Open reduction and internal fixation of mandibular condylar fractures: A national inpatient sample analysis, 2005-2014.

The purpose of this study was to compare outcomes of open reduction and internal fixation (ORIF) versus closed reduction (CR) for mandibular condylar fractures.Patients included in the National Inpatient Sample (NIS) database (2005-2014) who were admitted to the hospital for unilateral mandibular condylar fracture were included in the analysis. Patient characteristics and clinical outcomes were compared between those who received ORIF and those receiving CR. Logistic regression analysis was performed to estimate odds ratios (ORs) for each aspect of the main observed events.NIS data of 12,303 patients who underwent ORIF and 4310 patients who underwent CR were analyzed. Compared to CR, ORIF had an increased risk of longer hospital stay (adjusted OR [aOR] = 1.78, 95% confidence intervals [CIs] = 1.51-2.09), higher total medical cost (aOR = 2.57, 95% CI = 2.17-3.05), and hematoma development (aOR = 10.66, 95% CI = 1.43-75.59), but had a lower risk of having wound complications (aOR = 0.86, 95% CI = 0.79-0.93).Patients with mandibular condylar fractures who receive ORIF have greater risk of having an extended hospital stay, higher total medical costs, and hematoma development but lower risk of experiencing wound complications compared to those who receive CR.

Synovial fluid­derived synovial fragments represent an improved source of synovial mesenchymal stem cells in the temporomandibular joint.

Surgery-obtained synovium specimens (SSSs) can provide a source of synovial mesenchymal stem cells (SMSCs) for experimental studies. However, these specimens contain diverse tissues, including the intima and subintima; therefore, these SMSCs are not entirely derived from the intima and their cell source is heterogeneous. The present study isolated synovial fragments (SFs) from synovial fluid dilutions extracted from patients with temporomandibular joint (TMJ) osteoarthrosis. Unlike SSSs, SFs, which are membranous and translucent, consist of only several cell layers, indicating the presence of only the intima. In the present study, SF cells (SFCs) and SSS cells (SSSCs) exhibited a homogeneous, fibroblast­like, spindle­shaped morphology after passaging in vitro. Furthermore, both cell types exhibited similar proliferative and differentiation potentials in vitro. However, SFCs exhibited more uniform surface markers compared with SSSCs when analysed by flow cytometry. Taken together, these results indicated that SFs contained a greater amount of unmixed intima than SSSs, and that SFCs exhibited more homogeneous characteristics than SSSCs, thereby offering an improved source of SMSCs in the TMJ.

Mesenchymal Stem Cells Obtained from Synovial Fluid Mesenchymal Stem Cell-Derived Induced Pluripotent Stem Cells on a Matrigel Coating Exhibited Enhanced Proliferation and Differentiation Potential.

Induced pluripotent stem cell-derived mesenchymal stem cells (iPSC-MSCs) serve as a promising source for cell-based therapies in regenerative medicine. However, optimal methods for transforming iPSCs into MSCs and the characteristics of iPSC-MSCs obtained from different methods remain poorly understood. In this study, we developed a one-step method for obtaining iPSC-MSCs (CD146+STRO-1+ MSCs) from human synovial fluid MSC-derived induced iPSCs (SFMSC-iPSCs). CD146-STRO-1-SFMSCs were reprogrammed into iPSCs by transduction with lentivirus-mediated Sox2, Oct-3/4, klf4, and c-Myc. SFMSC-iPSCs were maintained with mTeSR1 medium in Matrigel-coated culture plates. Single dissociated cells were obtained by digesting the SFMSC-iPSCs with trypsin. The dissociated cells were then plated into Matrigel-coated culture plate with alpha minimum essential medium supplemented with 10% fetal bovine serum, 1× Glutamax, and the ROCK inhibitor Y-27632. Cells were then passaged in standard cell culture plates with alpha minimum essential medium supplemented with 10% fetal bovine serum and 1× Glutamax. After passaging in vitro, the cells showed a homogenous spindle-shape similar to their ancestor cells (SFMSCs), but with more robust proliferative activity. Flow cytometric analysis revealed typical MSC surface markers, including expression of CD73, CD90, CD105, and CD44 and lack of CD45, CD34, CD11b, CD19, and HLA-DR. However, these cells were positive for CD146 and stro-1, which the ancestor cells were not. Moreover, the cells could also be induced to differentiate in osteogenic, chondrogenic, and adipogenic lineages in vitro. The differentiation potential was improved compared with the ancestor cells in vitro. The cells were not found to exhibit oncogenicity in vivo. Therefore, the method presented herein facilitated the generation of STRO-1+CD146+ MSCs from SFMSC-iPSCs exhibiting enhanced proliferation and differentiation potential.

