The relationship between the articular disc in magnetic resonance imaging and the condyle in cone beam computed tomography: A retrospective study.

BACKGROUND: The authors retrospectively studied the relationship between the morphology and position of the articular disc in magnetic resonance imaging (MRI) and the morphology and position of the condyle in cone beam computed tomography (CBCT), with the purpose for providing reference for clinical diagnosis and treatment of temporomandibular disorders (TMD). METHODS: Patients with both CBCT and MRI imaging data were studied retrospectively, excluding TMJ tumour, fracture, severe condylar morphological abnormalities, non-intercuspal position, and poor quality images. A total of 744 temporomandibular joints (TMJs) from 372 patients were included, with the mean age of 25.94±11.04Y (75 males and 297 females). T2-weighted image (T2WI) of MRI imagings were used to evaluate disc morphology and disc displacement, while CBCT was obtained to evaluate the condylar bone and sagittal condylar position. Data were analysed by Pearson Chi square test and Spearman correlation coefficient. RESULTS: THE DISTRIBUTION OF 744 TMJS IS AS FOLLOWS: 1) DISC MORPHOLOGY: contracture (37.1 %) > biconcave (32.9 %) > irregular (18.5 %) > lengthened (11.4 %); 2) disc position: ADDWoR (48.3 %) > NA (26.9 %) > ADDWR (21.6 %) > PDDWR (2.8 %) > PDDWoR (0.4 %); 3) condylar position: concentric (43.7 %) > posterior (37.6 %) > anterior (18.7 %); 4) condylar bone: normal (63.4 %)> abnormal (36.6 %). There were significant differences in the distribution of disc morphology and disc position between the sex (P < 0.05). There were significant differences in the distribution of disc position and condylar morphology amongst the age groups (P < 0.05). There were significant differences in the distribution of disc position, condylar position and condylar morphology amongst disc morphology (P < 0.05), and there were positive correlation between disc position(r = 0.703, P = 0.000), the score of condyle (r = 0.478, P = 0.000) and disc morphology respectively. There were significant differences in the distribution of disc position and condylar position amongst condylar morphology (P < 0.05). There was a positive correlation between disc position and condyle morphology (r = 0.413, P = 0.000), and a negative correlation between condyle position and condyle morphology (r=-0.152, P = 0.000). There were significant differences in the distribution of disc position amongst condylar position (P < 0.05), but there was no linear correlation (P = 0.159). CONCLUSIONS: The mutual distribution of disc morphology, disc position, condylar morphology and condylar position was statistically significant. Disc displacement did not necessarily lead to condylar bone changes, but 92.7 % TMJs with condylar bone abnormalities had disc displacement. TRIAL REGISTRATION: This study was retrospectively registered on 28/03/2022 and endorsed by the Ethics committee (LCYJ2022014).

Effectiveness of Occlusal Splint Therapy in Moderating Temporomandibular Joint Disorders With Joint Displacement: A Retrospective Analysis Using Cone Beam Computed Tomography.

