Amino acid-based supramolecular chiral hydrogels promote osteogenesis of human dental pulp stem cells via the MAPK pathway.

Critical-size defects (CSDs) of the craniofacial bones cause aesthetic and functional complications that seriously impact the quality of life. The transplantation of human dental pulp stem cells (hDPSCs) is a promising strategy for bone tissue engineering. Chirality is commonly observed in natural biomolecules, yet its effect on stem cell differentiation is seldom studied, and little is known about the underlying mechanism. In this study, supramolecular chiral hydrogels were constructed using L/d-phenylalanine (L/D-Phe) derivatives. The results of alkaline phosphatase expression analysis, alizarin red S assay, as well as quantitative real-time polymerase chain reaction and western blot analyses suggest that right-handed D-Phe hydrogel fibers significantly promoted osteogenic differentiation of hDPSCs. A rat model of calvarial defects was created to investigate the regulation of chiral nanofibers on the osteogenic differentiation of hDPSCs in vivo. The results of the animal experiment demonstrated that the D-Phe group exhibited greater and faster bone formation on hDPSCs. The results of RNA sequencing, vinculin immunofluorescence staining, a calcium fluorescence probe assay, and western blot analysis indicated that L-Phe significantly promoted adhesion of hDPSCs, while D-Phe nanofibers enhanced osteogenic differentiation of hDPSCs by facilitating calcium entry into cells and activate the MAPK pathway. These results of chirality-dependent osteogenic differentiation offer a novel therapeutic strategy for the treatment of CSDs by optimising the differentiation of hDPSCs into chiral nanofibers.

Association between bilateral condylar resorption and reduced volumes of the craniofacial skeleton and masticatory muscles in adult patients: A retrospective study.

Objectives: This retrospective cohort study aimed to analyze volumes of craniomaxillofacial bone and masticatory muscles of young adults with bilateral idiopathic condylar resorption. Methods: This was a retrospective cohort study of 84 adults with bilateral idiopathic condylar resorption (BCR) and 48 adults with normal temporal-mandibular joint (TMJ) matched for age and sex (mean age, 23.2 ± 3.6 years). The volumes of craniomaxillofacial bone and masticatory muscles, as well as intercondylar angle were measured. Unpaired t-tests and Pearson correlation tests were applied to analyze the data. Multivariable linear regression models were used to estimate the association between bilateral condylar volume and volumes of craniomaxillofacial bone and masticatory muscles adjusted for age, sex, and disc status. Results: Compared to the control group, the BCR group displayed significant decreased volumes of craniomaxillofacial bone (p < 0.001), craniomaxillofacial bone without mandible (p < 0.001), mandible (p < 0.001), mandible without mandibular condylar process (p < 0.001), bilateral masseter muscle (p < 0.001) and bilateral temporalis muscle (p < 0.001), as well as the intercondylar angle (p < 0.001). These variables were significantly correlated to the volume of mandibular condylar process (0.5< r < 0.8; p < 0.001). By linear regression analyses, significant associations were found for the bilateral condylar volume with craniomaxillofacial bone volume and mandible bone volume. Conclusions: Young adults with BCR displayed smaller volumes of craniomaxillofacial skeleton and masticatory muscles, and smaller intercondylar angle than the normal patients. The craniofacial musculoskeletal volume and intercondylar angle are associated with mandibular condylar process volume.

Feasibility of simultaneous TMJ arthroscopy in ADDwoR patients undergoing orthognathic surgery for jaw deformity.

This study evaluated the feasibility of simultaneous temporomandibular joint (TMJ) arthroscopy and orthognathic surgery as a new treatment strategy for anterior disc displacement without reduction (ADDwoR) patients with severe jaw deformities. Twelve ADDwoR patients with facial deformities who underwent arthroscopy and orthognathic surgery between September 2015 and December 2019 were retrospectively evaluated. Pre- and postoperative maximum incisal opening (MIO) and joint pain were recorded. Computed tomography (CT) and three-dimensional cephalometric analysis were performed at 3 (T1) and ≥6 (T2) months postoperatively. Magnetic resonance imaging (MRI) of the TMJ was performed before, ≤7 days after and ≥6 months after surgery. The lateral profile radiological findings, the symmetry of the maxilla and mandible, and the MRI measurements were compared. Anterior disc displacement did not recur, and the maximum incisal opening (MIO) increased from 27.4 mm to 32.7 mm after surgery (p < 0.05). No significant differences were found in the lateral profile, symmetry indices or condylar height via MRI between T1 and T2. Joint morphology and the position of both the maxilla and mandible remained stable during postoperative follow-up, while joint symptoms were markedly relieved and facial appearance was noticeably improved. Combined arthroscopy and orthognathic surgery is effective and recommended for ADDwoR patients with jaw deformities.

