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Neurosensory disturbance is the most common consequence of sagittal split osteotomy (SSO). The purpose of this study is to quantitatively assess neurosensory deficiency and recovery to the preoperative status when the inferior alveolar nerve (IAN) was exposed versus unexposed during SSO.This is a single-center, prospective, cohort study of all patients undergoing bilateral SSO between August 2018 and July 2019. Patients were included in the study sample if they underwent bilateral SSO with an intact intraoperative IAN and were received follow-up assessment for at least a year. The predictor variable was the intraoperative IAN status (exposed vs unexposed). The outcomes of interest were the rate and timing of recovery to the preoperative status. The covariates were age, sex, and the magnitude and direction of surgical movements. Neurosensory function was quantitatively evaluated using the Semmes-Weinstein monofilament test at follow-up intervals of 1, 3, 6, and 12 months. Descriptive statistics, bivariate statistics, Cox proportional hazards regression, and Kaplan-Meier analyses were performed. P value.05 was considered statistically significant.Of 90 patients, 86 patients who underwent 172 SSOs were included in this study. The mean age was 22.95 ± 3.34 years (range, 17 to 30), 65 were women, and the range of surgical movements was 3 to 8.3 mm of advancement and 2 to 12 mm of setback. Eighty-five nerves (49.4%) were allocated to the unexposed group, and 87 (50.6%) to the exposed group, with statistically significant differences in the rate and timing of recovery (hazard ratio = 2.368; 95% confidence interval, 1.662 to 3.376; P .001). Among those with recovered nerves, the median time to recovery was 90 days in the unexposed group and 364 days in the exposed group (P .0001).IAN exposure during SSO is associated with an increased risk of neurosensory deficiency and an increased time of sensory recovery to the baseline threshold in patients aged 17 to 30 years. When the IAN remained fully enclosed in the canal of the distal segment, only 11% of patients had a measurable sensory deficit 1 year after surgery. In those patients with any degree of IAN exposure, 36% had a residual sensory deficit 1 year after surgery.

This study aimed to find out the correlation between different anatomical parameters of the mandible and the occurrence of a bad split in patients who had undergone bilateral split sagittal ramus osteotomy (BSSRO).At both the distal roots of the first molar (1) and the retromolar area (2), we measured the distance from the buccal margin of the inferior dental canal (IDC) to the buccal margin of the cortical bone (MCBC), the thickness of both buccal cortical (WBCB) and cancellous bone (WBCA), distance from the superior border of IDC to the alveolar crest (MCAC), buccolingual thickness (BLT), and thickness of cancellous bone (WCA). At the ramus, the distances between the sigmoid notch to the upper part of the lingula (SL) and the inferior border of the mandible (SIBM), the thickness of the ramus at the level of the lingula (BLTR), and the anteroposterior width of the ramus (APWR) were measured. The paired and independent t-tests were used when applicable, and a P-value 0.05 was considered significant.MCBC1 showed a significant difference between bad and non-bad split sides (P = 0.037). Both WBCA1 and WBCA2 show the same significant difference (P = 0.023, 0.024). Similarly, WCA1 and WCA2 showed a statistical difference between the bad and non-bad split sides (P = 0.027, 0.036). There were no statistically significant differences between the compared sides of WBCB1, WBCB2, MCAC1, MCAC2, SIBM, APWR, SL, and BLTR.Narrow space between IDC and the buccal cortical margin, along with the decrease in the thickness of both buccal cancellous bone and total cancellous bone at the inferior border of the mandible along the course of SSRO, has been implicated in the occurrence of bad split intraoperatively.