Background Temporomandibular joint disorders (TMD) represent a prevalent group of conditions impacting the temporomandibular joint. Among the therapeutic interventions, occlusal splint therapy has gained recognition for its potential to address TMD symptoms, particularly in cases involving joint displacement. Objective This study aims to investigate the effectiveness of occlusal splint therapy in cases of moderate TMD with joint displacement, focusing on changes in condylar position, joint morphology, and patient-reported outcomes. Methods A retrospective analysis was conducted involving 148 participants who underwent occlusal splint therapy between January 2018 and December 2020. Data were collected through cone beam computed tomography (CBCT) imaging for precise assessments of condylar position and joint morphology. Ethical approval was obtained, and participants provided informed consent. Baseline characteristics, medical history, and TMD severity were recorded. Occlusal splint therapy included individualized fabrication, occlusal analysis, adjustments for optimal fit, and prescribed wear schedules. Follow-up included CBCT scans at specified intervals (three months and six months), with participant-reported outcomes collected. The data analysis was conducted using IBM SPSS Statistics for Windows, Version 22.0 (Released 2013; IBM Corp., Armonk, NY, USA). Paired t-tests or nonparametric equivalents were employed to assess changes in condylar position and joint morphology. Subgroup analyses were conducted to explore potential factors influencing treatment outcomes. The significance level was set at p < 0.05 for all statistical tests. Results The entire cohort (n = 148) had a mean age of 32.5 years (± 8.1), with a balanced gender distribution. Changes in condylar position revealed a statistically significant improvement (p = 0.03), with a mean decrease of 0.2 mm posttreatment. Joint morphology changes indicated increased joint space width (p = 0.01), improved disc position (p = 0.02), and nonsignificant alterations in bony structures (p = 0.10). Patient-reported outcomes demonstrated significant improvements in pain levels, jaw functionality, and satisfaction (all p < 0.001). Age and gender subgroup analyses showed consistent improvements in condylar position, joint morphology, and patient-reported outcomes across different groups. Conclusion Occlusal splint therapy demonstrated effectiveness in improving condylar position, joint morphology, and patient-reported outcomes in cases of moderate TMD with joint displacement. The findings underscore the potential of occlusal splint therapy as a viable intervention for managing TMD, providing valuable insights for clinicians and researchers.

Investigation of the accuracy of dynamic condylar position: A model study.

OBJECTIVES: To evaluate dynamic condylar positions by integrating mandibular movement recording data and cone-beam computed tomography (CBCT) and to investigate its accuracy via dynamic model experiments. METHODS: A polyvinyl chloride skull model was utilized. A robot arm was used to operate the mandible to perform mouth opening, closing, protrusion, and lateral movements. A recording device, worn on the skull, was used to record the dynamic process and an optical position tracking (OPT) system was used to simultaneously trace the movements. A self-developed software module was used to evaluate the dynamic condylar position by integrating the dynamic tracing data and a virtual skull model derived from CBCT images. Errors were defined as differences between the dynamic coordinates of six landmarks around the condylar area derived from the software module (test) and OPT system (gold standard). RESULTS: The condylar position errors were 0.76 ± 0.31, 0.55 ± 0.15, and 0.68 ± 0.23 mm for mouth opening, bilateral, and protrusion movements, respectively. Furthermore, the errors for small, moderate, and large mouth opening movements were 0.62 ± 0.19, 0.69 ± 0.29, and 0.94 ± 0.31 mm, respectively. The errors for all movements, except for large mouth opening, were significantly less than 1 mm (P < 0.05). The error was not different from 1 mm in the large mouth opening movement (P > 0.05). CONCLUSIONS: Our developed method of achieving dynamic condylar position by integrating mandibular movement recording data and CBCT images is clinically reliable. CLINICAL SIGNIFICANCE: This study proved the reliability of evaluating dynamic condylar position using a commercial dynamic recording instrument and CBCT images.

Evaluation of condylar position in patients with malocclusion and changes in condylar position before and after orthodontic treatment using cone beam computed tomography / 口腔疾病防治

@#The functional health and stability of the oral and maxillofacial system is one of the basic goals of orthodontic treatment. Currently, it is believed that, in general, the condyle is located in the center of the joint fossa when the mandible is in an intercuspal position (ICP) in healthy normal people. At this time, the function of the temporomandibular joint (TMJ) is stable. Due to orthodontic tooth movement and subsequent occlusal changes, patients with malocclusion may experience related remodeling of the temporomandibular joint, especially changes in the position of the condyle. The position of the mandibular condyle is traditionally evaluated using a condylar position indicator. However, this method lacks consistency in obtaining condylar position changes. In recent years, in the clinical application of orthodontic treatment, cone beam computed tomography (CBCT) has become the first choice for examination. CBCT can accurately measure the interarticular space and determine changes in condylar position. This article reviews the CBCT assessment of condylar position and related research on condylar position changes in patients with malocclusion before and after orthodontic treatment. The literature review results indicate that there are differences in the condylar position of patients with different malocclusions, and the condylar position may also change before and after orthodontic treatment. With a lower radiation dose, CBCT has higher accuracy in evaluating the condylar position in patients with malocclusion who undergo orthodontic treatment, thus promoting further study of the mechanism of condylar position changes in patients with malocclusion in the future and providing more accurate and personalized guidance for patient treatment.

