OBJECTIVES: This study aimed to analyze the application value of a modified tragus edge incision and transmasseteric anteroparotid approach to condyle reconstruction. METHODS: Condyle reconstruction was performed in 16 patients (9 females and 7 males) with modified tragus edge incision and transmasseteric anteroparotid approach. After regular follow-up, the function of condyle reconstruction was evaluated by clinical indicators, such as parotid salivary fistula, facial nerve function, mouth opening, occlusal relationship, and facial scar. The morphology of rib graft rib cartilage was evaluated by imaging indicators, such as panoramic radiography, CT, and three-dimensional CT image reconstruction. RESULTS: At 6-36 months postoperative follow-up, all patients had good recovery of facial appearance, concealed incisional scar, no parotid salivary fistula, good mouth opening, and occlusion. One case had temporary facial paralysis and recovered after treatment. Radiographic evaluation further showed that costochondral graft survived in normal anatomic locations. CONCLUSIONS The modified tragus edge incision and transmasseteric anteroparotid approach can effectively reduce parotid salivary fistula and facial nerve injury in condylar reconstruction. The surgical field was clearly exposed, and the incision scar was concealed without increasing the incidence of other complications. Thus, this approach is worthy of clinical promotion.
Male ; Female ; Humans ; Mandibular Condyle/surgery* ; Cicatrix/surgery* ; Fracture Fixation, Internal/methods* ; Mandibular Fractures/surgery* ; Oral Surgical Procedures/methods* ; Treatment Outcome

OBJECTIVES: The aim of this study was to compare the anterior and posterior occlusal plane characteristics of patients with different temporomandibular joint osseous statuses. METHODS: A total of 306 patients with initial cone beam CT (CBCT) and cephalograms were included. They were divided into three groups on the basis of their temporomandibular joint osseous status: bilateral normal (BN) group, indeterminate for osteoarthrosis (I) group, and osteoarthrosis (OA) group. The anterior and posterior occlusal planes (AOP and POP) of the different groups were compared. Then, the regression equation was established after adjusting for confounding factors, and a correlation analysis between the occlusion planes and other parameters was performed. RESULTS: SNA, SNB, FMA, SN-MP, Ar-Go, and S-Go were correlated with the occlusal planes. Relative to the BN and I groups, the FH-OP of the OA group increased by 1.67° on the average, FH-POP increased by 1.42° on the average, and FH-AOP increased by 2.05° on the average. CONCLUSIONS The occlusal planes were steeper in the patients with temporomandibular osteoarthrosis than in the patients without it, and the mandible rotated downward and backward. The height of the mandibular ramus, the mandibular body length, and the posterior face height were small. In clinical practice, attention should be given to the potential risk of temporomandibular joint osteoarthrosis in such patients. In addition, SNB, FMA, SN-MP, Ar-Go, S-Go, and occlusal planes had moderate correlations.
Humans ; Dental Occlusion ; Cephalometry ; Mandible ; Temporomandibular Joint Disorders/diagnostic imaging* ; Temporomandibular Joint/diagnostic imaging* ; Osteoarthritis/diagnostic imaging* ; Mandibular Condyle

Objective: To preliminarily explore the mechanism of tensile stress regulating endochondral osteogenesis of condyle by analyzing the expression profiles of significantly different microRNAs (miRNAs) in exosomes of rat mandibular condylar chondrocytes (MCC) under quiescent and cyclic tensile strain (CTS) conditions. Methods: Rat condylar chondrocytes were cultured under static and CTS conditions respectively (10 SD rats, male, 2 weeks old), and exosomes were extracted. The two groups of exosomes were named as control group and CTS group respectively. The differential expression miRNAs were screened by high-throughput sequencing. Bioinformatics analysis and prediction of target genes related to osteogenesis were performed by TargetScan and miRanda website. Results: The exosomes of rat condylar chondrocytes cultured under tensile stress showed a "double concave disc" monolayer membrane structure, the expression of CD9 and CD81 were positive, and the particle size distribution accorded with the characteristics of exosomes, which was consistent with that of static cultured rat condylar chondrocytes. A total of 85 miRNAs with significantly different expression were detected by high-throughput sequencing (P<0.05). The main biological processes and molecular functions of differential miRNAs were biological processes and protein binding, respectively. Kyoto Encyclopedia of Genes and Genomes (KEGG) database pathway enrichment analysis showed that there was significant enrichment in mammalian target of rapamycin (mTOR) signal pathway. The candidate target genes of miR-199a-5p include bone morphogenetic protein 3 (BMP3), endothelin converting enzyme 1, and miR-186-5p may target Smad8 and BMP3 to exert osteogenesis-related functions. Conclusions: Compared with static state, tensile stress stimulation can change the expression of miRNAs such as miR-199a-5p, miR-186-5p in the exocrine body of rat condylar chondrocytes, which can be considered as a mean to regulate the application potential of the exosomes.
Animals ; Male ; Rats ; Bone Morphogenetic Protein 3 ; Chondrocytes/metabolism* ; Mandibular Condyle ; MicroRNAs/metabolism* ; Rats, Sprague-Dawley ; Signal Transduction ; Stress, Mechanical