Printed cutting and repositioning templates could bring superior accuracy when transferring a maxillary plan to the operating room compared to a wafer-based method. However, the effect of these methods in different types of cases is inconclusive. The objective of the study was to compare the accuracy when using printed occlusal splints versus templates in simple and complicated cases.A retrospective cohort study design was used. Complicated cases were defined as cases involving impaction movement of more than 2 mm, occlusal plane canting of more than 3°, or midline discrepancies of more than 2.5 mm. Other cases were simple cases. Enrolled patients were randomly allocated into the digital occlusal splint (DOS) cohort and the digital templates (DT) cohort. The outcome variable was surgical accuracy, defined as the average deviation between the planned and postsurgical locations of bilateral maxillary central incisors, canines, first premolars, and first molars. Predictor variables were 1) operative complexity, simple versus complicated; and 2) technique for positioning the maxilla, DOS versus DT. Covariates were age and planned surgical movement. Two-way analysis of variance was used.Seventy patients were included in this study. Thirty-three were in the DOS cohort, and 37 in the DT cohort. The average deviation was significantly smaller in the complicated cases in the DT cohort (1.37 mm; 95% confidence interval, 1.08-1.66 mm) than that in the DOS cohort (2.47 mm; 95% confidence interval, 1.92-3.02 mm) (P = .002). The deviations in anteroposterior direction of complicated cases in the DT cohort were smaller than the corresponding values of the DOS cohort (P = .035). There is no significant difference between the deviation values of simple and complicated cases using templates (P = .116).These results indicate that in complicated cases, printed guiding templates exhibit better accuracy for repositioning the maxilla than printed occlusal splints, and the effect of templates in different cases proved to be stable.

Cartilage Decellularized ExtraCellular Matrix (dECM) materials have shown promising cartilage regeneration capacity due to their chondrogenic bioactivity. However, the limited retention of ECM components and the reduced integrity of functional ECM molecules during traditional decellularization processes impair the biomimicry of these materials. The current study aims to fabricate biomimetic materials containing decellularized cartilage particles that have an intact molecular structure and native composition as biomaterial inks and hydrogels for cartilage repair. For this, we established a novel two-fraction decellularization strategy for the preparation of reconstituted dECM (rdECM) particles by mixing the two-fraction components, as well as a one-fraction decellularization strategy for the preparation of biomimetic dECM (bdECM) particles. Hyaluronic acid-tyramine (THA) hydrogels containing rdECM or bdECM particles were produced and characterized via rheological test, swelling and stability evaluation, and compression test. The results showed that our novel decellularization strategies preserved intact proteoglycans and collagen at a higher retention rate with adequate DNA removal compared to traditional methods of decellularization. The addition of rdECM or bdECM particles significantly increased the shear moduli of the THA bioinks while preserving their shear-thinning properties. bdECM particle-embedded THA hydrogels also achieved long-term stability with a swelling ratio of 70% and high retention of glycosaminoglycans and collagen after long-term incubation, while rdECM particle-embedded THA hydrogels showed unsatisfactory stability as self-standing biomaterials. Compared to pure THA hydrogels, the addition of bdECM particles significantly enhanced the compression moduli. In summary, our decellularization methods are successful in the retention of functional and intact cartilage components with high yield. Both rdECM and bdECM particles can be supplemented in THA bioinks for biomimetic cartilage 3D printing. Hydrogels with cartilage bdECM particles possess the functional structure and the natural composition of cartilage ECM, long-term stability, and enhanced mechanical properties, and are promising biomaterials for cartilage repair., Journal of Materials Science and Technology, 160

Unfavorable fractures in sagittal split ramus osteotomy are hard to manage. The aim of this study is to develop a new classification method for unfavorable fractures of the proximal segment to guide clinical managements. After reviewing 964 cases of sagittal split ramus osteotomy, we found that the unfavorable fractures can be divided into 3 types: mandibular ramus transverse fractures (Type 1), bad fractures accompanied by free fragments (Type 2), and unexpected separation patterns without free fragments (Type 3). We calculated the incidence of each fracture type and provided instructions for their corresponding treatments. Thirty-six patients suffered from unfavorable fractures (7.4% of patients), among which 32 patients had unilateral fractures and 4 patients had bilateral fractures. There were 2 Type 1 fractures (0.2% of split sites), 8 Type 2 fractures (0.8% of split sites), and twenty-six Type 3 fractures (2.3% of split sites). Type 1 unfavorable fractures are difficult to deal with, but Types 2 and 3 are generally manageable and they have no significant impact on the final outcomes. The new classification can effectively guide treatment strategies for unfavorable fractures. Severe cases of unfavorable fractures are rare, and most unfavorable fracture cases have a positive prognosis if correctly treated in time.