Synovium fragment-derived cells exhibit characteristics similar to those of dissociated multipotent cells in synovial fluid of the temporomandibular joint.

Multipotent mesenchymal stem cells (MSCs) found in the synovial fluid (SFMSCs) of the tempromandibular joint (TMJ) remain poorly understood. During TMJ arthrocentesis, we discovered that synovial fluid collected from some patients with TMJ disorders contained not only SFMSCs but also synovium fragments (SFs). In this study, we attempted to characterize both the SFMSCs and SF-derived cells (SFCs) in order to further understand the role of MSCs in the synovial fluid of the TMJ. The SFs were membranous and translucent and consisted of several cell layers, indicating that their origin was only from the intima. SFCs were obtained by digestion of the SFs and subsequently expanded in vitro. SFMSCs were enriched by centrifugation of the synovial fluid and expanded in vitro. SFCs and SFMSCs displayed a similar fibroblast-like, spindle-shaped morphology, and we observed that some SFMSCs grew out of small tissue masses in culture. Flow cytometric analysis showed that both groups of cells expressed similar surface markers, including CD90, CD44, CD105, and CD73. However, both were negative for Stro-1, CD146, CD45, CD34, CD11b, CD19, and HLA-DR. Immunofluorescent staining showed that both SFs and SFMSCs expressed vascular cell adhesion molecule 1. Both SFCs and SFMSCs could be induced to differentiate down osteogenic, chondrogenic, adipogenic, and neurogenic lineages in vitro. Together, our results indicate that the intima is the most likely tissue origin of SFMSCs in the TMJ. Moreover, the SFs are composed of only intima and thus offer an improved source of synovium-derived MSCs compared to synovium specimens obtained by surgery, which contain both intima and subintima.

Therapeutic outcomes in the treatment of unilateral glenoid fossa fractures using intermaxillary elastic traction.

INTRODUCTION: This study aimed to evaluate the therapeutic outcomes of intermaxillary elastic traction in the treatment of unilateral glenoid fossa fractures. METHODS: Five patients with traumatic unilateral glenoid fossa fractures were treated with intermaxillary elastic traction at the Sun Yat-Sen University Hospital of Stomatology during a 5-year period from 2006 to 2011. Pantomography and Schüller position radiographs were obtained at days 7, 28, and 90 to monitor glenoid fossa fracture healing. Removal of the intermaxillary elastic traction and the arch bar splint occurred at day 90, and the patients were advised to initiate mouth-opening exercises. RESULTS: Schüller position radiographs revealed a 100% reduction rate of the glenoid fossa fracture for all patients; morphologies of the glenoid fossa and mandibular condyle were normal. Follow-up ranged from 6 months to 2 years. The occlusal relationship (degree of mouth opening) was excellent in all cases. Patient recoveries were uneventful; no complications occurred such as pain, snapping, or limitations of mouth opening. Average mouth opening was measured at 3.6 cm at the last follow-up. CONCLUSIONS: Intermaxillary elastic traction is an effective, simple, and feasible method in the treatment of a glenoid fossa fracture. Accurate reduction and stable fixation may be achieved without significant complications.

Multilineage differentiation of human bone marrow mesenchymal stem cells in vitro and in vivo.

