Role of Magnetic Resonance Imaging in the Clinical Diagnosis of the Temporomandibular Joint

Multi-class segmentation of temporomandibular joint using ensemble deep learning

Temporomandibular joint disorders are prevalent causes of orofacial discomfort. Diagnosis predominantly relies on assessing the configuration and positions of temporomandibular joint components in magnetic resonance images. The complex anatomy of the temporomandibular joint, coupled with the variability in magnetic resonance image quality, often hinders an accurate diagnosis. To surmount this challenge, we developed deep learning models tailored to the automatic segmentation of temporomandibular joint components, including the temporal bone, disc, and condyle. These models underwent rigorous training and validation utilizing a dataset of 3693 magnetic resonance images from 542 patients. Upon evaluation, our ensemble model, which combines five individual models, yielded average Dice similarity coefficients of 0.867, 0.733, 0.904, and 0.952 for the temporal bone, disc, condyle, and background class during internal testing. In the external validation, the average Dice similarity coefficients values for the temporal bone, disc, condyle, and background were 0.720, 0.604, 0.800, and 0.869, respectively. When applied in a clinical setting, these artificial intelligence-augmented tools enhanced the diagnostic accuracy of physicians, especially when discerning between temporomandibular joint anterior disc displacement and osteoarthritis. In essence, automated temporomandibular joint segmentation by our deep learning approach, stands as a promising aid in refining temporomandibular joint disorders diagnosis and treatment strategies.

Exploring the effect of disc displacement on the risk and severity of condylar erosion in adult temporomandibular disorder patients: A CBCT and MRI study

OBJECTIVE

The objective of the study was to investigate the relationship between types of disc displacement (DD) diagnosed by magnetic resonance imaging (MRI), and the risk (presence or absence) and severity of condylar erosion (CE) graded using cone-beam computed tomography (CBCT) in adult Temporomandibular disorders (TMD) patients.

METHODS

A total of 353 TMD patients (283 females, 70 males) underwent MRI scans to categorise DD as normal (NA), anterior displacement with reduction (ADDR), or anterior displacement without reduction (ADDNR). CE severity was graded on a scale of 0-3 (absence, mild, moderate or severe) using CBCT. To establish the plausibility and cut-off points for CE diagnosis, the severity of CE was then further divided into three classifications: Grade 0 versus 1 + 2 + 3; Grades 0 + 1 versus 2 + 3; Grades 0 + 1 + 2 versus 3. Logistic regression analysis was performed, adjusting for age, gender and joint correlation.

RESULTS

ADDNR significantly increased the risk of CE compared with NA (OR = 10.04, 95% CI: [6.41, 15.73]) and showed a significant increase in CE severity across all classifications (ORs = 10.04-18.95). The effects of ADDNR were significant in both genders (p < .001) and had a greater impact in females. ADDR was predominantly associated with mild CE.

CONCLUSIONS

ADDNR significantly increased the risk and severity of CE independent of gender when compared to NA, whereas ADDR was mainly associated with mild CE. Slight cortical discontinuity may represent a subclinical diagnosis requiring further investigation.

Quantification of temporomandibular joint space in patients with juvenile idiopathic arthritis assessed by cone beam computerized tomography

OBJECTIVE

To describe a method to calculate the total intra-articular volume (inter-osseous space) of the temporomandibular joint (TMJ) determined by cone-beam computed tomography (CBCT). This could be used as a marker of tissue proliferation and different degrees of soft tissue hyperplasia in juvenile idiopathic arthritis (JIA) patients.

MATERIALS AND METHODS

Axial single-slice CBCT images of cross-sections of the TMJs of 11 JIA patients and 11 controls were employed. From the top of the glenoid fossa, in the caudal direction, an average of 26 slices were defined in each joint (N = 44). The interosseous space was manually delimited from each slice by using dedicated software that includes a graphic interface. TMJ volumes were calculated by adding the areas measured in each slice. Two volumes were defined: Ve-i and Vi , where Ve-i is the inter-osseous space, volume defined by the borders of the fossa and Vi is the internal volume defined by the condyle. An intra-articular volume filling index (IF) was defined as Ve-i /Vi , which represents the filling of the space.