The aim of this study was to classify the clinical feasibility and outcomes of open reduction treatment of old condylar head fractures (CHFs). This was a retrospective case series study of patients with old CHFs that were treated with open reduction and internal fixation, with anatomic reduction and sutured fixation of the articular disc. Preoperative and postoperative examinations were recorded and analyzed, including temporomandibular joint (TMJ) symptoms, occlusion, maximum interincisal opening (MIO), and mandibular deviation. Computed tomography (CT) was used to assess condylar morphology and position. Eleven patients with old CHFs were included (nine unilateral and two bilateral). The mean period from condylar fracture to operation was 8.9 months (ranging from 6 to 14 months). The mean follow-up period after surgery was 16.1 months (ranging from 12 to 22 months). At the end of follow-up period, no malocclusion was found, and the MIO had expanded considerably to 37.4 ± 3.8 mm. Postoperative CT showed that all fragments were properly reduced and the condyles were in the normal position. All patients showed apparently improved TMJ function, occlusion, and facial appearance. Our results showed that open reduction treatment could be an effective method for the treatment of old CHFs.

Osteochondroma is a common benign skeletal disorder for which different molecular and histological features of long bones have been reported. We investigated cell-of-origin and molecular mechanisms of a rare condylar osteochondroma (CO).Human fibrocartilage stem cells (hFCSCs) isolated from CO and normal condyle tissue were used for RNA sequencing, real-time PCR, Western Blotting, immunohistology, flowcytometry, as well as for chondrogenic differentiation, proliferation, and apoptosis detection assays.HFCSCs were fewer in number with weaker proliferative capacity and higher apoptosis ratio in the CO group. During the chondrogenic inducing process, hFCSCs from CO were prone to form more mature and hypertrophic cartilage. The result of RNA sequencing of hFCSCs from CO and normal condyle revealed a correlation between the PI3K/AKT signalling pathway and CO. Activated PI3K/AKT signalling might lead to functional changes in hFCSCs by enhancing cell apoptosis in the developmental process of CO. Increased expression of BCL2-like protein 11 (BIM) in CO tissue also supports this conclusion. Furthermore, the activation of the PI3K/AKT pathway in TMJ of mice induced histological disorder and increased apoptosis in condylar cartilage.We conclude that the activation of PI3K/AKT signalling in hFCSCs of CO suggests a new hypothesis for the cell-of-origin of human CO and another possible target to treat it.

Zhan Su,* Jie Zhang,* Peijie Tan, Songsong Zhu,* Nan Jiang* State Key Laboratory of Oral Diseases, National Clinical Research Center for Oral Diseases, Department of Oral & Maxillofacial Surgery, West China Hospital of Stomatology, Sichuan University, Chengdu, 610041, People’s Republic of China*These authors contributed equally to this workCorrespondence: Songsong Zhu; Nan Jiang, Email zss_1977@163.com; dent_jn@163.comIntroduction: Polyetheretherketone (PEEK) has good biosafety and chemical stability for bone repair. However, PEEK is biologically inert and cannot promote bone apposition. This study investigated whether graphene-modified PEEK (G-PEEK) could improve cell adhesion and osteogenic differentiation.Methods: G-PEEK was prepared by melted blending and was characterized. In vitro, the biocompatibility of G-PPEK and the ability to promote cell adhesion and osteogenic differentiation in rabbit bone marrow mesenchymal stem cells (rBMSCs) were examined using live and dead cell double staining, the cell counting kit-8 (CCK-8) assay, immunofluorescence and quantitative real-time PCR (qRT‒PCR). An in vivo rabbit extra-articular graft-to-bone healing model was established. At 4 and 12 weeks after surgery, CT analysis and histological evaluation were performed.Results: In vitro, G-PEEK significantly improved the adhesion and proliferation of rBMSCs, with good biocompatibility. In vivo, G-PEEK promoted new bone formation at the site of the bone defect.Conclusion: G-PEEK showed excellent osteogenesis performance, which promises new applications in implant materials.Keywords: polyetheretherketone, graphene, nanocomposites, cell adhesion, osteogenic differentiation