The aim of the present study was to investigate the ability of human bone marrow-derived mesenchymal stem cells (BMSCs) to undergo multilineage differentiation. Human BMSCs were isolated from the ilia of donors by density gradient centrifugation, then purified by adherent separation and cultured in vitro. P3 or P4 BMSC populations were collected and induced for multilineage differentiation into osteoblasts, adipocytes and neuroblasts using an inductive medium in vitro. The BMSCs were cultured in either an osteoblast or chondroblast induction medium, seeded onto porous coral scaffolds and implanted into mice in vivo. The mice were sacrificed by anesthesia overdose at 6 or 9 weeks post-surgery. The scaffolds were then removed for analysis. Lipid vacuoles were observed subsequent to being cultured in an adipogenic medium. These accumulated lipid vacuoles were detected using Sudan Black B and Oil Red O (positive) staining. Deposited calcium was detected using von Kossa and Alizarin Red S (positive) staining subsequent to being cultured in an osteogenic medium. The BMSCs retracted to form neuron-like cells with axon- and dendrite-like processes following induction by ß-mercaptoethanol. The cells were positively stained by toluidine blue and glial fibrillary acidic protein (GFAP) immunohistochemistry. Newly formed bone tissues were observed and islands of cartilage tissue were also formed at 9 weeks post-implantation in vivo. The present study demonstrated that human BMSCs were homogeneous and differentiated with high fidelity to osteogenic, adipogenic, neurogenic or chondrogenic lineages. These cells also form bone and cartilage tissues when implanted in vivo and may therefore be used as seed cells in bone tissue engineering.

Computational synovial dynamics of a normal temporomandibular joint during jaw opening.

BACKGROUND/PURPOSE: Synovial fluid in the temporomandibular joint (TMJ) acts as a lubricant and shock absorber, facilitating smooth jaw movements by reducing friction and cushioning the articular cartilage and other tissues in the TMJ. This study investigated the flow pattern of synovial fluid in the articular cavity during jaw opening. METHODS: The upper TMJ compartment in a healthy individual was studied by computed tomography arthrography, and the intra-articular pressures were measured during jaw opening. The compartment was reconstructed in three dimensions, and finite volume fluid dynamic modeling was used to analyze the pattern of fluid flow and pressure distribution during jaw movements. RESULTS: In a closed-jaw position, the upper joint compartment assumed a dumbbell shape. During the jaw opening process, the anterior portion of the upper compartment decreased gradually until it disappeared completely when the jaw was opened. As the jaw opened, the posterior space enlarged gradually. During jaw opening, the pressure in the anterior space of the upper compartment was higher than that in the posterior space. The model indicated that synovial fluid circulated anticlockwise, forming local vortices in both anterior and posterior spaces. CONCLUSION: During jaw opening processes, the three dimensional configuration of a normal upper TMJ compartment changed as the joint disc moved, with the synovial fluid circulating in an anticlockwise direction and local vortices forming.

[New bone and cartilage tissues formed from human bone marrow mesenchymal stem cells derived from human condyle in vivo].

OBJECTIVE: To investigate the ability to form new bone and cartilage tissues of bone marrow mesenchymal stem cells (BMSC) derived from human condyle in vivo, to search the new source of seed cells in constructing tissue engineering condyle. METHODS: Bone marrow was collected from the irrigation solution from resected human condyle, and was isolated by density gradient centrifugation and then purified by adherent separation and cultured in vitro. P3 or P4 BMSC populations were induced into osteoblasts and chondroblast under inductive medium in vitro and then seeded on porous coral scaffolds. The appearance and affinity of cells were investigated via scanning electron microscope. And then osteoblast or chondroblast/coral scaffolds composites were implanted into the dorsum of nude mice. The mice were sacrificed by anaesthesia overdose at six and nine weeks after surgery and the scaffolds were removed for analysis. RESULTS: Scanning electron microscope showed that BMSC were adhering to the surface of coral and having an overlapped growth or to contact each other as net and stride over the pores. The in vivo scaffold specimens maintained the initial shape of the coral scaffold. The new formed bone tissues were clearly evident and islands of cartilage tissues were also found at nine weeks after implantation. CONCLUSIONS: These BMSC derived from human condyle possess the ability of forming bone and cartilage tissues when being implanted in vivo, and can be used as a kind of seed cells in constructing tissue engineering condyle.

Basic fibroblast growth factor enhances osteogenic and chondrogenic differentiation of human bone marrow mesenchymal stem cells in coral scaffold constructs.