Dentofacial deformities secondary to condylar hyperplasiais a kind of disease presenting facial asymmetry, malocclusion, temporomandibular joint dysfunction, and other symptoms caused by non-neoplastic hyperplasia of the condyle. The etiology is still unknown, and currently, pre- and post-operative orthodontics accompanied by orthognathic surgery, temporomandibular joint surgery and jawbone contouring surgery are the main treatment methods. A personalized treatment plan was developed, considering the active degree of condyle hyperplasia, the severity of the jaw deformity, and the patient's will, to correct deformity, obtain ideal occlusal relationship, and regain good temporomandibular joint function. Combined with the author's clinical experience, the etiology, clinical and imageological features, treatment aims, and surgical methods of condylar hyperplasia and secondary dentofacial deformities were discussed in this paper.
Humans ; Dentofacial Deformities/pathology* ; Hyperplasia/pathology* ; Mandibular Condyle/surgery* ; Orthognathic Surgical Procedures ; Temporomandibular Joint/surgery*

OBJECTIVES: This study aimed to use modified articular disc anchorage in treating old irreducible temporomandibular joint (TMJ) disc displacement with perforation and rupture, as well as to explore its efficacy. METHODS: A total of 31 patients (34 sides) with 47 TMJ disc perforations who underwent surgical treatment in the Affiliated Stomatolo-gical Hospital of Nanchang University from January 2018 to December 2021 were selected. According to the location of disc perforation, it has five types: posterior disc perforation (typeⅠ), anterior disc perforation (typeⅡ), lateral disc perforation (type Ⅲ), composite disc perforation, and destruction disc perforation. The modified methods of disc anchoring were divided into two types according to the location of the perforation. TypesⅠandⅢ disc perforation were trea-ted by posterior anchoring method. For posterior ancho-ring, a screw was implanted into the posterolateral side of the condylar neck, and the disc was fixed on the screw by horizontal mattress suture. TypeⅡdisc perforation and compo-site disc perforation combined typeⅡperforation were treated by anterior and posterior double-anchoring method. For anterior anchoring, anchor screws or holes were placed at the anterior edge of the condylar neck, and horizontal mattress suture was performed at the posterior edge of the anterior perforation with an anchor wire. The articular disc was then fixed on the anchor screws or holes. For the posterior anchoring method, it was the same as the previous one. Paired t test was used to analyze the visual analog scale (VAS), maximum interincisal opening (MIO), and TMJ disorder index (CMI) of the patient before surgery and 1, 3, and 6 months after surgery. Disk-condyle position relationship by magnetic resonance imaging and postoperative quality of life in postoperative were analyzed. RESULTS: The incidence of perforation was 41.2% (14/34) in typeⅠ, 11.8% (4/34) in typeⅡ, 8.8% (3/34) in typeⅢ, 29.4% (10/34) in composite type, and 8.8% (3/34) in destruction type. The VAS, MIO, and CMI at 3, 6 months after operation significantly improved compared with those before operation (P<0.05). The effective reduction rate of disc was 96.77% (30/31). The quality of life at 6 months after surgery was 47.22±2.13, and the rate of excellent evaluation was 96.4% (27/28). CONCLUSIONS Modified articular disc anchorage achieves a good curative effect for treating temporomandibular joint disc perforation and rupture. Nevertheless, its long-term effect requires further observation.
Humans ; Temporomandibular Joint Disc/surgery* ; Quality of Life ; Joint Dislocations/surgery* ; Temporomandibular Joint Disorders/surgery* ; Magnetic Resonance Imaging/methods* ; Temporomandibular Joint/pathology* ; Mandibular Condyle