Digital jaw relation recording to evaluate a new vertical dimension of occlusion using CAD/CAM-fabricated tooth-colored splints: a case report.

Pronounced defects of the dental hard tissue can be caused by different etiologic factors. Most frequently, they are associated with changes in the vertical dimension of occlusion (VDO), which may also influence the condylar positions. These defects can lead to irreversible loss of tooth structure and have dramatic functional and esthetic consequences, often requiring complex rehabilitation. In this situation, CAD/CAM-fabricated occlusal splints made of tooth-colored polycarbonate are a proven and safe pretreatment approach in terms of esthetics and function. Rebuilding lost dental hard tissue to restore the occlusion and VDO to an adequate condylar position is a prerequisite for any sustainable and functional rehabilitation. In the future, digital systems will support this complex process, customizing it and making it simpler and more precise. The DMD-System (Ignident) provides patient-specific jaw movement data to optimize the CAD/CAM workflow. This system allows real movement patterns to be digitized and analyzed for functional and potential therapeutic purposes, integrating them into the dental and laboratory workflow. In the present case, the familiar tooth-colored CAD/CAM-fabricated occlusal splint is supplemented by digital centric jaw relation recording and individual movement data.

Comparison of imaging findings of 714 symptomatic and asymptomatic temporomandibular joints: a retrospective study.

BACKGROUND: The correlation between temporomandibular disorders (TMD) and imaging features remains unclear. This study compared the cone beam computed tomography (CBCT) and magnetic resonance imaging (MRI) features in the temporomandibular joints (TMJs) with and without TMD symptoms. METHODS: The participants were recruited from the TMJ Diagnosis and Treatment Center from March 2022 to September 2022. Condylar morphology and condylar position were evaluated by CBCT. Disc morphology, disc position, and joint effusion were evaluated by T2-weighted image of MRI. The Chi-Square test and binary logistic regression analysis were carried out. RESULTS: Eighty-two patients with bilateral symptoms, 196 patients with unilateral symptoms, and 79 asymptomatic participants received MRI and CBCT examination. There were significant differences in the distribution of sex, age, condylar morphology, condylar position, disc morphology, disc position, and joint effusion in symptomatic and asymptomatic TMJs (P < 0.05), which showed a positive correlation with symptoms (P < 0.05). In multiple logistic regression, 19-30-year-age group, > 30-year-age group, abnormal condylar morphology, posterior condylar position, disc displacement with reduction (DDWR), and disc displacement without reduction (DDWoR) were found to be statistically significant (P < 0.05). The odds of having symptomatic TMJ were 1.952 higher in the 19-30-year-age group and 1.814 higher in the > 30-year-age group when compared to those aged ≤ 18-year-age group. The odds of having symptomatic TMJ were 2.360 higher in persons with abnormal condylar morphology when compared to those with normal condylar morphology. The odds of having symptomatic TMJ were 2.591 higher in persons with posterior condylar position when compared to those with the normal condylar position. The odds of having symptomatic TMJ were 2.764 higher in persons with DDWR and 4.189 higher in persons with DDWoR when compared to those with normal disc position. The area under the curve of the model was 0.736 ± 0.019 (95% CI 0.700-0.773, P = 0.000), which indicated that the model has a good fitting effect. CONCLUSIONS: The imaging findings of TMJs were significantly different between symptomatic and asymptomatic TMJs. TMD is affected by multiple factors including > 19-year-age, abnormal condylar morphology, posterior condylar position, DDWR, and DDWoR, which could be risk factors for the development of TMD symptoms. Trial registration This study was retrospectively registered on 28/03/2022 and endorsed by the Ethics Committee of Affiliated Stomatology Hospital of Guangzhou Medical University (LCYJ2022014).

RECIPROCAL CLICKING LOCATION ANALYSIS IN THE INTRAARTICULAR TEMPOROMANDIBULAR DISORDERS AFTER AXIOGRAPHY INVESTIGATION.