RESULTS

The measured space of the intra-articular volume, corresponding to the intra-articular soft tissue and synovial fluid, was more than twice as large in the JIA group as in the control group.

CONCLUSION

The presented method, based on CBCT, is feasible for assessing inter-osseus joint volume of the TMJ and delimits a threshold of intra-articular changes related to intra-articular soft tissue proliferation, based on differences in volumes. Intra-articular soft tissue is found to be enlarged in JIA patients.

Texture Analysis of Temporomandibular Joint Disc Changes Associated with Effusion Using Magnetic Resonance Images

The purpose of this study was to identify changes in the temporomandibular joint disc affected by effusion by using texture analysis of magnetic resonance images (MRIs).

METHODS

A total of 223 images of the TMJ, 42 with joint effusion and 181 without, were analyzed. Three consecutive slices were then exported to MaZda software, in which two oval ROIs (one in the anterior band and another in the intermediate zone of the joint disc) were determined in each slice and eleven texture parameters were calculated by using a gray-level co-occurrence matrix. Spearman's correlation coefficient test was used to assess the correlation between texture variables and to select variables for analysis. The Mann-Whitney test was used to compare the groups.

RESULTS

The significance level was set at 5%, with the results demonstrating that there was no high correlation between the parameter directions. It was possible to observe a trend between the average parameters, in which the group with effusion always had smaller values than the group without effusion, except for the parameter measuring the difference in entropy.

CONCLUSION

The trend towards lower overall values for the texture parameters suggested a different behavior between TMJ discs affected by effusion and those not affected, indicating that there may be intrinsic changes.

Jawbone measurements of edentulous sites related to implant planning using magnetic resonance imaging compared to cone beam computed tomography: An ex vivo study

AIM

To compare measurements on images obtained by magnetic resonance imaging (MRI) and cone beam CT (CBCT) for height, width, and area in alveolar bone sites in human jaw specimens.

MATERIAL AND METHODS

Forty edentulous alveolar posterior sites in human cadaver specimens were imaged using CBCT scanners, and with zero-echo-time MRI (ZTE-MRI). Semi-automatic volume registration was performed to generate representative coronal sections of the sites related to implant planning. ZTE-MRI sections were also presented after grayscale inversion (INV MRI). Three observers measured bone height, bone width 5 mm from the alveolar crest, and bone area stretching from the width measurement to the top of the alveolar crest in the images. Interobserver agreement was assessed by intra-class correlation coefficients (ICC). The measurements were analyzed using two-way repeated measures ANOVA factoring observer and image type.

RESULTS

ICC was >0.95 for bone height, width, and bone area. No significant differences among observers (p = 0.14) or image type (p = 0.60) were found for bone height. For bone width, observer (p = 0.14) was not a significant factor, while ZTE-MRI produced width estimates that were significantly different and systematically smaller than CBCT-based estimates (p ≤ 0.001). Observer (p = 0.06) was not a significant factor regarding the bone area measurements, contrary to the imaging type where ZTE-MRI led to significantly smaller area estimates than CBCT (p ≤ 0.001).

CONCLUSION

Bone height measurements were essentially equivalent using CBCT and MRI. This was found regardless of grayscale choice for the MRI. However, ZTE-MRI resulted in smaller estimates of bone width and area.

Efficacy of the transcutaneous electrostimulation in treatment dysfunctions of the TMJ associated with occlusion distortions

BACKGROUND

The study evaluation of the effectiveness the method of electrostimulation in treatment TMJ associated with occlusion disorders with the use of a patches by the company "Aganyan''.