Temporomandibular joint (TMJ) disorders are commonly occurring degenerative joint diseases that require surgical replacement of the mandibular condyle in severe cases. Transplantation of tissue-engineered mandibular condyle constructs may solve some of the current surgical limitations to TMJ repair. We evaluated the feasibility of mandibular condyle constructs engineered from human bone marrow-derived mesenchymal cells (BMSCs). Specifically, human BMSCs were transfected with basic FGF (bFGF) gene-encoding plasmids and induced to differentiate into osteoblasts and chondroblasts. The cells were seeded onto mandibular condyle-shaped porous coral scaffolds and evaluated for osteogenic/chondrogenic differentiation, cell proliferation, collagen deposition and tissue vascularization. Transfected human BMSCs expressed bFGF and were highly proliferative. Osteogenesis was irregular, showing neovascularization around new bone tissue. There was no evidence of bilayered osteochondral tissue present in normal articulating surfaces. Collagen deposition, characteristic of bone and cartilage, was observed. Subcutaneous transplantation of seeded coral/hydrogel hyaluran constructs into nude mice resulted in bone formation and collagen type I and type II deposition. Neovascularization was observed around newly formed bone tissue; bFGF expression was detected in implanted constructs seeded with bFGF expressing hBMSCs. This report demonstrates that engineered porous coral constructs using bFGF gene-transfected human BMSCs may be a feasible option for surgical transplantation in TMJ repair.

Bilateral coronoid hyperplasia (Jacob disease on right and elongation on left): report of a case and literature review.

A case is reported of bilateral coronoid hyperplasia. The literature is reviewed concerning this condition's etiology, pathogenesis, clinical characteristics, diagnosis, and treatment. Jacob disease and coronoid elongation are both clinical features of coronoid hyperplasia. It is usually accompanied by restricted opening. The etiology and pathogenesis of coronoid hyperplasia are unclear. The condition can be diagnosed by panoramic radiographs and with 3-dimensional reconstructions from computerized tomography image data sets. Hyperplasia of the coronoid processes can be treated using an intraoral approach for coronoidectomy and dynamic laser physiotherapy after surgery. Although hyperplasia of the coronoid processes is uncommon in clinic, it can be found through careful examination and proper radiographic study. A 39-year-old female patient was referred for coronoid hyperplasia (Jacob disease on right and elongation on left). The histologic diagnosis for the right condylar condition was osteochondroma.

[Measurement and analysis of the intra-articular pressure in temporomandibular joint with sudden-onset, severe closed lock].

OBJECTIVE: The study aims to find out the fluctuating curve of the intra-articular pressure in temporomandibular joint with sudden-onset, persistent, severe closed lock and discuss the mechanism of its formation. We also investigate the effects of the arthrocentesis. METHODS: 20 affected sides in 16 patients were collected. A No. 8 syringe needle was used to pierce into the upper compartment of TMJ. The pre-arthrocentesis intra-articular pressure was measured by the pressure transducer via the flexural rigid tubing at open and close bite. The curve and mean value were documented during the operation. RESULTS: The patients with sudden-onset, persistent, severe closed lock had significantly low negative intra-articular pressure in their affected temporomandible joints. The average pressures was (-9.947 +/- 8.854) kPa at open bite and (-6.475 +/- 4.147) kPa at close bite. CONCLUSION: The TMJs with sudden-onset, persistene, severe closed lock has particular characters on etiology and clinical behavior. Arthrocentesis is one of the effective treatments to the diseases.

[Maxilla reconstruction with the free iliac osteomuscular flap and simultaneous osseointegrated implant embeding].

OBJECTIVE: To evaluate the clinical outcome of reconstruction of maxillary defects with vascularized iliac crest flap and simultaneous osseointegrated implant embedding. METHODS: During September to October 2003, two patients with maxillary defects from tumor resection underwent microsurgical reconstruction. The free iliac osteomuscular flap transferring and simultaneous osseointegrated implant embedding were performed to repair the defects. Three months after the reconstructive surgery, an abutment operation was preformed and denture was applied in both cases. RESULTS: The flaps survived well. Postoperative follow-up for 8 to 9 months showed that the patients obtained good zygomaxillary appearance, normal occlusion, and satisfactory pronunciation, without oronasal fistula or other serious complications. CONCLUSIONS: The free iliac crest osteomuscular flap with simultaneous osseointegrated implant embedding is an ideal, effective and cosmetically acceptable method for maxilla reconstruction.