OBJECTIVE: The aim: To investigate the peculiarities of hinge axis trajectories in patients with condyle-disc complex intraarticular Temporomandibular Disorders (TMD) and determine the average coordinates of the reciprocal clicking location by axiography. PATIENTS AND METHODS: Materials and methods: The results of axiographic examination of 151 patients (108 females and 43 males) with TMD confirmed by MRI were analyzed. This population included 44 persons with disc displacement with reduction (DDR), 45 persons with disc displacement with reduction and intermittent locking (DDRI), 62 persons with disc displacement without reduction (DDWR). Axiographic examination was carried out using CADIAX diagnostic device. Analysis of hinge axis movements was performed and the coordinates of articular disc reduction were determined. RESULTS: Results: The quality of hinge axis trajectories in persons with DDR, DDRI was defined mainly as average and in patients with DDWR as poor. Quantitative indicators of trajectories during protrusion-retrusion movements were not beyond the average level. The length of the mouth opening-closing trajectory in patients with DDRI and DDWR has shown a tendency to decrease. We found that on average the reciprocal closing clicking (disc reduction) occurs at a distance of 0-1.4 mm on the X-axis, 0.1-2.9 mm on the Z-axis, and 0-0.85 mm on the Y-axis. CONCLUSION: Conclusions: The obtained wide range of reciprocal clicking location parameters indicates the priority of a personalized approach when planning preliminary treatment in order to restore the disc-condylar complex of TMJ.

Evaluation of postoperative changes in condylar positions after orthognathic surgery using balanced orthognathic surgery system.

BACKGROUND: Many studies on maintaining the condyle in a normal or anatomical position during orthognathic surgery have been conducted to stabilize surgical outcomes and prevent iatrogenic temporomandibular joint complications. The aim of this study is to evaluate the changes in condylar positions after orthognathic surgery using virtual surgical planning via the balanced orthognathic surgery (BOS) system. METHODS: Postoperative changes in condylar position were retrospectively evaluated in 22 condyles of 11 patients with skeletal class III malocclusion who underwent orthognathic surgery using virtual surgical planning via the BOS system. The center point coordinates of the condylar head before and after orthognathic surgery were analyzed using voxel-based registration. RESULTS: Changes in the condylar position mainly occurred downward in the y-axis (-1.09 ± 0.62 mm) (P < 0.05). The change in the x-axis (0.02 ± 0.68 mm) and z-axis (0.01 ± 0.48 mm) showed no significant difference between before and after orthognathic surgery. CONCLUSION: These results indicate that the changes in the condylar positions after orthognathic surgery using virtual surgical planning via the BOS system mainly occurred downward in the y-axis, with slight changes in the x- and z-axes. The change in the condylar position after orthognathic surgery using the BOS system is clinically acceptable.

Does the horizontal condylar angle have a relationship to temporomandibular joint osteoarthritis and condylar position? A cone-beam computed tomography study.

BACKGROUND: The aim of the study was to evaluate the relationship between the horizontal condylar angle (HCA), temporomandibular joint osteoarthritis (TMJ OA), and condylar position on cone-beam computed tomography (CBCT) images. MATERIALS AND METHODS: Based on TMJ OA, joints were classified as affected and the unaffected. According to the OA condition of their joints, three groups of patients were formed: control group (n = 159, 41.1%), unilateral group (n = 121, 31.3%), and bilateral group (n = 107, 27.6%). In total, the HCAs of 774 TMJs of 387 patients were measured and their condylar positions were determined as concentric (n = 184, 23.8%), posterior (n = 338, 43.7%), and anterior (n = 252, 32.5%). RESULTS: The mean HCA of the bilateral group (22.7 ± 7.6°) was greater than those in both the control (19.5 ± 6.4°) and the unilateral (20.5 ± 6.5°) groups (p < 0.05). However, the difference was not statistically significant between the control and unilateral group (p > 0.05). In total patients, unlike the unilateral group, the affected joints had a greater mean HCA than the unaffected joints (p < 0.05). The mean HCAs of the joints according to the condylar position were as concentric: 20.6 ± 6.7°, posterior: 21.1 ± 7.8°, and anterior: 20.2 ± 7.9° (p > 0.05). CONCLUSIONS: While the HCA increased in the presence of TMJ OA, no relationship was found between HCA and three different condylar positions.