Long-term investigation of minimally invasive alcohol-based therapy as the treatment of odontogenic keratocyst:A retrospective cohort study.

The aim of this study was to evaluate the clinical efficacy of alcohol-based therapy for patients with large odontogenic keratocysts (OKCs). The study was implemented as a retrospective, single-center study. Patients treated with ethanol-based therapy for odontogenic keratocyst were retrospectively evaluated for baseline and postoperative data. The pre- and postoperative clinical situation and the extent of radiographic shrinkage were compared. The event is defined as the achievement of >50% reduction in cyst volume. The cyst reduction rate calculated on panoramic radiographs ranged from 7.4% to 99.9% (mean [standard deviation] 55.3% [27.9%]) and was statistically significant (P < 0.05). Specifically, it has been found that, radiographically, 47.6% of patients achieved >50% reduction in cyst volume within 12 months. The continuous cortical bone was rebuilt, and the cyst cavity was filled with regenerated trabecular bone. The 22 included patients presented with nonclinical problems, had no need for further intervention, and exhibited persistent impaction of the teeth. The results of this study demonstrated that ethanol-based therapy triggered marked radiographic reductions of large OKC, indicating that using this technique is efficient.

Shish-kebab structure fiber with nano and micro diameter regulate macrophage polarization for anti-inflammatory and bone differentiation.

Biopolymer grafts often have limited biocompatibility, triggering excessive inflammatory responses similar to foreign bodies. Macrophage phenotype shifts are pivotal in the inflammatory response and graft success. The effects of the morphology and physical attributes of the material itself on macrophage polarization should be the focus. In this study, we prepared electrospun fibers with diverse diameters and formed a shish-kebab (SK) structure on the material surface by solution-induced crystallization, forming electrospun fiber scaffolds with diverse pore sizes and roughness. In vitro cell culture experiments demonstrated that SK structure fibers could regulate macrophage differentiation toward M2 phenotype, and the results of in vitro simulation of in vivo tissue reconstruction by the microenvironment demonstrated that the paracrine role of M2 phenotype macrophages could promote bone marrow mesenchymal stem cells (BMSCs) to differentiate into osteoblasts. In rats implanted with a subcutaneous SK-structured fiber scaffold, the large-pore size and low-stiffness SK fiber scaffolds demonstrated superior immune performance, less macrophage aggregation, and easier differentiation to the anti-inflammatory M2 phenotype. Large pore sizes and low-stiffness SK fiber scaffolds guide the morphological design of biological scaffolds implanted in vivo, which is expected to be an effective strategy for reducing inflammation when applied to graft materials in clinical settings.

Fabrication of three-dimensional orthodontic force detecting brackets and preliminary clinical test for tooth movement simulation.

This study aimed to develop an ultraminiature pressure sensor array to measure the force exerted on teeth. Orthodontic force plays an important role in effective, rapid, and safe tooth movement. However, owing to the lack of an adequate tool to measure the orthodontic force in vivo, it remains challenging to determine the best orthodontic loading in clinical and basic research. In this study, a three-dimensional (3D) orthodontic force detection system based on piezoresistive absolute pressure sensors was designed. The 3D force sensing array was constructed using five pressure sensors on a single chip. The size of the sensor array was only 4.1 × 2.6 mm, which can be placed within the bracket base area. Based on the barometric calibration, conversion formulas for the output voltage and pressure of the five channels were constructed. Subsequently, a 3D linear mechanical simulation model of the voltage and stress distribution was established using 312 tests of the applied force in 13 operating modes. Finally, the output voltage was first converted to pressure and then to the resultant force. The 3D force-detection chip was then tested to verify the accuracy of force measurement on the teeth. Based on the test results, the average output force error was only 0.0025 N (0.7169%) (p = 0.958), and the average spatial positioning error was only 0.058 mm (p = 0.872) on the X-axis and 0.050 mm (p = 0.837) on the Y-axis. The simulation results were highly consistent with the actual force applied (intraclass correlation efficient (ICC): 0.997-1.000; p < 0.001). Furthermore, through in vivo measurements and a finite element analysis, the movement trends generated when the measured orthodontic forces that acted on the teeth were simulated. The results revealed that the device can accurately measure the orthodontic force, representing the first clinical test of an orthodontic-force monitoring system. Our study provides a hardware basis for clinical research on efficient, safe, and optimal orthodontic forces, and has considerable potential for application in monitoring the biomechanics of tooth movement.