METHODS

The study included 54 patients with temporomandibular dysfunction syndrome who had previously undergone endodontic dental treatment. In patients temporomandibular disorders (TMD) determined on the basis of Diagnostic criteria for temporomandibular disorders(DC/TMD).All patients had occlusion disorders due to errors after dental filling restoration. To diagnose the TMJ, a CT scan was used. The complex therapy also included therapy and with the use of a patches by the company "Aganyan''. The wearable patch includes a flexible substrate, a binder an adhesive layer, with an electrode foil attached to it. Patients applied one patch behind each TMJ. The patches were applied for eight hours every third day for three months. All the patients were given full-fledged endodontic treatment and restoration of the crown part, taking into account anatomical features.

RESULTS

The dynamics of the complex treatment of patients diagnosed with TMJ dysfunction syndrome showed that after treatment, the clinical symptoms gradually decreased and disappeared at the end of treatment. CT scan a year after treatment showed a normal ratio of TMJ elements. Сomplex treatment was effective in 87% of patients, after 3-5 months gradually decreased pain, noise in the joints, restriction of opening and closing of the mouth disappeared. Patients recovered their chewing functions, psycho-emotional state.

CONCLUSION

The results of the studies revealed a positive effects for the complex treatment dysfunctions syndrome TMJ the using the patches by the company "Aganyan" through electrical stimulation with low intensity.

Suppurative Temporomandibular Arthritis Caused by Chronic Suppurative Otitis Media: A Case Report

The clinical diagnosis and treatment, including information such as age, history, clinical symptoms, signs, audiology, imaging examination, mode of operation, and postoperative follow-up, of a patient with suppurative temporomandibular arthritis caused by chronic suppurative otitis media were analyzed. As conservative drug treatment and drainage surgery were ineffective, the patient was treated with microscopic open radical mastoidectomy, tympanoplasty, the plasty of the cavity of auricular concha, facial nerve decompression, coarctation of the mastoid cavity combined with otoendoscpic resection of the lower temporomandibular lesions, and standard anti-inflammatory treatment after surgery. The patient appeared to be cured at the 3-month follow-up. The ear canal was dry, without any preauricular swelling, purulent ear discharge, otalgia, limitation of mouth opening, or other symptoms. A clear diagnosis by defining the scope of the lesions, analysis of the transmission route of the lesions, and standard conservative treatment, local drainage, and surgical resection, if necessary, are recommended for patients with suppurative temporomandibular arthritis.

A Comparative Study of Temporomandibular Joints in Adults with Definite Sleep Bruxism on Magnetic Resonance Imaging and Cone-Beam Computer Tomography Images

Objective: The aim was to study the imaging characteristics of the temporomandibular joint (TMJ) of definite sleep bruxers through magnetic resonance imaging (MRI) and cone-beam computer tomography (CBCT). Methods: Nineteen definite sleep bruxers diagnosed by polysomnography and twenty asymptomatic non-bruxers matched by age, gender, and education level participated in this study. After obtaining MRI and CBCT images of all TMJs of the subjects, evaluation and measurement were conducted, respectively. The analyzed parameters included disc position, disc configuration, joint effusion (JE), joint space or condyle position, and condylar bony changes. Results: Of the 38 joints in the study group, disc deformity and disc displacement of TMJs were both 57.9% when the mouth was closed, and 76.3% showed condylar bony changes, while when the mouth was open, 82% of all TMJs showed physiological biconcave discs. Comparison of joint space revealed that the anterior space was larger in the study group. There was no significant difference between the mild and the moderate to severe sleep bruxism subgroups in the changes of TMJ. Conclusion: The results demonstrated that a higher prevalence of disc deformity, disc displacement, JE, and condylar bony changes occurred in temporomandibular joints of sleep bruxers. These changes were not related to the severity of sleep bruxism.