Objective:To investigate the relationship between idiopathic condylar resorption （ICR） and arch width disorder. Methods:Thirty-two patients with ICR and twenty patients without condylar resorption were enrolled according to the same inclusion criteria. They were divided into experimental group and control group. The experimental group was divided into unilateral ICR group and bilateral ICR group according to the affected side of condylar resorption, and then experimental group was divided into subgroups ICR Ⅰ, ICRⅡand ICR Ⅲ according to the degree of condylar resorption. Patients with no condylar resorption were used as a control group. The width of anterior, middle and posterior segments of dental arch on cone beam computed tomography（CBCT） was measured and the two groups of measured values were statistically analyzed. Results:Compared with the control group, the width of maxillary anterior, middle and posterior segments in ICR group was significantly reduced, and the difference was statistically significant（P<0.01）. But the width of mandibular segment was not significantly different from that in control group（P>0.05）. There was no significant difference in the width of anterior, middle and posterior dental arch between subgroups（P>0.05）. Conclusion:Almost all patients with ICR have malocclusion of maxillary and mandibular arch width, but there is no significant correlation between the malocclusion width and the severity of condylar resorption.
Humans ; Mandibular Condyle/diagnostic imaging* ; Dental Arch ; Bone Resorption ; Mandible ; Malocclusion

Objective: To measure and analyze parameters of the three-dimensional (3D) model of the condylar movement envelope surface (ES) and provide a reference for the design of the temporomandibular prosthesis. Methods: Thirty-four healthy adults aged (25.4±2.8) years were recruited from the Department of Oral and Maxillofacial Surgery, Peking University School and Hospital of Stomatology as subjects. There were 9 males and 25 females, most of them were university students and others outside the university have received undergraduate education or above. Condylar movement ES were obtained using the previous method on the 3D trajectory of condyle. The simulations of condylar movement were projected according to opening movements, protrusion movements, and lateral movements respectively. The total area of the ES and the area proportions of models formed by above different mandibular movements were measured and calculated. The adults' head and maxillofacial 3D models reconstructed by cone beam CT were registered with ES in Geomagic Studio. The inner and outer poles of the condyle, the corrective sagittal axis of the ES, and the median sagittal plane (MSP) were calibrated in registration models using Geomagic Studio, and the parameters were measured as follows: the anteroposterior and medialateral diameters of the condyle, the anteroposterior diameters and the transverse diameters (anterior, middle and posterior parts) of the ES, the angles between the corrective sagittal axis of the ES and MSP (ES-MSP). Pearson correlation analysis was performed by SPSS 24.0. Results: The total area of the ES was (760±133) mm², the opening movement part accounted for (63.3±15.2)%, the protrusion movement part accounted for (14.9±9.6)%, the lateral movement part accounted for (21.8±13.3)%. Parameter measurements were as follows: mediolateral diameters of condyle was (19.8±2.3) mm; anteroposterior diameter of the ES was (21.2±3.1) mm, the transverse diameters (anterior, middle and posterior parts) of the ES were (20.6±2.4), (20.4±2.4), (22.0±2.6) mm, respectively; the transverse diameters of the ES were about 2 mm larger than that of the condyle. The angle between the corrective sagittal axis of ES and the MSP was 6.8°±6.2°. The coefficient of variation (CV) in these parameters showed: CV of the transverse diameters (anterior, middle and posterior parts) of the ES and mediolateral diameter of the condyle were 0.98, 0.99, 0.93, respectively (P<0.001). CV of aera of ES and mediolateral diameter of the condyle was 0.64 (P=0.002). CV of aera of ES and anteroposterior diameter of ES was 0.62 (P=0.004). Conclusions: The 3D envelope surface model formed by mandibular opening movements accounted for the largest proportion of the ES. The corrective sagittal axis of the ES was at an angle to the MSP, the transverse diameters (anterior, middle and posterior parts) of the ES were approximately 2 mm larger than the mediolateral diameter of the condyle, the transverse diameters (anterior, middle and posterior parts) of the ES were highly positively correlated with the mediolateral diameter of the condyle.
Humans ; Adult ; Male ; Female ; Mandibular Condyle ; Cone-Beam Computed Tomography ; Mandible ; Movement ; Temporomandibular Joint

