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Background: The aim of this study was to evaluate the condylar morphological changes after orthodontic treatment in adult patients with Class II malocclusion using a Cone-beam computed tomography (CBCT). Methods: Images of twenty-eight adult patients with Class II malocclusion who have no temporomandibular symptoms were involved in this study. To analyze the post-treatment changes in condylar morphology, mimics 17.0 software was used to measure several values and reconstruct the three-dimensional condyle, including height of the condyle, area and bone mineral density of the maximum axial and sagittal section, volume and bone mineral density of the three-dimensional condyle and condylar head before and after orthodontic treatment. Using SPSS 19.0 software package Paired t-test was applied for comparison of condylar morphology analysis between pre-treatment and post-treatment. Results: Height of condylar head increase significant (P <.05). Bone mineral density showed a decrease in the maximum axial and sagittal section, three-dimensional condyle and condylar head (P <.01). Evaluation of volume revealed that volume of both condyle and condylar head decrease considerably (P <.05). No significant difference was detected in other values ((P >.05). Conclusion: Condylar volume decreased and height of condylar head have changed, so we speculated that adaptive bone remodeling of the condyle occurs. [ABSTRACT FROM AUTHOR]

Purpose: The purpose of this article is to discuss the effective management of mandibular fractures in pediatric patients during the growing phase of the mandible using splint fiber and ligature wire. Methods: A retrospective study examined pediatric patients with mandibular fractures who were treated using the splint (Quartz) fiber and ligature wire technique at the Stomatology Hospital of Xi'an Jiaotong University from August 2021 to January 2023. Data on gender, age, location or site of the fracture, and development of tooth stage were collected from the patient's medical records. Descriptive statistics were used to analyze the data and evaluate the effectiveness of the splint (Quartz) fiber technique for treating mandibular fractures in pediatric patients. Results: Out of 256 subjects, 6 pediatric patients with mandibular fractures were selected, resulting in an incidence rate of 2.34% with an equal sex ratio. Mental or symphysis fracture was the most common site for fracture in children, accounting for 100% of cases. Right mandibular angle fracture was observed in 16.7% of patients, while 50% of the group (3 individuals) suffered from left condylar fracture and 16.7% had a bilateral condylar fracture. Treatment with Quartz splint fiber and circumdental arch wiring using ligature wire was successful with no observed post-treatment complications or malocclusion. The splint fiber was worn for 30 days and the circumdental arch wiring was for the same. Healing of bone fracture yields good results after 12 weeks. Follow-up care is crucial to monitor for complications, in this study, no post-treatment complications were observed. Conclusion: The treatment of pediatric mandibular fractures is complex and requires careful consideration of various factors. Conservative management should be the first choice, with open reduction and internal fixation reserved for specific cases. The use of quartz splint fiber and ligature wire is an effective treatment option for stabilizing the mandible and providing occlusal stability in growing children. A fiber splint along with ligature wire can also be used as an alternative treatment to avoid any adverse effects on the growth and development of the mandible and permanent teeth. A multidisciplinary approach is essential to achieving the best outcomes for pediatric patients with mandibular fractures. [ABSTRACT FROM AUTHOR]

Objectives: Morphological study is a common approach in the field of anterior disc displacement (ADD) pathology; however, analysis based on three-dimensional reconstructive imaging has not been investigated. This study investigated the association between ADD and the status of the mandibular condyle and articular fossa. Methods: Thirty-four patients were divided into three groups: normal articular disc position (NADP), anterior disc displacement with reduction (ADDwR), and anterior disc displacement without reduction (ADDwoR). Multiple grouped comparisons of three different disc statuses were performed by Kruskal–Wallis H test and variance analysis respectively. Receiver-operating characteristic curve was plotted to assess the diagnostic efficacy of the morphological parameters. Multivariate logistic regression analysis was used to investigate the interfering factors of ADD. Results: The condylar volume (CV) and condylar superficial area (CSA) in the NADP, ADDwR, and ADDwoR groups exhibited obvious changes (P < 0.05). Both CV and superior joint space (SJS) presented a good diagnostic accuracy for NADP-ADDwoR [area under the curve (AUC)CV = 0.813; AUCSJS = 0.855)], and ADDwR-ADDwoR (AUCCV = 0.858; AUCSJS = 0.801). CSA presented a good diagnostic accuracy for ADDwR-ADDwoR (AUC = 0.813). A multivariate logistic ordinal regression model showed that the CV [odds ratio (OR) = 1.011; regression coefficient (RC) = 0.011, P = 0.018], SJS (OR, 8.817; RC = 2.177; P < 0.001), and medial joint space (MJS) (OR, 1.492; RC = 0.400; P = 0.047) had a significantly impact on the groups. Conclusion: CV, CSA, SJS, and MJS were significantly associated with the different disc status, and the condyle in ADD exhibited 3-dimensionally altered dimensions. They could be considered as promising biometric markers to assess the ADD. [ABSTRACT FROM AUTHOR]