Oral rehabilitation following successful TMD treatment with condylar position changes: A case report.

BACKGROUND: A 31-year-old woman with crowns, fixed partial prostheses, and dental restorations complained of recurrent pain in the left and right temporomandibular joints during the last 2 years. CLINICAL PRESENTATION: The symptoms of temporomandibular disorder (TMD) resolved successfully after a 3-month-long treatment with a repositioning splint. Pre- and post-operative cone-beam computed tomography revealed slight changes in the condylar position after splint use. Minimally invasive oral rehabilitation guided by digital design was performed to maintain the acquired stable position. The status of the restorations was good, and the TMD symptoms did not relapse during the 3-year follow-up. CONCLUSION: This case report demonstrates the importance of a stable adapted condylar position after extensive prosthodontic treatment.

Evaluation of condylar position in anterior mandibular fractures using 3 dimensional miniplate osteosynthesis versus conventional miniplates: Randomized clinical trial.

To compare clinically and radiographically between the 3-D plates and the conventional two Champy's miniplates in the treatment of anterior mandibular fractures. It is a randomized clinical and radiographic comparative study between 2 equal groups of patients with isolated anterior mandibular fractures. Open reduction and internal rigid fixation was accomplished in the study group using 3D miniplates fixation while in the control group using the two Champy's miniplates. The 3D miniplate osteosynthesis consumed less operative time than the two miniplates osteosynthesis. Independent t-test revealed that the difference between the 2 groups was 8.4 ± 3.11 min. This difference was statistically significant (p=0.012). Occlusion was slightly disturbed in two patients in the study group in comparison to three patients in the control group. The difference between the 2 groups was not statistically significant (p=0.62). None of the cases of both groups showed mobility between the reduced and fixed fractured segments, immediately post-operatively and at the end of follow-up intervals. The 3D miniplate osteosynthesis (study group) recorded less intercondylar distance than two miniplates osteosynthesis (control group) immediately post-operatively and after 3 months. Independent t-test revealed that the difference between the 2 groups was not statistically significant, immediately postoperative (p=0.322) and after 3 months (p=0.263). Pre-operatively to 3 months postoperatively, the 3D miniplate osteosynthesis (study group) recorded a lower median percent increase in the intercondylar distance than the two miniplates osteosynthesis (control group). The difference between the 2 groups was not statistically significant (p=0.917). Regarding the intercondylar angle, the3D miniplate osteosynthesis (study group) recorded higher intercondylar angle than the two miniplates osteosynthesis (control group) immediately post-operative (p=0.333) and after 3 months (p=0.255). Independent t-test revealed that the difference between the 2 groups was not statistically significant. The 3-Dimensional strut miniplates should be considered an alternative for internal rigid fixation of anterior mandibular fractures for their ease of adaptation and insertion, while providing the advantage of reduced operative time compared to the conventional two Champy's miniplates.

Changes in condylar position after orthognathic surgery and its correlation with temporomandibular symptoms (TMD)- a prospective study.

The aim of the study was to assess the changes in the condylar position after orthognathic surgery (OGS) and its effect on temporomandibular disorders (TMD). A total of 37 dentofacial deformity patients included in the study who had undergone OGS were divided into three groups: Group I, Le Fort I maxillary advancement; Group II, bilateral sagittal split osteotomy (BSSO) mandibular advancement ± Le Fort I; and Group III, BSSO mandibular setback ± Le Fort I. Patients were evaluated clinically using Diagnostic Criteria for TMD and by radiography preoperatively and 6 months postoperatively. The positional changes in condyle were correlated with signs and symptoms of TMD. A total of 37 patients in three groups (Group I, 8 patients; Group II, 10 patients; and Group III, 19 patients) were evaluated. Overall, condyles had anterio-medio-inferior movement with 7 of 8 patients in Group I, 6 of 10 patients in Group II and 13 of 19 patients in Group III having ≤2 mm displacement. In angular changes, inward-anterio-medial movement was observed with 6 of 8 patients in Group I; about 5 of 10 patients, and 10 of 19 patients in Group II and III respectively had ≤5° change. Intragroup and intergroup comparisons showed insignificant changes in TMD and linear/angular movement (p ≥ 0.05). Pearson correlation coefficient was found to be nonsignificant on the radiographic and clinical comparison (p ≥ 0.05). Intrarater reliability (Kappa value) was found to be 0.83, confirming the results. Within the limitations of the study it seems that there are minimal linear and angular changes in condyle after orthognathic surgery that were not responsible for the development of temporomandibular disorders in the postoperative course.