The pathological mechanism of temporomandibular joint osteoarthritis (TMJOA) is still unclear. Animal models induced by surgical interventions are one of the most ideal tools to imitate human pathological conditions. This review aims to define the similarities and differences of different surgical animal models.Articles of TMJOA surgical animal models were collected including anterior disc displacement, disc perforation, and discectomy. We analyzed their experiments strategies based on comparing preoperative selection, intraoperative methodology, and postoperative manifestations.No matter which surgical intervention is selected, abnormal stress forces the whole joint to remodel its structure so that it could adapt to functional requirements, resulting in TMJOA eventually. However, anterior disc displacement needs more than 16 weeks to obtain typical manifestations, where the methodology is complicated. The course of perforation and discectomy is around 12-16 weeks, but they could cause excessive damage to the TMJ structure.All surgical interventions can cause TMJOA, but the extent of pathology varies from each other. This review will assist future experiments to better understand the pathogenesis of TMJOA and choose the most appropriate model.

This study aims to show our institute’s experience in the treatment of HH and its associated facial deformities in adults and growing adolescents and to investigate condylar remodeling and volumetric changes and long-term stability of orthognathic surgery in adults. The study included consecutive patients with clinical and radiological features of HH who underwent high condylectomy with or without simultaneous orthognathic surgery from 2013 to 2018. The clinical outcomes were assessed based on functional activities, TMJ pain, and recurrence. Postoperative 3D condylar remodeling and orthognathic stability were evaluated with the use of ITK-Snap and 3D Slicer. Thirteen patients (8 females and 5 males) with a mean age of 26.3 ± 5.79 years (range; 13–34 years) were included with facial asymmetry as the chief complaint. The patients were followed up for a minimum of 12 months and a maximum of 4 years (mean; 16.85 ± 10.04). There were no postoperative complications, and all patients achieved a satisfactory functional and aesthetic outcome using a one-stage surgical procedure. There was no incidence of recurrence or further asymmetries, with long-term stability at the selected points showing a mean difference of less than ±1 mm. The affected condylar volume was significantly reduced following high condylectomy, with mean changes between T1 and T2 of −144. 80 mm3 (p = .012). However, the contralateral condylar volume remained stable, with a mean change of 2.54 mm3 (p = .881). One-stage high condylectomy and orthognathic surgery is a viable measure for the treatment of HH and associated deformities in adults. High condylectomy in early adolescence could result in termination of the disease, and aesthetic improvement with further constant orthodontist-surgeon follow-up is required.

Summary Objective This study was aimed to identify the residence of human fibrocartilage stem cells (hFCSCs), characterize their stem cell properties and investigate the functional mechanisms which regulate fibrocartilage stem cells (FCSCs) toward chondrogenic differentiation during cartilage homeostasis and repairing. Methods Cytological characteristics of hFCSCs and human orofacial mesenchymal stem cells (hOFMSCs) were analyzed. Chondrogenic potential of hFCSCs was compared with hOFMSCs both in vitro and in vivo. Regulatory role of SOX9 during FCSCs chondrogenesis was studied by shRNA interference in vitro, and by GFP+ FCSCs treatment in rat condylar cartilage defect model. SOX9 expression was also examined in temporomandibular joint osteoarthritis (TMJOA) patients’ cartilage surface. Results hFCSCs exhibited typical mesenchymal stem cell characteristics, with significantly stronger chondrogenic capability compared to hOFMSCs. Moreover, hFCSCs showed remarkably increased expression of SOX9. During cartilage pellet culture, there was stronger SOX9 expression in hFCSCs than hOFMSCs . SOX9 shRNA interference downregulated chondrogenic capability of hFCSCs in vitro, as well as disrupting migration and chondrogenic differentiation of GFP+ FCSCs toward mature chondrocytes in rat condylar cartilage defect. Of note, SOX9 expression was also found suppressed in the condylar superficial zone of TMJOA patients. Conclusion We found the existence of FCSCs in human TMJ cartilage, and characterized their distinct stem cell features. SOX9 is essential for hFCSCs chondrogenic differentiation, and a comprehensive understanding of the regulatory role of SOX9 in hFCSCs would be important for exploring potential intervention strategy of condylar cartilage degradation during TMJ disorders.