Correlation between the main clinical, imaging, and arthroscopy findings in patients with temporomandibular disorders

The purpose of this work was to prospectively correlate the most characteristic clinical symptoms of temporomandibular disorders, such as pain and limitation of mouth opening, with the findings of magnetic resonance imaging (disc position, degenerative changes, and effusion) and arthroscopy findings (roofing, synovitis, chondromalacia, adhesions, and perforations). These examinations were performed in 298 patients diagnosed with internal derangement refractory to conservative treatment. The mean age of the patients was 38.59 years; 92.6% were female. The t-test and one-way analysis of variance (ANOVA) were used to correlate the findings. Significant relationships were found between pain and disc displacement without reduction (P = 0.033) and effusion (P = 0.003) on MRI, coinciding with correlations between pain and roofing of 0-25% (P = 0.016) and synovitis (P = 0.001) on arthroscopy. A significant relationship was also observed between mouth opening limitation and the presence of osteoarthrosis (P = 0.018) on MRI, and between mouth opening limitation and synovitis (P = 0.022), chondromalacia (P = 0.002), and adhesions (P < 0.001) on arthroscopy. All of these findings were observed in patients with a poor initial clinical situation, which highlights the considerable potential of correlating these data with imaging and arthroscopy findings.

Potential Clinical Applications of Ozone Therapy in Dental Specialties-A Literature Review, Supported by Own Observations

Apart from conventional treatment, dentists are increasingly relying on physical therapy modalities in their clinical practice. The aim of this literature review is to analyze the clinical relevance and potential uses of ozone in modern dentistry. The research question is geared towards detailing the multiple potential applications of ozone therapy in a range of dental specialties. Based on the available literature, accessed via the PubMed, Google Scholar, Scopus, and EBSCO databases, a detailed search of the electronic literature was performed for 2001-2022. Eligible studies were chosen according to inclusion and exclusion criteria, using keywords: ozone, ozone therapy, therapeutic applications, oxidants, dental disinfectants, oral medicine, physical therapy in dentistry. Out of 834 manuscripts, 273 studies were curated. A total of 70 publications were used in the final consideration. After assessing their quality, they were analyzed to determine the relevance and potential use of ozone in the various aspects of modern dentistry. Ozone therapy is used mainly as an adjunct to the primary clinical or pharmacological treatment. In some cases of oral mucosal disease, it has proven effective as a primary therapy. During the literature analysis, it was noted that ozone therapy in dentistry is a subject of ongoing research, and the results are not always consistent. The multitude of studies in the literature on the applications of ozone in dentistry reflects the search for its undiscovered physical therapeutic potential.

Disc-condyle relationship alterations following stabilization splint therapy or arthrocentesis plus hyaluronic acid injection in patients with anterior disc displacement: a retrospective cohort study

OBJECTIVE

The objective of this study was to quantitatively evaluate the efficacy of stabilization splint (SS) therapy or arthrocentesis plus hyaluronic acid (HA) injection in the treatment of anterior disc displacement (ADD) through magnetic resonance imaging (MRI).

METHODS

99 subjects were collected in this study. 46 subjects received SS treatment (SS group), 53 subjects received arthrocentesis plus HA injection (HA group). Joints with anterior disc displacement with reduction (ADDwR) and anterior disc displacement without reduction (ADDwoR) were compared separately. MRI before the beginning of the treatment and after a set of treatment were used for measurement. Disc-condyle relationship and positions of condyles and discs were determined by disc-condyle angles and X-Y coordinates.

RESULTS

The disc-condyle angles decreased significantly in the SS group (P < .0001). Whereas no significant change was found in the HA group. Substantial anteroinferior condyle movement was detected in the SS group, slight anterior movement of condyles was discovered in the HA group. Anterior shift of discs position was observed in HA group and joints with ADDwoR in the SS group.

CONCLUSIONS

SS was effective in improving the disc-condyle relationship in ADD subjects, while significant improvement of disc-condyle relationship cannot be achieved through arthrocentesis plus HA injection.

Magnetic resonance imaging assessment of articular disc position in temporomandibular disorder subjects with various bite registrations

Objective

This study aimed to evaluate the validity and reliability of three bite registrations on articular disc position in temporomandibular disorder patients using magnetic resonance imaging (MRI).