Posición condilar y espacio articular témporomandibular valorado con tomografía Cone beam / Condylar position and Temporomandibular Joint Space analysis with Cone-beam tomography

Resumen Objetivo. Comparar posición condilar y espacio articular en articulación témporo-mandibular, en pacientes con y sin disfunción témporo-mandibular mediante tomografía Cone Beam. Métodos. Criterios diagnósticos de investigación para trastornos témporo-mandibulares Eje II, n=50 pacientes ambos sexos, edad comprendida 18 - 27 años. Muestra aleatoria n= 50 pacientes equivalente a 100 articulaciones, se obtuvo: n=25 pacientes sin disfunción témporo-mandibular, considerados asintomáticos 25 con y sin disfunción témporo-mandibulares, considerados sintomáticos. Mediante tomografía Cone Beam de articulación témporo-mandibular boca abierta - boca cerrada se avaluó de forma manual los espacios interarticulares. Resultados. El espacio condilar anterior en pacientes con y sin disfunción témporo-mandibular no presentó diferencia significativa, p=0,30. La posición condilar tampoco mostró diferencia significativa p=0,58. En pacientes con y sin disfunción témporo-mandibular (sintomáticos) la posición central y posterior del cóndilo (35,2%), pacientes con y sin disfunción témporo-mandibular (asintomáticos) la posición anterior y central fue más significativa (37,0%); seguido de la posición posterior del cóndilo (26,1%). Conclusión. No existe diferencia significativa en la posición condilar y el espacio interarticular en pacientes sintomáticos y asintomáticos.

Abstract Aim. To compare the condylar position and joint space of the temporomandibular join in individuals with and without temporomandibular dysfunction, using cone beam computed tomography (CBCT). Methods. Research Diagnostic Criteria for Temporomandibular Disorders Axis II (n= 50) patients both sexes, age 18 - 27 years. Random sample (n=50) patients equivalent to 100 joints, obtaining: n-25 patients without temporomandibular dysfunction, considered asymptomatic and 25 patients with and without temporomandibular dysfunction, considered symptomatic. By tomography Cone Beam of open mouth temporomandibular joint - closed mouth was manually evaluated the interarticular spaces. Results. The anterior condylar position space and condylar position not significantly different in induvials with and without temporomandibular dysfunction temporomandibular disorders p=0,30 and p=0,58, respectively. Conclusions. There is no significant difference in the condylar position and intraarticular.

Centric relation critically revisited-What are the clinical implications?

PURPOSE OF THE ARTICLE: Centric relation is a dental term that has undergone many alterations over the years, which in turn have led to significant clinical controversies. These continuing changes in the meaning of the term CR have not only led to confusion, but they also have resulted in a variety of unnecessary diagnostic and therapeutic procedures. Analysis of the dental literature reveals ongoing misunderstanding and disagreement regarding that term among both clinicians and academic dentists. MATERIALS AND METHODS: A search of the PubMed database was performed with the following search terms: "centric relation", "masticatory muscles", "maxillomandibular relationship" and "condylar position." Relevant literature from the past 70 years until the present day was meticulously scrutinised. RESULTS: As expected, the literature review on the topic of CR revealed a problematic pattern of changing definitions and clinical disagreements, all of which have had a significant impact on the practice of dentistry. CONCLUSION: There are semantic, conceptual and practical reasons for concluding that the term 'centric relation' is flawed. Those flaws have a significant impact on dental practice. Based on our analysis, argumentation is provided to conclude that the term 'centric relation' should be abandoned. Instead, it appears that every individual has a unique temporomandibular joint relationship which cannot be described by any singular term. In healthy dentate patients, this relationship is determined by the maximum intercuspation of the teeth and should therefore be considered as biologically acceptable.