Bioinspired by the morphology of osteoclast-resorbed bone surfaces, we prepared a calcium-doped titanium phosphate (Ca-TiP) coating, which consists of a nanofibrous network, on titanium (Ti) substrate via a simple two-step hydrothermal method, trying to mimic natural bone compositionally and microstructurally. The in vitro studies show that the Ca-TiP coating with synergistic features of nanofibrous biomimetic topography and surface chemistry could elicit intensively osteogenic behavior and responses including enhanced cell adhesion, spreading, and proliferation as well as alkaline phosphatase (ALP) activity and up-regulated expression of bone-related genes, which inevitably benefit the formation of new bone and the quality of osseointegration. When the two control groups are compared in vivo, the significantly improved new bone formation in the early stage and the much stronger interfacial bonding with the surrounding bone for Ca-TiP coating suggest that Ca-TiP coating modified Ti implants hold great potential for orthopedic and dental applications.

Chlorpyrifos (CPF) is an extensively used organophosphorus pesticide. Recently, it has attracted increasing attention due to environmental health problems caused by it. Although numerous studies have discovered the dechlorinated photoproduct of CPF, its structure and toxicity remain largely unknown. In this study, we systematically investigated the structure and toxicity of dechlorinated photoproduct of CPF. The CPF degradation experiment was performed, and its products were identified by ultra high performance liquid chromatography-orbitrap fusion tribid mass spectrometer (UHPLC-Orbitrap Fusion TMS). Additionally, bond dissociation energy (BDE) calculations and photoproduct chemical synthesis were employed to determine the structure of dechlorinated photoproduct of CPF. The toxicity of CPF photoproduct was evaluated through the Ecological Structure Activity Relationships (ECOSAR) Class Program, the Toxicity Estimation Software Tool (T.E.S.T.) software, and acute toxicity testing. The results indicated that the dechlorinated photoproduct of CPF was identified as O,O-Diethyl-O-(3,5-dichloro-2-pyridyl) phosphorothioate (Dechloro-CPF), which was produced in large quantity within the first 30 min of photodegradation experiment. The acute and chronic toxicity values of Dechloro-CPF were obviously higher than those for the other two photoproducts. The median lethal dose (LD

This study aims to investigate motivations, ways of gaining information, and concerns for orthognathic surgery of patients with skeletal dentomaxillofacial deformities before receiving the treatment, and to explore directions for improvement in doctor-patient communications in the clinical practice.Presurgical patients were asked to fill out a questionnaire about their basic information, the approaches via which they knew about the surgery, as well as their motivations and concerns for the surgery.One hundred ninety two questionnaires were included in the analysis in total. Patients (females: males = 2.69:1) with an average age of 23.79 ± 4.36 mainly regarded facial esthetics (103, 53.65%) as a primary concern. Although about 80.20% of patients accessed medical information through the Internet, it was still an irreplaceable way to know through consulting specialists.The majority of patients were young, unmarried women without a stable income. For most patients, the primary motivation to receive the surgery was an improvement in facial esthetics and the biggest concern was the operation effect. Access to medical information through the Internet has become very important access to medical knowledge.