Efficacy of Arthroscopic Discopexy on Condylar Growth in Temporomandibular Joint Anterior Disc Displacement: A Randomized Clinical Trial.

BACKGROUND: Adolescents with temporomandibular joint (TMJ) anterior disc displacement (ADD) frequently develop dentofacial deformities. It is unknown if adjunctive arthroscopic discopexy compared to orthodontic treatment alone increases condylar growth and then improves dentofacial deformity. This study aimed to determine whether arthroscopic discopexy before functional appliance (joint-occlusal treatment) or single functional appliance (occlusal treatment) increases condylar growth and improves dentofacial deformity among adolescents with TMJ ADD. METHODS: A multicenter, randomized, parallel controlled trial was conducted in three centers in China. Adolescents diagnosed with TMJ ADD and dentofacial deformity were enrolled. Eligible participants were randomly assigned to a joint-occlusal group or occlusal group at a ratio of 2:1. MRI, cephalometric radiographs were evaluated at baseline, 8 months and 14 months. The primary outcome was changes in condylar height from 14 months to baseline. Secondary outcomes were changes in skeletal position. RESULTS: A total of 240 patients (14.65±1.88 years of age) were randomized (joint-occlusal group: 160; occlusal group: 80). The overall difference in condylar height between groups was 3.65 mm (95% CI, 3.10 to 4.19; p < 0.001). The between-group differences in condylar height on the left and right sides were 3.60 mm (95% CI, 2.92 to 4.28; p < 0.001) and 3.69 mm (95% CI, 3.06 to 4.32; p < 0.001), respectively. Significant between-group differences were noted in skeletal position (all p < 0.001). CONCLUSIONS: Joint-occlusal treatment can promote condylar growth and improve dentofacial deformity in adolescents after 14 months when compared with single occlusal treatment.

The Retrospective Study of Magnetic Resonance Imaging Signal Intensity Ratio in the Quantitative Diagnosis of Temporomandibular Condylar Resorption in Young Female Patients.

According to the literature, there is no reliable and quantitative method available for the diagnosis and prognosis of early or potential temporomandibular joint (TMJ) condylar resorption (CR) thus far. The purpose of this study was to raise a new noninvasive method to quantitatively evaluate condylar quality using the signal intensity ratio (SIR) on magnetic resonance imaging (MRI) in order to assist in the diagnosis of TMJ CR. A retrospective exploratory study was performed to compare the condyle-to-cerebral cortex signal intensity ratios (SIR) on MRI among young female patients. We included 60 patients, and they were divided into three groups: the bilateral normal TMJ group (group 1), the bilateral TMJ anterior disc displacement (ADD) but without CR group (group 2), and the bilateral TMJ anterior disc displacement (ADD) with CR group (group 3). The SIR difference between the three groups was analyzed by the Kruskal-Wallis test (K-W test). The sensitivity, specificity, accuracy, and area under curve (AUC) were calculated by the receiver operating characteristic (ROC) curves. There was high consistency between the surgeon and the radiologist in the evaluation of the magnetic signal intensity with intraclass correlation coefficients of 0.939-0.999. The average SIR was 1.07 in the bilateral normal TMJ group (group 1), 1.03 in the ADD without CR group (group 2), and 0.78 in the ADD with CR group (group 3). It could be found by the K-W test that group 3 was significantly different from group 1 and group 2 (p < 0.05), while there was no significant difference between group 1 and group 2. The optimal critical SIR value was 0.96 for the diagnosis of CR according to the ROC curves and Youden index (p < 0.001, AUC = 0.9). The condyle-to-cerebral cortex SIR can be used as a noninvasive diagnostic tool for the quantitative evaluation of condylar quality and diagnosis and prognosis of CR. SIR ≥ 0.96 indicates a healthy condyle, while SIR < 0.96 is considered the optimal critical value for the diagnosis of CR. These findings are important for personalized and accurate treatment and prognosis prediction.