Cone beam computed tomographic evaluation of the changes in condylar position in growing patients with unilateral posterior crossbite undergoing rapid maxillary expansion followed by fixed orthodontic therapy.

PURPOSE: This study aimed at assessing changes in condylar position (CP) in growing patients with unilateral posterior crossbite (UPC) undergoing rapid maxillary expansion (RME) followed by fixed orthodontic treatment (FOT) (experimental-group); and growing patients without posterior crossbite (PC) treated with FOT alone (control-group). METHODS: Cone beam computed tomography (CBCT) images were obtained before treatment (T0), 6 months after RME (T1) and after FOT (T2) for the experimental-group (n = 19); and at T0 and T2 for the control-group (n = 22). Condylar position-related measurements including the anterior joint space (AJS), superior joint space (SJS), posterior joint space (PJS), lateral position of condyle (LC) and condylar angle (CA) were measured. Non-parametric tests were used. RESULTS: On the crossbite side, significant increases were found in LC (P = 0.039) and CA (P = 0.007), and on the non-crossbite side significant increases were observed in SJS (P = 0.027) and LC (P = 0.001) between T0, T1 and T2 in patients with UPC. On the right and left sides in the control-group, significant increases were identified in LC (P < 0.001 and P = 0.012, respectively) between T0 and T2. CONCLUSIONS: In growing patients with UPC, RME followed by FOT is associated with significant changes in CP-related measurements.

Effect of deprogramming splint and occlusal equilibration on condylar position of TMD patients - A CBCT assessment.

Objective: Assessment of clinical symptoms and condylar position of TMD patients using CBCT imaging with deprogramming splint therapy and occlusal equilibration. The hypothesis tested was the alleviation of symptoms of TMD with possible changes in condylar position occurs with this treatment.Methods: The condylar position of 12 TMD patients was observed from CBCT images, and clinically, symptom severity score, mouth opening, and range of motion were compared pre- and post-treatment.Results: All patients reported a statistically significant decrease in the symptom severity score and increase in mouth opening and range of motion (p < .05). A significant decrease was only achieved in the left anterior joint space (p < .05).Conclusion: Deprogramming splint therapy and occlusal equilibration benefitted patients with a reduction in clinical symptoms, and minor changes in condylar position were observed.

The three-dimensional evaluation of positional change in mandibular condyle after intraoral vertical ramus osteotomy.

OBJECTIVES: The purpose of this study was to compare the changes of the condylar axis, the anteroposterior condylar position relative to the glenoid fossa, after intraoral vertical ramus osteotomy (IVRO). STUDY DESIGN: 21 patients diagnosed as skeletal class III malocclusion underwent IVRO and were followed according to the authors' postoperative management regimen. The three-dimensional positions of the condyles were evaluated by cone-beam computerized tomography (CBCT) at pre-op, post-op, and at follow-up. CBCT images were referenced to assess the condylar axis change and the anteroposterior condylar position in the glenoid fossa. A repeated-measures analysis of variance (P<0.05) also was performed. RESULTS: After surgery, both the axial condylar angles and the anteroposterior condylar position were significantly different (P<0.05). The coronal condylar axis rotated outwardly. The anteroposterior condylar position in the glenoid fossa had moved from the concentric to the anterior position. But the condyle changes between post-op and follow-up (P>0.05) were insignificant. CONCLUSIONS: With postoperative intermaxillary elastic traction, the condyles changed their positions physiologically for newly established jaw movement after IVRO.

Evaluation of Condylar Positional, Structural, and Volumetric Status in Class III Orthognathic Surgery Patients.