Although artificial polymeric scaffolds act as vital characters in bone repair, their application is limited due to their inferior bioactivity. Herein, osteoinductive poly(ε-caprolactone) (PCL) composite scaffolds were prepared by synchronously enlisting bioactive nanohydroxyapatite (nHA), bioglass (BG), and bone morphogenetic protein-2 (BMP-2), which was bound up with polydopamine (pDA). It was found that pDA deposition not only significantly enhanced hydrophilicity and cell affinity of composite scaffolds but also endowed steady immobilization of BMP-2 with long-term yet sustained release. Compared to pure PCL and PCL/nHA/BG (PHB) scaffolds, the designed PHB-pDA-BMP-2 scaffolds significantly induced the differentiation of bone marrow stromal cells toward an osteogenic lineage. Meanwhile

An analytical method based on high performance liquid chromatography coupled with quadrupole time-of-flight mass spectrometry (HPLC-Q-TOF/MS) was established for the rapid screening and identification of 62 kinds of illegally added traditional Chinese medicine (TCM) in food. According to the notice of the Ministry of Health of the People's Republic of China on further regulating the management of raw materials of health food (Weifa Jianfa (2002) No. 51), the characteristic components of the 62 kinds of TCM were screened, and the corresponding characteristic component lists of different TCM were obtained. Methanolic extracts of the 62 kinds of standard medicinal materials were subjected to HPLC-Q-TOF-MS analysis. The filtrate was separated on a Thermo Accucore aQ column (150 mm×2.1 mm, 2.6 μm) using 0.1%(v/v) formic acid aqueous solution or water and acetonitrile as the mobile phases for gradient elution in the electrospray positive and negative ion scanning mode. All the data were determined on the full scan of primary mass spectrometry and secondary mass spectrometry, with mass acquisition ranges of 100-1000 Da and 50-1000 Da, respectively. A 10 mmol/L sodium formate solution was used as the mass correction solution in both the positive and negative ion modes. Library View software was used to establish the precursor ion accurate quality database and the product ion fragment mass spectrometry database of the corresponding characteristic components of the different kinds of TCM. In the Library View database software, the name of each characteristic component of the 62 kinds of TCM was input (serial number) in order to classify the screened characteristic components. The samples were processed using the same method and analyzed. Peak View software was used to rapidly analyze and screen the target components of the TCM. The high-resolution data collected from the samples to be tested were imported into the Peak View software, followed by the compound list of the established MS database of standard medicinal materials. After setting the identification method parameters and library retrieval parameters, a matching analysis was performed, and the candidate substances for each peak were automatically identified by comparing the mass spectrum, accurate molecular ion mass number, fragment ion mass number, retention time, and other related parameters. The determination conditions of compound detection were as follows: the comprehensive score was more than 70 points. The molecular formula, retention time, mass spectrum as well as the primary isotope mass spectrometry, primary mass spectrometry, and secondary mass spectrometry data were matched with the library compounds. The corresponding list of "TCM-characteristic components" was established, and a high-resolution MS library of 388 characteristic components from the 62 types of TCM was constructed. Each TCM contains 5-10 characteristic components. According to the screening analysis of the actual food samples of the prepared wine, substitute tea, and beverage, one batch of the prepared wine sample matched with seven characteristic components of epimedium, and it was inferred that epimedium was added to the prepared wine samples. This method can allow for the qualitative screening of TCM without standards and has the characteristics of high throughput, accuracy, simplicity, and rapidity. It solves the difficulty in identifying and confirming illegally added TCM in food; provides technical methods and a basis for cracking down on the illegal addition of TCM in food; and facilitates the rapid screening and identification of illegally added TCM in food.

