catalyzed unsymmetrical 1,2,4,5-tetrazine synthesis. Various possible reaction pathways were considered, and the most favorable one can be characterized via sequential six steps, including addition of DCM to hydrazine 1 giving complex IM4, N-H bond activation in IM4 mediated by sulfur, AcOH-assisted substitution of 3 with sulfur-activated hydrazine 2, HNO2-assisted addition of nitrile to intermediate 8, cyclization, and intramolecular elimination leading to the final product 7. Among the six steps, sulfur activation of IM4 N-H bond is found to be the rate-determining step (RDS). The mechanism rationalizes the experimental observation that 2 equiv of sulfur leads to the best yield of product. Furthermore, we disclosed that the Brønsted acid additives (i.e., acetic acid and nitrous acid) served triple roles as catalyst, proton shuttle, and hydrogen bond donor and acceptor in the whole catalysis.

The magnetic resonance imaging evaluation of condylar new bone remodeling after Yang's TMJ arthroscopic surgery.

To evaluate the post-operative condylar bone remodeling after the treatment of Yang's arthroscopic surgery. Consecutive cases from Jan 2017 to May 2018 that received Yang's arthroscopic surgery were included in this study, the TMJ MRI examinations were performed preoperatively and postoperatively (follow up for 1 year or more), and condylar bone remodeling was estimated. A total of 229 patients (29 male and 200 female) were included in the study, 161 patients had new bone formation, and the average age was 17.5 ± 2.1a. There was no new bone formation in 68 patients with an average age of 24.5 ± 0.7a. The percentage of new bone formation patients in 10-15 years of age was 94.33% and decreases as the age increases. In the position of new bone formation, the posterior slope of condyle was the most (129 joints), the second was the top of condyle (54 joints), the third was around condyle (33 joints), only 25 joints had new bone on the anterior slope of condyle. After TMJ arthroscopic surgery, the condyle has the ability to form new bone, and the younger the age, the stronger the ability of new bone formation. The formation of new bone was most in posterior slope and least in anterior slope of condyle.

Experimental study on mandibular length and facial symmetry of low estrogen level and anterior disc displacement of temporomandibular joint.

This study was aimed at elucidating the changes of mandible symmetry in a rabbit model with low estrogen levels induced by ovariectomy (OVX) combined with temporomandibular joint (TMJ) anterior disc displacement without reduction (ADDWoR). 32 growing rabbits were randomly allocated into 4 groups; OVX group, ADDWoR group, OVX+ ADDWoR group and control group. In OVX and OVX+ ADDWoR groups, bilateral OVX was performed and then the serum level of 17ß-estradiol was evaluated every week. In ADDWoR group and OVX+ ADDWoR group, the right TMJ was surgically opened and the disc was displaced anteriorly and the left TMJ was also surgically opened and closed without any manipulation of the disc. All rabbits had CT scan before and at the end of the study and the mandible measurements were performed on the 3D-reconstructed model. The mandible in ADDWoR group was consistently shorter on the right side resulting in a midline shift to the ipsilateral side. While in OVX+ ADDWoR group, the mandibular length of the right side was more shorter than in ADDWoR group, moreover, mandibular deviation was therefore more severe. In OVX group, there was no difference regarding the length of mandible compared to the control group. There was no difference regarding the mandibular length between left and right sides in the control group.

Kaempferide Prevents Titanium Particle Induced Osteolysis by Suppressing JNK Activation during Osteoclast Formation.

Kaempferide (KF) is an O-methylated flavonol, a natural plant extract, which is often found in Kaempferia galanga. It has a variety of effects including anti-carcinogenic, anti-inflammatory, anti-oxidant, anti-bacterial and anti-viral properties. In this study, we aimed to investigate whether KF effectively inhibits titanium particle induced calvarial bone loss via down regulation of the JNK signaling pathway. In the mice with titanium particle induced calvarial osteolysis, the Low dose of KF mildly reduced the resorption pits while in the high dose group, fewer scattered pits were observed on the surface of calvarium. Histological examination showed fewer osteoclasts formation in the KF group. In mouse bone marrow macrophages (BMMs) and RAW264.7 cells, KF significantly inhibited the osteoclast formation and bone resorption at 12.5 µM. However, KF does not affect the mature osteoclast F-actin ring formation. But when being co-treated with KF and anisomycin, BMMs differentiated into mature osteoclasts. At the molecular levels, the JNK phosphorylation was inhibited and the osteoclastogenesis-related specific gene expression including V-ATPase d2, TRAP, calcitonin receptor (CTR), c-Fos and NFATc1 was markedly suppressed. In conclusion, these results indicated that KF is a promising agent in the treatment of osteoclast-related diseases.

Injecting vascular endothelial growth factor into the temporomandibular joint induces osteoarthritis in mice.

It is unclear whether vascular endothelial growth factor (VEGF) can initiate osteoarthritis (OA) in the temporomandibular joint (TMJ). In this study we evaluated the effects of intra-articular injection of exogenous VEGF in the TMJ in mice on the early stage. Forty-eight male Sprague-Dawley mice were equally divided into 3 groups. In the vegf group, the mice received an injection of VEGF solution (50 µL) in the TMJ once a week over a period of 4 weeks. In the sham group, the mice received an injection of saline (50 µL). The control group did not receive any injection. Four mice from each group were sacrificed at 1, 2, 4, and 8 weeks. Gradual prominent cartilage degeneration was observed in the vegf group. Additionally, this group showed higher expressions of metalloproteinase (MMP)-9, MMP-13, receptor activator of nuclear factor-kappa-B ligand (RANKL), and a higher number of apoptotic chondrocytes and VEGF receptor 2 (VEGFR2)-positive chondrocytes. Micro-computed tomography (CT) revealed prominent subchondral bone resorption in the vegf group, with a high number of osteoclasts in the subchondral bone. In vitro study demonstrated that VEGF can promote osteoclast differentiation. In conclusion, our study found that VEGF can initiate TMJ OA by destroying cartilage and subchondral bone.

Modified surgical techniques for total alloplastic temporomandibular joint replacement: One institution's experience.

OBJECTIVE: To present three modified techniques of total alloplastic temporomandibular joint replacement (TMJ TJR) and to evaluate the outcomes regarding prosthesis stability and heterotopic bone formation. MATERIAL AND METHODS: A total of 15 patients (19 joints), treated with the Biomet stock prosthesis from May 2006 to May 2013, were retrospectively analyzed. Surgical procedures were performed with the following three modifications: bone grafting of the glenoid fossa; salvage of TMJ discs; and harvesting of retro-mandibular subcutaneous fats. The glenoid fossa depth was measured preoperatively by Surgicase 5.0 software. All patients were evaluated by radiographic examination and surgical observation. RESULTS: The fossa was grafted with an autogenous bone in 15 joints (78.9%). In 4 joints (21.1%), only bone repair was performed. Radiographic evaluation revealed a good integration between the autogenous and host bones. All patients showed postoperative occlusal stability. In 5 joints (26.3%), the discs were salvaged. Both bleeding and operation time were reduced. Fat grafts were harvested in 17 joints (89.5%), in which there were no abnormalities in the periprosthetic bone structure. In 2 joints (10.5%), with no fat grafting, heterotopic bone formation was found. CONCLUSIONS: The modified techniques of TJR help to improve prostheses stability, reducing heterotopic bone formation and avoiding additional scars.