BACKGROUND: The surgical method for knee valgus deformity is osteotomy around the knee joint or total knee arthroplasty. Osteotomy around the knee joint needs three-dimensional shaping. The type of artificial total knee arthroplasty prosthesis and the degree of matching with the knee joint affect the long-term effect after arthroplasty. Femoral condyle osteotomy shaping usually requires the support of femoral condyle data. Nowadays, prosthesis systems designed by westerners have a relatively high usage rate in China, but cannot achieve the best results in the Chinese. OBJECTIVE: To explore the anatomical abnormalities of the femoral condyle, and provide anatomical data for total knee arthroplasty or osteotomy of knee valgus deformity METHODS: Totally 41 adult patients (53 knees) with knee valgus deformity were detected with CT scan. The obtained images were imported into Mimics 17.0 software, and digital three-dimensional model was established. The anatomical parameters were measured, and the distribution and correlation were analyzed. The knee joint parameters between knee valgus deformity patients and healthy normal knee in single deformity patients (control group, n=29) were compared. RESULTS AND CONCLUSION: (1) Compared with the control group, epicondylar angle was not significantly different in the valgus group (P > 0.05). Medial mechanical femoral angle, distal condylar angle, and poster condylar angle were significantly increased in the valgus group (P < 0.05). (2) Measurement results of the surface profile of the femoral condyle showed that femoral condyle data were significantly lower in the valgus group than that in the control group (P < 0.05). No significant difference in femoral medial condyle data was found between the valgus and control groups (P > 0.05). (3) The distance between the center of the femoral condyle and the condyle line of the femoral condyle was significantly lower in the valgus group than that in the control group (P < 0.05). (4) These findings indicate that the morphological changes of the femoral lateral condyle of adult secondary knee valgus deformity are more significant, but the morphological changes of the femoral medial condyle are not obvious. The femoral condyle axis is used as a reference for adult secondary valgus total knee arthroplasty. The data obtained can help intraoperative positioning and improve the treatment effect. [ABSTRACT FROM AUTHOR]

While the morphology and evolution of the quadrate among early birds and through the evolutionary origin of birds is not well known, we add to knowledge about that past diversity through description of the morphology of the quadrate in the unusually elongate skull of the Cretaceous enantiornithine bird Longipteryx chaoyangensis. The lateral and caudal surfaces of the quadrate are well exposed in two specimens revealing morphologies typical of early birds and their dinosaurian close relatives like a small otic head and two mandibular condyles. However, both skeletons exhibit quadrates with a unique, enlarged lateral crest that has not been previously described among Mesozoic birds. It is possible that the rostral surface of this lateral expansion served as the origination site for enlarged jaw musculature in a manner similar to the enlarged subcapitular tubercle in extant galloanserine birds. The caudally concave surface of the quadrate likely reflects some aspect of cranial pneumaticity, with its shape and position reminiscent of quadrates found in close non‐avialan maniraptoran relatives. It is possible that this lateral crest has a wider distribution among enantiornithines and other early birds and that the crest has been misidentified as the orbital process in some more damaged specimens. In addition, the enlarged lateral mandibular condyle (relative to the medial condyle) differs from the condition typically reported among enantiornithines and could indicate a difference in jaw function or mechanics in this bird with an elongated rostrum, or simply misinterpretations of morphology. Further examination of the quadrate in temporally early and phylogenetically stemward birds, along with their close outgroups, could greatly impact the study of several different aspects of bird biology including assessment of phylogenetic relationships, interpretation of the function and kinematics of the skull, reconstruction of foraging paleoecology, and evolution of skull morphological diversity among Mesozoic birds. [ABSTRACT FROM AUTHOR]