Objective: To investigate the shape and position changes of temporomandibular joint (TMJ) in adult skeletal class Ⅱ malocclusion with high angle patients after vertical mandibular control, and the correlation between vertical mandibular changes and condylar position changes. Methods: Twenty adult skeletal class Ⅱ malocclusion with high angle patients [6 males and 14 females, aged (21.4±2.4) years] who underwent extraction treatment and active vertical control in the Department of Orthodontics, Lanzhou University Stomatological Hospital from October 2017 to November 2020 were selected. Cone-beam CT data of the patient before and after treatment were imported into Invivo Dental 5.0 software for three-dimensional reconstruction and correction, and the vertical index of mandible in reconstructed lateral cephalogram (mandibular plane angle, posterior anterior height ratio, mandibular true rotation angle) were measured. Incisal angle and variables of condyle shape, position and articular fossa shape were measured. Paired t test was performed on the results before and after treatment, and the correlation between mandibular vertical changes and condylar position changes was determined by Pearson correlation coefficient calculation. Results: After treatment, the overbite and overjet were within normal range, and the vertical height of the molars was controlled. Compared with the measurement before treatment, mandibular plane angle and mandibular true rotation angle were decreased by 2.05°±1.22° (t=7.60, P<0.001) and 1.42°±1.92° (t=3.54, P=0.002), respectively. The posterior anterior height ratio was increased by (1.89±3.32)% (t=2.56, P=0.019). After treatment, the mediolateral diameter of condyle, the anteroposterior diameter of condyle, the maximum cross-sectional area of condyle, the height of condyle head, the width of articular fossa, the depth of articular fossa and the articular nodular angle were increased by (0.55±0.76) mm (t=-2.73, P=0.015), (0.27±3.51) mm (t=-3.23, P=0.006), (6.01±7.36) mm² (t=-2.80, P=0.013), (0.33±0.72) mm (t=-2.14, P=0.046), (0.56±0.93) mm (t=-2.37, P=0.032), 0.33 (0.14, 0.51) mm (Z=-2.76, P=0.006) and 1.50°±2.40° (t=-2.44, P=0.028), respectively. The internal condylar space and the external condylar space were decreased by (0.33±0.49) mm (t=2.31, P=0.035) and (0.20±0.23) mm (t=3.58, P=0.003), respectively. Before orthodontic treatment, 6 patients were with anterior displacement of the condyle, 7 patients with central position of the condyle, and 7 patients with posterior displacement of the condyle. After correction, patients who were with central position of the condyle have not changed much. The posterior displaced condyle in 2 patients and anterior displaced condyle in 3 patients became in central position after treatment. The joint space index was closer to the central position in 3 patients with anterior displacement and 3 patients with posterior displacement. The position of condyle in 1 patient with posterior displacement and 1 patient with anterior displacement remained basically unchanged. There was a significant negative correlation between the change of the posterior-anterior height ratio and the change of the internal condylar space in patients (r=-0.52, P=0.019), and a low correlation with the contral condylar space and the external condylar space(r=-0.48, P=0.031; r=-0.47, P=0.035). Conclusions: Skeletal class Ⅱ malocclusion with high angle adult patients achieved normal overbite and overjet and remodeling of condyle and articular fossa occurred after orthodontic treatmnet and vertical control. There was a certain negative correlation between the change of posterior-anterior height ratio and the change of condylar position.
Adult ; Female ; Humans ; Male ; Cone-Beam Computed Tomography ; Malocclusion, Angle Class II/diagnostic imaging* ; Mandible/diagnostic imaging* ; Mandibular Condyle/diagnostic imaging* ; Overbite ; Temporomandibular Joint/diagnostic imaging*

Objective: To observe the different imaging manifestations of condylar sclerosis in temporomandibular joint osteoarthrosis and explore the imaging significance of condylar sclerosis. Methods: From January 2018 to December 2020, 50 patients with temporomandibular joint condylar sclerosis were examined by cone-beam CT (CBCT) and underwent spiral CT, MRI and radionuclide bone imaging at the Department of Oral and Maxillofacial Surgery in General Hospital of Chinese PLA. There were 15 males and 35 females aged from 16 to 65 years with age of (42.7±14.5) years. The imaging manifestations of CBCT, spiral CT, MRI and radionuclide bone imaging, joint disc displacement and abnormal bone metabolism of condylar sclerosis were analyzed. And the area of condylar sclerosis was graded according to the image of CBCT. Results: A total of 50 patients were included, including 38 unilateral condylar sclerosis, 12 patients with bilateral condylar sclerosis, the total condylar sclerosis were 66. There was no significant difference between the detection rate of further spiral CT (95.5%, 63/66) and CBCT (100.0%, 66/66) (corrected χ²=1.36,P=0.244). The area of condylar sclerosis was (35.5±4.5) mm², ranged from 1 to 100 mm². In addition, spiral CT showed more clearly condylar sclerosis than CBCT. Sclerosis can occur in all parts of condyle, mainly in the upper middle region (68.2%,45/66) in coronal position and in the upper front region (71.2%,47/66) in sagittal position. Fifty-seven condylar sclerosis were detected by MRI, including 4(4/19) condylar sclerosis less than 4 mm². There was significant difference in the displacement of temporomandibular joint disc between the sclerotic side and the non sclerotic side (χ²=10.09, P=0.006). MRI display the condylar sclerosis showed low signal (56/62), followed by high signal (5/62) and medium signal (1/62). Radionuclide bone imaging showed that 4 of the 38 patients with unilateral condyle sclerosis had symmetrical bone metabolism, 34 had abnormal bone metabolism, and 21 patients had concentrated on the non-sclerotic side. Radionuclide bone imaging showed that 4 of the 38 patients with unilateral condyle sclerosis had symmetrical bone metabolism and 34 had abnormal bone metabolism. Conclusions: Spiral CT is more accurate than CBCT in terms of condyle sclerosis through different imaging analysis, and the detection rate of both is higher than MRI. Most of condylar sclerosis showed different degrees of low signal on MRI. The condylar sclerosis side is usually manifested by abnormal bone metabolism.
Male ; Female ; Humans ; Mandibular Condyle/diagnostic imaging* ; Sclerosis/diagnostic imaging* ; Temporomandibular Joint/diagnostic imaging* ; Temporomandibular Joint Disorders/etiology* ; Temporomandibular Joint Disc/diagnostic imaging* ; Cone-Beam Computed Tomography ; Temporomandibular Joint Dysfunction Syndrome ; Osteoarthritis/etiology* ; Magnetic Resonance Imaging