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.

Periodontal Inflammation-Triggered by Periodontal Ligament Stem Cell Pyroptosis Exacerbates Periodontitis.

Periodontitis is an immune inflammatory disease that leads to progressive destruction of bone and connective tissue, accompanied by the dysfunction and even loss of periodontal ligament stem cells (PDLSCs). Pyroptosis mediated by gasdermin-D (GSDMD) participates in the pathogenesis of inflammatory diseases. However, whether pyroptosis mediates PDLSC loss, and inflammation triggered by pyroptosis is involved in the pathological progression of periodontitis remain unclear. Here, we found that PDLSCs suffered GSDMD-dependent pyroptosis to release interleukin-1ß (IL-1ß) during human periodontitis. Importantly, the increased IL-1ß level in gingival crevicular fluid was significantly correlated with periodontitis severity. The caspase-4/GSDMD-mediated pyroptosis caused by periodontal bacteria and cytoplasmic lipopolysaccharide (LPS) dominantly contributed to PDLSC loss. By releasing IL-1ß into the tissue microenvironment, pyroptotic PDLSCs inhibited osteoblastogenesis and promoted osteoclastogenesis, which exacerbated the pathological damage of periodontitis. Pharmacological inhibition of caspase-4 or IL-1ß antibody blockade in a rat periodontitis model lead to the significantly reduced loss of alveolar bone and periodontal ligament damage. Furthermore, Gsdmd deficiency alleviated periodontal inflammation and bone loss in mouse experimental periodontitis. These findings indicate that GSDMD-driven PDLSC pyroptosis and loss plays a pivotal role in the pathogenesis of periodontitis by increasing IL-1ß release, enhancing inflammation, and promoting osteoclastogenesis.

Do simultaneous mandibular advancement and temporomandibular joint prosthesis impact the upper airway in TMJ ankylosis patients?

BACKGROUND: Ankylosis of the temporomandibular joint (TMJ) is a pathological disorder which results in patients' limited or even complete failure of mouth opening. When TMJ ankylosis occurs during the growing age, moderate to severe micrognathia might be the proposed scenario of such cases, accompanied by obstructive sleep apnea and hypopnea syndrome (OSAHS). TMJ reconstruction using total TMJ prostheses with mandibular advancement (MA) can simultaneously improve the function and aesthetic profile of such patients. The purpose of this study was to determine whether the upper airway can be improved after TMJ reconstruction with total TMJ prostheses combined with or without MA in TMJ ankylosis patients. METHODS: Fourteen patients with pre-(T1) and post-(T2) operative CT scans were included. Patients were divided into two groups according to the operation with or without MA (MA/WoMA). The changes of the upper airway and jaw bones were comparatively analyzed within and between the two groups. RESULTS: In MA Group, the volume of the total upper airway (Vt) and palatopharynx (V1), together with the surface area (SA) of the total upper airway (SAt) and palatopharynx (SA1) increased significantly after the operation by 41.4%, 43.2%, 36.3% and 36.6%, respectively. In WoMA Group, V1, SAt and SA1 increased significantly by 21.0%, 19.0% and 23.1% following surgery. The changes of Point B (P<0.01), Y-axis angle (P<0.01), SNB (P<0.01), and ANB (P<0.01) were significantly greater in MA Group than in WoMA Group. Comparing both groups, the maxilla, and mandible were more backward in MA Group than in WoMA group before the operation, but there was no significant difference of the final position of the maxilla and mandible after the operation between both groups. CONCLUSIONS: Release of TMJ ankylosis and condylar reconstruction using total joint prostheses simultaneously with MA could significantly improve the total volume and other various parameters of the upper airway, while, only the dimension of the palatopharynx increased in cases without MA.