The purpose of this study was to propose a machine learning model and assess its ability to classify TMJ pathologies on magnetic resonance (MR) images. This retrospective cohort study included 214 TMJs from 107 patients with TMJ signs and symptoms. A radiomics platform was used to extract (Huiying Medical Technology Co., Ltd., China) imaging features of TMJ pathologies, condylar bone changes, and disc displacements. Thereafter, different machine learning (ML) algorithms and logistic regression were implemented on radiomic features for feature selection, classification, and prediction. The following radiomic features included first-order statistics, shape, texture, gray-level cooccurrence matrix (GLCM), gray-level run length matrix (GLRLM), and gray-level size zone matrix (GLSZM). Six classifiers, including logistic regression (LR), random forest (RF), decision tree (DT), k -nearest neighbors (KNN), XGBoost, and support vector machine (SVM) were used for model building which could predict the TMJ pathologies. The performance of models was evaluated by sensitivity, specificity, and ROC curve. KNN and RF classifiers were found to be the most optimal machine learning model for the prediction of TMJ pathologies. The AUC, sensitivity, and specificity for the training set were 0.89 and 1, while those for the testing set were 0.77 and 0.74, respectively, for condylar changes and disc displacement, respectively. For TMJ condylar bone changes Large-Area High-Gray-Level Emphasis, Gray-Level Nonuniformity, Long-Run Emphasis Long-Run High-Gray-Level Emphasis, Flatness, and Volume features, while for TMJ disc displacements Average Intensity, Sum Average, Spherical Disproportion, and Entropy features, were selected. This study has proposed a machine learning model by KNN and RF analysis on TMJ MR images, which can be used to classify condylar changes and TMJ disc displacements. [ABSTRACT FROM AUTHOR]

Objective: To investigate the arthroscopic temporomandibular joint disc reduction on the outcome of orthodontic patients with anterior disc displacement without reduction. Methods: From January 2012 to December 2021, forty treated orthodontic patients with anterior disc displacement without reduction (unilateral/bilateral) and no obvious articular cartilage absorption were selected from Department of Orthodontics, Shanghai Ninth People's Hospital, Shanghai Jiao Tong University School of Medicine. The patients were (17.5±3.8) years old (12-25 years old), including 8 males and 32 females. Twenty patients who had completed arthroscopic temporomandibular joint disc reduction were included in the control group, and twenty patients with untreated temporomandibular joint disc were included in the experimental group. Model measurement (including overjet, etc.), cephalometric analysis (including ANB angle, which was formed by subspinale, nasion and supramental, etc.) and temporomandibular joint magnetic resonance imaging (including measurement of the condyle height of the displacement sides) were used to compare the difference of two groups. Objective grading system was used to evaluate the efficacy of orthodontic treatment. Results: The overjet of the experimental group and the control group after orthodontic treatment was (2.19±0.76) and (1.92±0.94) mm, respectively. Both two groups achieved ideal overjet with no statistical difference ( t= 1.02, P= 0.314). The ANB angle difference before and after treatment in the control group (-1.97°±2.87°) was greater than that in the experimental group (0.09°±1.82°), and the difference was statistically significant ( t= 2.72, P= 0.010). The variation of condyle height before and after treatment was (0.30±1.11) mm in the experimental group and (0.82±1.25) mm in the control group, with no statistical significance ( t= 1.80, P= 0.076). The post-treatment objective grading system scores of the experimental group and the control group were 21.00 (16.00, 24.00) and 21.00 (17.00, 25.00), respectively, which had no statistical difference ( U =0.24, P= 0.808). Conclusions: In orthodontic patients with anterior disc displacement without reduction and no obvious articular cartilage absorption, whether displaced discs are repositioned after arthroscopic surgery has no significant effect on the orthodontic treatment outcome.

PURPOSE: To evaluate and compare the morphology, and position of the glenoid fossa in patients with Class Il malocclusion associated with mandibular retrusion and Class I malocclusion in the permanent dentition. METHODS: A sample of 26 subjects (12 males, 14 females, average age 13.4 years) with skeletal and dental Class II malocclusion associated with mandibular retrusion, was compared with a matched group of 31 subjects(12 males, 19 females, aged 12.9 years) with skeletal and dental Class I relationships. The lateral cephalograms were traced and the cephalometric analysis was taken by Nemotec Dental Studio 2006 software before orthodontic treatment. The comparisons between the two groups on the cephalometric measures for the assessment of glenoid fossa were performed by means of an independent samples t test using SPSS 15.0 software package. The correlation and regression analysis was also performed within the measures in the Class II group. RESULTS: The results showed there was significant difference of Wits, GF/Ptm-FH and GF-FMN between the two groups (P<0.01). There was a significant correlation between the GF-FMN vs. AOBO, GF-FMN vs. GF/S- FH, GF/S-FH vs.GF/Ptm-FH, S/Ptm-FH vs. GF/Ptm-FH in the Class II group. The regression equations of the GF-FMN vs. AOBO and GF-FMN vs. GF/S-FH were also obtained (P<0.05). CONCLUSIONS: The Class II malocclusion associated with mandibular retrusion patients have a posteriorly displaced glenoid fossa compared with Class 1 patients. Cephaiometric measurement is a useful tool to evaluate the glenoid fossa morphology and position. Supported by Research Fund of Science and Technology Committee of Shanghai Municipality (Grant No.08DZ2271100). [ABSTRACT FROM AUTHOR]

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., (Copyright © 2020 European Association for Cranio-Maxillo-Facial Surgery. Published by Elsevier Ltd. All rights reserved.)