BACKGROUND AND OBJECTIVES: The need to evaluate the condylar remodeling after orthognathic surgery, using three-dimensional (3D) images and volume rendering techniques in skeletal Class III patients has been emphasized. The study examined condylar positional, structural, and volumetric changes after bimaxillary or single-jaw maxillary orthognathic surgeries in skeletal Class III patients using the cone-beam computed tomography. MATERIALS AND METHODS: Presurgical, postsurgical, and one-year post-surgical full field of view (FOV) cone-beam computed tomography (CBCT) images of 44 patients with skeletal Class III deformities were obtained. Group 1 underwent a bimaxillary surgery (28 patients: 24 females and 4 males), with mean age at the time of surgery being 23.8 ± 6.0 years, and Group 2 underwent maxillary single-jaw surgery (16 patients: 8 females and 8 males), with mean age at the time of surgery being 23.7 ± 5.1 years. After the orthognathic surgery, the CBCT images of 88 condyles were evaluated to assess their displacement and radiological signs of bone degeneration. Three-dimensional (3D) condylar models were constructed and superimposed pre- and postoperatively to compare changes in condylar volume. RESULTS: Condylar position was found to be immediately altered after surgery in the maxillary single-jaw surgery group, but at the one-year follow-up, the condyles returned to their pre-surgical position. There was no significant difference in condylar position when comparing between pre-surgery and one-year follow-up in any of the study groups. Condylar rotations in the axial and coronal planes were significant in the bimaxillary surgery group. No radiological signs of condylar bone degeneration were detected one year after the surgery. Changes in condylar volume after surgery were found to be insignificant in both study groups. CONCLUSIONS: At one year after orthognathic surgery, there were no significant changes in positional, structural, or volumetric statuses of condyles.

Comparison of Changes in the Condylar Volume and Morphology in Skeletal Class III Deformities Undergoing Orthognathic Surgery Using a Customized versus Conventional Miniplate: A Retrospective Analysis.

With the great leap in the development of three-dimensional computer-assisted surgical technology, surgeons can use a variety of assistive methods to achieve better results and evaluate surgical outcomes in detail. This retrospective study aimed to evaluate the postoperative stability after bilateral sagittal split ramus osteotomy by volume rendering methods and to evaluate how postoperative stability differs depending on the type of surgical plate. Of the patients who underwent BSSRO, ten patients in each group (non-customized miniplate and customized miniplate) who met the inclusion criteria were selected. Preoperative and postoperative cone-beam computed tomography data were collected, and condylar morphological and landmark measurements were obtained using Checkpoint and OnDemand software, respectively. The postoperative condylar morphological dataset revealed no significant difference (p > 0.05) between the two groups. No significant difference (p > 0.05) was observed between the two groups in horizontal, vertical, or angular landmark measurements used to quantify operational stability. These results indicate that there is no difference in the surgical outcome between the patient-specific system and the conventional method, which will allow clinicians to take advantage of the patient-specific system for this surgical procedure, with favorable results, as with the conventional method.

Condylar position and mandibular function after bilateral sagittal split osteotomy.

AIM: The purpose of this retrospective study was to perform an evaluation of postoperative positional changes of the condyle and mandibular function after bilateral sagittal split osteotomy (BSSO) with manual proximal segment positioning. PATIENTS: 45 patients were divided into the 2 groups ‒ G1 (advancement ‒ 14 patients) and G2 (setback - 31 patients). Rigid internal fixation screws were utilized in all cases. Inclusion criteria were only BSSO, no TMJ symptoms preoperatively and age 18 or older. RESULTS: The differences between pre- and postoperative condyle position were evaluated using measurements taken from preoperative CT scans and compared to CT scans made a minimum of 6 months postoperatively. The positional changes in both the axial and sagittal planes were measured and compared. The recovery of mandibular function was evaluated by measuring maximal interincisal opening (MIO). The results revealed that condylar positional changes after BSSO in both groups were minimal and not significantly different for all three dimensions measured. The recovery of mandibular function was faster in the group G2 than in the group G1. Mandibular function reached almost preoperative level in 6-12 months postoperatively in both groups. CONCLUSION: The results demonstrated that following BSSO, only insignificant condylar displacement and functional changes occurred within 6 to 12 months postoperatively (Tab. 4, Fig. 2, Ref. 47).