The effect of arthroscopic disc repositioning on facial growth in juvenile patients with unilateral anterior disc displacement.

OBJECTIVE: To investigate the effect of arthroscopic disc repositioning on condylar development and mandibular asymmetry in juvenile patients with unilateral temporomandibular joint (TMJ) anterior disc displacement (ADD). PATIENTS AND METHODS: A retrospective cohort study was conducted on unilateral juvenile anterior disc displacement (UJADD) patients of 10-20 years of age treated in Shanghai Ninth People's Hospital from 2010 to 2017. The primary predictor was TMJ arthroscopic disc repositioning surgery, according to which patients were divided into a surgery group and a control group. Initial and re-examined (with at least 6-month interval) magnetic resonance imaging (MRI) and posteroanterior cephalometric radiographs (PA) were collected. The condylar heights on both sides of the TMJ were measured by MRI and the difference between them was calculated. Menton (Me) deviation was measured based on PA. Changes in condylar height difference and Me deviation were compared between the two groups. RESULTS: A total of 108 UJADD patients were collected in this study, including 55 patients in the surgery group and 53 patients in the control group. There were no significant differences in age, sex and follow-up time between the two groups. The condylar height difference was (-0.61 ± 2.02) mm in surgery group and (1.68 ± 1.73) mm in control group (P < 0.0001); while the Me deviation was (-1.00 ± 1.15) mm in surgery group and (1.81 ± 1.96) mm in control group (P < 0.0001), indicating that TMJ arthroscopic disc repositioning surgery could significantly improve condylar height difference and Me deviation. CONCLUSIONS: UJADD should be treated as early as possible, especially in juvenile patients, in order to improve condylar development and avoid jaw deformities.

Functional orthodontics after arthroscopic disk repositioning in adolescent anterior disk displacement with mandibular retrusion.

OBJECTIVE: Condylar remodeling is crucial in retrognathic adolescents with anterior disk displacement without reduction (ADDwoR). This study aimed to evaluate the efficacy of functional orthodontics after arthroscopic disk repositioning surgery in improving condylar remodeling. STUDY DESIGN: A retrospective cohort study was performed to evaluate the condylar remodeling in patients with retrognathic unilateral ADDwoR who received arthroscopic disk repositioning surgery from March 2013 to December 2017. The primary predictor variable was functional orthodontics, based on which patients were divided into group A and group B. The outcome variables were condylar remodeling on both the affected side and the unaffected side measured by using the 3-circle method. The independent-sample t test was performed to test the difference between the 2 groups. A P value less than 0.05 was considered significant. RESULTS: In total, 117 patients (28 males and 109 females) were included in our study, with 75 cases in group A (follow-up: 7.48 months) and 62 cases in group B (follow-up: 7.95 months). Group A showed better condylar remodeling on the affected side compared with group B, but there was no significant difference on the unaffected side. CONCLUSIONS: Functional orthodontics after arthroscopic disk positioning leads to improved condylar remodeling in patients under 17 years of age with ADDwoR and mandibular retrusion.

Measurement of Mandibular Condylar Height Based on Magnetic Resonance Imaging.

The aim of this study was to find out the most appropriate method of measuring condylar height on temporomandibular joint (TMJ) magnetic resonance imaging (MRI). Traditional three-circle method, modified three-circle method and ramal plane (RP) method were used by 2 separate observers for the measurement of condylar height and long axis of condyle on TMJ MRI. Pearson correlation coefficient (PCCs), intra-class correlation coefficient (ICC), paired t test and Bland-Altman analysis were applied for the comparison of CH and long axis of condyle between 2 observers. Thirty-two patients' images were finally included in our study. Comparing the 3 methods, it was revealed that the RP method has the highest consistency among the observers, followed by the modified three-circle method, and the traditional three-circle method has the worst consistency. The RP method is preferred for measuring the condylar height on MRI. If mandible edge cannot be observed on MRI, the modified three-circle method is recommended.

Stability of Orthognathic Surgery in the Treatment of Condylar Osteochondroma Combined With Jaw Deformity by CT Measurements.