Materials and Methods

Fifteen clinically symptomatic and orthodontically untreated temporomandibular disorder patients within the age range of 17-40 years (mean age: 28.5 years) were examined. Each patient was subjected to three bite registrations, namely maximum intercuspation, initial contact bite and Roth power centric bite, and evaluated with MRI.

Results

On the right side, the mean vertical and horizontal measurement values of the point in the most posterior aspect of the posterior band of the articular disc in relation to horizontal reference line (HRL) and vertical reference line (VRL) in the sagittal view in the Roth power centric bite were lesser (2.720 ± 1.239 mm and 2.380 ± 1.185 mm, respectively), in comparison with the other two bites, and on the left side too, it was lesser in the Roth power centric bite (2.293 ± 0.979 mm and 2.360 ± 1.078 mm, respectively), when compared to the other two bites. Statistical analysis also showed the significance of Roth power centric bite over the other two bites.

Conclusions

Favourable articular disc positional changes were observed in the Roth power centric bite followed by the initial contact bite and that maximum disc recapture was observed in most patients with the Roth power centric bite rather than in initial contact bite and maximum intercuspation positions. The Roth power centric bite could be assumed to be the ideal method for articulation and fabrication of gnathological splints for treating patients with temporomandibular disorders.

Cross-sectional and longitudinal assessment of subchondral cysts in temporomandibular joints: Clinical and MRI study with a mean follow-up of 66 months

PURPOSE

This observational study aimed to elucidate the pathophysiology of subchondral cysts (SC) in the temporomandibular joint (TMJ) and examine the results of conservative therapy administered to patients with SCs in the TMJ.

METHODS

The study included 41 patients with SCs, extracted from 684 consecutive patients who underwent magnetic resonance imaging (MRI). The anatomical features of SCs and positional abnormalities of the articular disc were initially evaluated using MRI. A second MRI examination was performed for 28/41 patients at 40-107 months (mean, 66 months) after the first MRI. The joint space, anteroposterior width of the condylar head (WiC), articular eminence angle (AEA), and visual analog scale of jaw pain (VAS) were assessed alongside the MRI examinations.

RESULTS

Most SCs were present in the anterosuperior and central condyle. Disc displacement was observed in 100% of 42 TMJs with SCs. Of the 29 joints in 28 patients, SCs in 19 joints resolved with time, whereas SCs in 10 joints persisted. A significant increase in the WiC and a significant decrease in AEA and VAS scores were observed on the second MRI scan.

CONCLUSIONS

SCs tended to form in the anterosuperior and central parts of the condyle, where mechanical loading was likely to be applied. SCs are strongly associated with articular disc displacement. Two-thirds of SCs resolved over time, accompanied by resorption and osteophytic deformation of the condyle. SC might not be an indicator for the start of surgical treatment, and nonsurgical treatment could improve the clinical symptoms of patients with SCs.

Temporomandibular joint in juvenile idiopathic arthritis: magnetic resonance imaging measurements and their correlation with imaging findings

OBJECTIVE

The aim of this study was to investigate the TMJ components in patients with juvenile idiopathic arthritis (JIA) and to compare them with a control group based on magnetic resonance imaging (MRI) measurements.

METHODS

This study comprised an assessment of MRI measurements of 96 temporomandibular joints (TMJ) following classification criteria set by the International League of Associations for Rheumatology (ILAR). Three measurements were considered for study: condyle excursion angle (CEA), height of articular eminence (HAE) and inclination of articular eminence (IAE). All TMJs were assessed by linear measurements made by using the OnDemand 3D software. The comparison between the groups was performed by using Mann-Whitney's test.

RESULTS

Lower measurement values were found for IAE, HAE and CEA in JIA patients (P-values < 0.001, 0.005 and < 0.001, respectively).

CONCLUSION

The study showed the differences in MRI measurements between JIA patients and controls, with the former with the lowest indices.