ObjectiveInvestigate functional roles of Igf1 in fibrocartilage stem cell (FCSC) for temporomandibular joint (TMJ) cartilage growth and homeostasis.MethodsGli1-CreER+; RosaTdTomato mice were used for validating FCSCs lineage labeling efficiency. In Gli1-/Col2-CreER+; Igf1fl/fl mice, TMJ cartilage morphological and functional changes were characterized at 4 weeks and 5 months after Igf1 deletion. H&E, Safranine O and immuno-histochemistry staining were performed. FCSCs specificity were characterized using EdU and TUNEL staining. A unilateral anterior crossbite (UAC) mouse model was generated for mimicking TMJ osteoarthritis status.ResultsIn Gli1-CreER+; RosaTdTomato mice, RFP labeled FCSCs showed favorable proliferative capacity. 4 weeks after Igf1 deletion, Gli1+ and Col2+ cell lineages led to distinct pathological changes of TMJ cartilage morphology. A more serious reduction of cartilage thickness and cell density were found in the superficial layers in Gli1-CreER+; Igf1fl/fl mice. 5 months after Igf1 deletion, more severe disordered cell arrangement in TMJ cartilage were found in both groups with Gli1+ and Col2+ specific deletion of Igf1. Immunostaining showed that PI3K/Akt signaling pathway was blocked in the superficial layers of TMJ in Gli1-CreER+; RosaTdTomato mice. Finally, deletion of Igf1 in FCSCs significantly aggravated osteoarthritis (OA) phenotypic changes in TMJ in UAC mice model, characterized in decreased cartilage thickness, cell numbers and loss of extracellular matrix secretion.ConclusionIgf1 deletion disrupted stem cell functions of FCSCs, leading to disordered cell distribution during TMJ growth, as well as exaggerated the OA process in TMJ under pathological condition. In TMJ cartilage, Igf1 expression in FCSCs is critical for PI3K/Akt activation, which may be involved in regulating FCSCs self-renewal and differentiation.

The aim of this study is to investigate the effect of bimaxillary orthognathic surgery on orofacial myofunctional changes in skeletal class III patients. 35 patients who received Le Fort I maxillary advancement osteotomy and mandibular SSRO setback were included in this study. Facial expression function was analyzed by "placid" or "smile" expressions using chL-chR, ∠chRnchL, and ls-li. Occlusal force and balance were analyzed using a T-scan III digital occlusal analysis system. Maximum mouth opening (MMO) was measured prior to surgery and 2/14/28/42/90/180/360 days after surgery. After surgery, patients recovered facial expressions in no less than 3 months for both the "placid" or "smile" facial expression. Patients obtained significantly improved 'smile' expressions 3 months after the operation compared to preoperative "smiles", and this improvement remained stable 12 months after the operation. Occlusal force was significantly decreased with the balance of occlusion lost immediately after surgery. These conditions gradually recovered, and patients finally obtained a more balanced and stronger occlusion [occlusion balance: 6.7 ± 2.7 mm vs. 4.1 ± 3.0 mm (day -7 vs. day 42); occlusion force: 19.6 ± 7.0 kg vs. 24.2 ± 9.3 kg (day -7 vs. day 180)]. However, patients had smaller postoperative mouth opening compared to preoperation opening during our follow-up. Our results confirmed that orthognathic surgery obstructs orofacial myofunctions of skeletal class III patients in the short-term. In the long-term, orthognathic surgery results in more stable and balanced orofacial myofunctions. By understanding the process of functional recovery of orofacial muscles after orthognathic surgery, we hope to accelerate patient's recovery from surgery.

To improve the performance of polyether ether ketone matrix (PEEK) in hard tissue repair and replacement applications, we fabricated graphene (G) reinforced PEEK with graded G concentrations (0.1%-5%) through injection molding. The mechanical properties, surface morphology, chemical composition and thermal stability of the composites have been characterized through universal mechanical testing, scanning electron microscopy, contact-angle measurement, transmission electron microscope, X-ray photoelectron spectroscopy, X-ray diffraction and thermal analysis system. The biocompatibility has been assessed in vitro and the bone repair function of the composite implant have been assessed in vivo using a rabbit mandibular bone defect model. Mechanical testing results suggest that the composite samples have compressive moduli similar to that of the natural bone. Although addition of G into PEEK does not significantly influence the composite tensile, flexural or compressive moduli, it can significantly enhance the ductility and toughness of the material. On the other hand, all G-reinforced PEEK implants demonstrated enhanced adhesion and differentiation of rat bone marrow stromal cells (BMSCs), with 5% G-PEEK showing the highest bioactivity among all samples. The in vivo osseointegration data further revealed that 5% G-PEEK has the best effect in promoting osseointegration and bone regeneration, in both early stage and late stage bone re-growth. Study shows that our G-reinforced PEEK-based implants provides a promising strategy for enhancing the performance of future regenerative bone implants.