PURPOSE: We evaluated the stability of orthognathic surgery in the treatment of unilateral condylar osteochondroma combined with jaw deformity. PATIENTS AND METHODS: Patients with unilateral condylar osteochondroma and jaw deviation deformity who had undergone surgery at the Ninth People's Hospital of Shanghai Jiaotong University School of Medicine from July 2014 to March 2017 were enrolled. The operation included a low condylectomy and both Le Fort I osteotomy and bilateral mandibular sagittal split osteotomies. ProPlan CMF, version 1.4, software (Materialise, Leuven, Belgium) was used to reconstruct and measure the preoperative, immediately postoperative, and follow-up (>6 months) maxillofacial computed tomography images. The position of the jaw and contralateral condyle and remodeling of the affected side were compared during follow-up. RESULTS: Eight patients were included in the present study. The canting of the maxilla was significantly decreased postoperatively, and the contralateral condyle had rotated inward. The position of the maxillary and contralateral condyles was stable during follow-up, and the posterior aspect of the affected condyle demonstrated significant resorption. CONCLUSIONS: The results of single-stage surgery combined with orthognathic surgery and condylar osteochondroma resection were stable, and the affected condyle stump had adaptively reconstructed.

Assessment of Occlusal Appliance for the Reposition of Temporomandibular Joint Anterior Disc Displacement With Reduction.

The aim of our study was to evaluate the success rates and prognoses of patients treated with occlusal appliances used to reposition the temporomandibular joint anterior disc displacement with reduction (ADDWR). A sample of 144 consecutive patients (210 joints) diagnosed with ADDWR based on MRI were included in our study. Disc recapture was confirmed in a mandible-anterior position to eliminate joint clicking based on magnetic resonance imaging (MRI). Anterior repositioning appliance (ARS) was applied to keep the mandible in this position. The occlusal surface of the ARS was ground down by 1 mm approximately every 4 weeks for bite reconstruction. MRI was carried out before treatment, 6 months after the start of treatment, at the end of the treatment, and at their last follow-up visit. A Cox regression model was used to estimate the risk of failure of the treatment. The mean treatment duration was 9.5±2.6 months. A total of 177 joints (84.3%) were successfully repositioned at the end of splint treatment according to MRI. Regular follow-up indicated that almost 53% of the patients had normal disc-condyle relationships after 2 years. Sex, age, treatment duration, and orthodontics used were included in the final Cox regression model, with hazard ratios of 1.375, 1.141, 0.396, and 0.364, respectively. ARS is inferior for recapturing ADDWR in the long-term. It is thus better to explore other more effective methods to reposition the displaced disc in patients with ADDWR.

Yang's Classification of Juvenile TMJ Anterior Disc Displacement Contributing to Treatment protocols.

This study aims to establish a new staging system of temporomandibular joint (TMJ) anterior disc displacement (ADD) and evaluate its role in guiding the treatment plan. A consecutive sample of 522 juvenile patients (780 joints) diagnosed as ADD based on magnetic resonance imaging (MRI) was included and analyzed. 674 joints received TMJ treatments according to our staging system, while 106 joints rejected any treatment; only for follow-up. The outcomes were judged according to our success criteria. The prognosis of our staging system was also evaluated in comparison to Wilkes classification. Kaplan-Meier survival analysis showed that significant stratifications of the ameliorative rate were found at all subgroups within any two stages in our staging system, except for subgroups between stages 0 and 1, stages 2 and 3, and stages 3 and 4. After analyzing the interactions between different candidate prognostic factors in a Cox model, the relative risks of deterioration of ADD included treatment methods (HR = 42.94, P < 0.0001), disease course (HR = 0.98, P = 0.0019), stages of ADD (HR = 3.81, 9.62, 12.14, P = 0.016, 0.000,0.000 respectively for stage 2, stage 3 and stage 4) and the interaction between ADD stages and treatment methods. The C index of this model was 0.87. The new staging system of TMJ ADD appears reliable, and benefits to making treatment planning and predicting the prognosis.

Can anterior repositioning splint effectively treat temporomandibular joint disc displacement?