Objective: Mandibular condyle injury usually results in malocclusion and disharmony of facial growth in growing children. This study aimed to evaluate the long-term effects of autogenous coronoid grafts on the facial growth of children with unilateral temporomandibular joint (TMJ) ankylosis who underwent mandibular condyle reconstruction., Methods: Ten growing patients with unilateral bony TMJ ankylosis admitted in West China Hospital of Stomatology, Sichuan University between January 1st, 2008 and December 31st, 2016 were followed up and evaluated. These patients include three males and seven females with ages ranging from 5 years to 12 years at the time of surgery. Each patient underwent gap arthroplasty, condyle reconstruction with ipsilateral coronoid, and interposition of the pedicled temporalis fascial flap in a single operation. The postoperative follow-up ranged from 3 years to 8 years with an average of 4.9 years. Postoperative panoramic radiographs determined the growth of the mandibular height and length on the affected side and compared it with those of the healthy side., Results: All patients recovered uneventfully after surgery. At the end of follow-up period, the maximal mouth opening ranged from 32 mm to 41 mm with an average of 35.6 mm. Mandibular height and length continued to grow after the successful treatment of ankylosis using autogenous coronoid grafts for condyle reconstruction. However, growth deficit still existed. The final ramus height and mandibular length of the affected side at the end of follow-up increased by 25.3% (P<0.05) and 26.1% (P<0.05), respectively, compared with the initial values measured immediately after surgery. Growth rates of ramus height and mandibular length of the affected side were 47.1% and 27.2% lower (P<0.05) than those of the healthy side, respectively., Conclusions: Mandibular height and length continued to grow after the successful treatment of ankylosis by using autogenous coronoid grafts for condyle reconstruction. However, growth deficit still existed. The growth rate of the affected mandible was reduced compared with that of the undisturbed side even after treatment of ankylosis.

Purpose: Although bioresorbable materials have begun to be applied in the clinic, they are used primarily in children with fractures; thus, there are few reports of their application for treatment of condylar fractures. This study evaluated the effect of the application of bioresorbable plates and screws for patients with condylar fractures, assisted by digital preoperative planning., Materials and Methods: This was a prospective interventional study. The sample was composed of 46 patients treated at the School of Stomatology of the China Medical University (Shenyang, China) from October 2016 through May 2018 for condylar fractures alone or in combination with other facial fractures. All patients underwent confirmatory preoperative computed tomography (CT) to obtain Digital Imaging and Communications in Medicine (DICOM) format data for preoperative designing. By digital designing, the authors confirmed operative plans for each patient. All 46 patients underwent bioresorbable osteosynthesis and underwent repeat CT on postoperative day 3. Postoperative clinical assessments included postoperative positions of the fracture segments, maximal mouth opening, lateral excursion movements, occlusal status, and patient satisfaction. These variables were used to assess postoperative efficacy., Results: The sample was composed of 46 patients who had open reduction with internal fixation on 52 sides. At the 3-month follow-up visit, the proportions of patients who were satisfied with the results and who achieved stable occlusion, appropriate maximal mouth opening, and flexible lateral excursion movement were 97, 100, 66, and 95%, respectively. One patient sustained postoperative displacement of a condylar fracture fragment, as confirmed by repeated CT. He was lost to follow-up at 3 months postoperatively., Conclusion: The results of this study suggest that open reduction treatment of condylar fractures implanted with bioresorbable materials in combination with digital preoperative designing is an effective method for managing patients in clinical practice., (Copyright © 2019. Published by Elsevier Inc.)

Objective: This study aimed to analyze the treatment for mandibular coracoid fractures retrospectively., Methods: A retrospective study on 37 patients with mandibular coracoid fractures treated at Department of Traumatic and Plastic Surgery, West China Hospital of Stomatology, Sichuan University from January 2010 to December 2015 was conducted. Eleven patients were treated conservatively, and 26 patients underwent surgical restoration and internal fixation. Mouth opening and pain degree were used as indicators to analyze treatment results., Results: The 37 cases of coracoid fractures accounted for 3.18% of the total mandibular fractures. The average age of patients was 38.05 years. Satisfactory results were obtained in both treatments. A considerable change in the degree of mouth opening before and after 6 months was found in the two groups. The pain degree before treatment and 1 day after operation, 1 day and 4 weeks after operation, and 4 weeks and 6 months after operation indicated that the two groups did not significantly differ. However, substantial changes between the two groups were found before treatment and 6 months after operation., Conclusions: Conservative treatment is recommended for patients with linear, temporalis muscle-located, and non-displaced coracoid fractures. Surgical treatment is recommended for patients with large fractures and those with accompanying zygomatic arch and mandible fractures.