Objective: To investigate the imaging features of condylar cystic degeneration of temporomandibular joint (TMJ) by cone-beam CT (CBCT), spiral CT, MRI and radionuclide bone imaging. Methods: From January 2018 to December 2020, thirty-two patients with cyst-like lesions of condylein temporomandibular joint were examined by CBCT, spiral CT, MRI and radionuclide bone imaging at the Department of Oral and Maxillofacial Surgery in General Hospital of Chinese PLA. There were 12 males and 20 females involved, aged from 16 to 65 years with an average age of (33.9±12.5) years. The characteristics of CBCT, spiral CT, MRI and radionuclide bone imaging were analyzed. Condylar cyst like lesions were classified as type A and type B based on the presence or absence of surface bone defects. Condylar cyst like lesions were classified as type Ⅰ(yes) and type Ⅱ(no) according to the accompanying bone marrow edema-like lesions of the condyles. The incidence of condylar bone marrow edema, disc displacement and abnormal bone metabolism were analyzed. Results: A total of 64 joint images of 32 patients were included, including 34 sides with TMJ cyst-like lesion and 6 sides with multiple cyst-like lesions,the total cyst-like lesions were 42. The largest diameter of cyst-like lesion ranged from 1.0 to 12.4 mm, with an average length of (3.7± 1.8) mm. There were 24 cases of type A TMJ cyst like lesion and 10 cases of type B cyst-like lesion. The detection rate of CBCT was 95.2% (40/42) and that of spiral CT was 100% (42/42), there was no significant difference (Calibration Chi-square=0.51, P=0.474). The detection rate of nuclear magnetic resonance was 80.1% (34/42), and the detection rate of cyst-like lesions less than 2 mm was 3/11. In the cyst like lesion side, there were 9 sides with anterior disc displacement with reduction, 20 sides with anterior disc displacement without reduction. In the non-cyst like lesion side, 10 sides with anterior disc displacement with reduction and 6 sides with anterior disc displacement without reduction. There was a significant difference in the displacement of the disc between cyst-like and non-cystic lesion side (χ²=7.80, P=0.005). MRI showed that 6 cases of cystic side[17.6% (6/34)] had bone marrow edema-like lesions (all type A), 1 case of non-cyst like lesions side [3.3% (1/30)] had bone marrow edema-like lesion, there was no significant difference between cystic and non-cystic lesions (Calibration Chi-square=2.04, P=0.153). There was a significant difference between type A and B cystic lesions (Fisher exact probability method, P=0.024). Radionuclide bone imaging showed abnormal bone metabolism in 26 patients in the cyst-like lesion side and 5 patients in the non-cyst like lesion side (χ²=22.82, P<0.001). Conclusions Multi-slice Spiral CT could detect the cyst-like lesion of TMJ condyle in the early stage, which is different from the large joint. And the formation mechanism may vary from the different classifications.
Adolescent ; Adult ; Aged ; Cysts ; Female ; Humans ; Joint Dislocations ; Magnetic Resonance Imaging ; Male ; Mandibular Condyle/diagnostic imaging* ; Middle Aged ; Multimodal Imaging ; Temporomandibular Joint/diagnostic imaging* ; Temporomandibular Joint Disc ; Temporomandibular Joint Disorders/diagnostic imaging* ; Young Adult