The aim of this study was to determine whether anterior repositioning splint (ARS) can effectively treat temporomandibular joint (TMJ) anterior disc displacement with reduction (DDwR) in juvenile Class II patients. This study investigated disc repositioning clinically and through use of MRI with 12-month follow up. Patients with skeletal Class II malocclusions and DDwR diagnosed by magnetic resonance imaging (MRI) were treated with ARS. The efficacy of ARS was assessed clinically and by means of MRI before treatment (T0), immediately after bite registration (T1), at the end of treatment (T2), and at 12 months after functional appliance treatment (T3). Improvement in TMJ pain, TMJ noises, and range of mandibular movement were assessed. MRI evaluation was based on disc-condylar relationship in parasagittal images. Seventy-two juvenile patients with 91 joints were included in this study. The average age was 15.7 years old (range, 10-20 years) at first visit. There were statistically significant reductions in TMJ pain, disability in daily life and TMJ clicking (P < 0.01). MRI at T2 indicated that the success rate was 92.31% (84/91), but decreased to 72.53% (66/91) at T3. The unsuccessful splint disc capture was mainly observed in late adolescence, especially over 18 years old. Using MRI results as the gold standard, we found that clinical assessment had an accuracy rate of 75.82% at 12-month follow-up. In conclusion, although success rate for ARS treatment decreased over time, both clinical findings and MRI examination indicate that the ARS is relatively effective in repositioning the DDwR, especially for patients in early puberty. However, further and larger studies are needed to evaluate the outcome with ARS.

The Effect Evaluation of Functional Appliance Used for Class II Patients With Temporomandibular Joint Anterior Disc Displacement.

Orthopedic functional appliances are usually used to correct patients with retrognathic mandible. However, a part of cases have a trend of relapse after splint treatment. The aim of this study was to explore the role of temporomandibular joint disc position in functional appliance treatment. This study included 8 patients who had 1 joint anterior disc displacement with reduction (ADDWR) and the other joint anterior disc displacement without reduction (ADDWoR) confirmed by magnetic resonance imaging (MRI). Only the ADDWR joint could return to its normal position after wearing the anterior repositioning appliances (ARAs). Condylar morphology, condylar height, and disc length were evaluated 6 months after ARA treatment. The MRI showed that new bone appeared on 7 joints with ADDWR and on 1 joint with ADDWoR. The condylar height has increased 1.4 mm in the ADDWR group, while 0.1 mm shorter in the ADDWoR group. Disc length has increased from 8.5 to 8.7 mm in the ADDWR group and 0.4 mm shorter in the ADDWoR group after wearing the ARA. Our results suggested that it is noneffective of functional appliance used for class II malocclusion adolescents with ADDWoR and only a normal disc-condyle relationship benefits condyle growth by functional appliance. Thus it is important to reposition the disc as soon as possible.

A new modified bone grafting technique for periodontally accelerated osteogenic orthodontics.

The aim of this study was to introduce an improved surgical technique using a pouch design and tension-free wound closure for periodontally accelerated osteogenic orthodontics (PAOO) in the anterior alveolar region of the mandible.Patients with bone dehiscence and fenestrations on the buccal surfaces of the anterior mandible region underwent the modified PAOO technique (using a pouch design and tension-free closure). Postoperative symptoms were evaluated at 1 and 2 weeks intervals following the procedure. Probing depth (PD), gingival recession depth (GRD), and clinical attachment level (CAL) were assessed at the gingival recession sites at baseline, postoperative 6 and 12 months. Cone-beam computerized tomography (CBCT) was used for quantitative radiographic analyses at baseline, 1 week and 12 months after bone-augmentation procedure.The sample was composed of a total of 12 patients (2 males and 10 females; mean age, 21.9 years) with 72 teeth showing dehiscence/fenestrations and 17 sites presenting with gingival recessions. Clinical evaluations revealed a statistically significant reduction in swelling, pain, and clinical appearance from postoperative week 1 to week 2 (P < .05). Moreover, gingival recession sites exhibited a significant reduction in the GRD and an increase in CAL after surgery with mean root coverage of 69.8% at the end of observation period (P < .01). Both alveolar bone height and width increased after surgery (P < .01) and decreased during the 12-month follow-up (P < .01). However, compared with the baseline records, there was still a significant increase in alveolar bone volume (P < .01).This modified PAOO technique may have advantages in terms of soft and hard tissue augmentation, facilitating extensive bone augmentation and allowing the simultaneous correction of vertical and horizontal defects in the labial aspect of the mandibular anterior area.