Temporal Tendinitis in Craniomandibular Dysfunction (CMD) - Does it Really Exist? A Temporomandibular MRI Investigation

OBJECTIVES

 The aim of the study was to analyze the role of temporal muscle and particularly tendon pathology in patients suffering from craniomandibular dysfunction (CMD) using magnetic resonance imaging.

MATERIALS AND METHODS

 Retrospective analysis of MRI examinations was carried out with regard to temporal muscle fibrosis and fatty degeneration and particularly temporal tendon rupture, thickening, and degenerative signal alterations. Descriptive statistics and the Mann-Whitney U-test were used for statistical evaluation.

RESULTS

 Structural lesions of temporal muscle parenchyma were the absolute exception. PD hyperintensity, pronounced contrast enhancement, or peritendinous fluid collections along the temporal tendon were found only to a small extent, and a (partial) rupture occurred in only one case. The tendon diameter showed only slight variability. The Mann-Whitney U-test provided no results indicating a causal connection between degenerative joint or disc disease and temporal tendon pathology.

CONCLUSION

 A large sample of 128 magnetic resonance imaging examinations provided no evidence of a major role of temporal tendinitis in clinical CMD syndrome.

KEY POINTS

  · Retrospective analysis of temporal tendon in CMD patients.. · Abnormal structural findings along the tendon seen only rarely.. · Obviously no crucial role of temporal tendon lesions in CMD syndrome..

CITATION FORMAT

· Stimmer H, Grill F, Waschulzik B et al. Temporal Tendinitis in Craniomandibular Dysfunction (CMD) - Does it Really Exist? A Temporomandibular MRI Investigation. Fortschr Röntgenstr 2022; DOI: 10.1055/a-1829-6134.

Functional magnetic resonance imaging evaluation of masticatory muscle dysfunction in unilateral exodontia rabbits

Objective:

Occlusal alteration due to tooth loss may cause overload of masticatory muscle and promote muscle dysfunction. This study explored the feasibility of using functional magnetic resonance imaging (fMRI) to evaluate muscle dysfunction in an established unilateral exodontia animal model.

Methods:

six rabbits were extracted right maxillary molars. T2 mapping, T2* mapping and Iterative Decomposition of water and fat with Echo Asymmetry and Least Square Estimation (IDEAL-IQ) were performed one day before extraction and every 2 weeks (2th~12th week) after extraction. The T2 and T2* values and fat fraction (FF) of bilateral temporal muscle (TM), masseter muscle (MM) and medial pterygoid muscle (MPM) were measured and compared between the extraction side-and the contralateral side. Parameters of three monitoring time points (0th, sixth, 12th week) were also analyzed.

Results:

T2 values of MM on extraction side-were significantly higher than those of contralateral side-from fourth week to 12th week after extraction (p < 0.05). T2 values of MM and MPM on extraction side-and TM on contralateral side-were significantly higher in 12th week than those in 0th week (p < 0.05). And FF of bilateral MM was significantly higher in 12th week than those in 0th week (p < 0.05). T2* value showed no significant difference between extraction side-and contralateral side-and also at above three time points.

Conclusion:

T2 and T2* value and FF can be used as indicators of masticatory muscle dysfunction. fMRI is expected to be a non-invasive method for in vivo and real-time evaluation of masticatory muscle functional abnormality.

Quality appraisal of clinical practice guidelines for temporomandibular joint disorders using the AGREE II instrument

OBJECTIVE

We sought to systematically assess the quality of all clinical practice guidelines (CPGs) describing diagnosis and management of temporomandibular joint disorders (TMDs) using the Appraisal of Guidelines for Research and Evaluation instrument.

STUDY DESIGN

CPGs detailing all aspects of diagnosis and management (both conservative and nonconservative) for TMDs were reviewed.

RESULTS

Thirteen guidelines met inclusion criteria. The highest-scoring domain across guidelines was clarity of presentation (68.3%); the lowest-scoring domain was editorial independence (31.9%). The highest-scoring guideline described traditional Korean medicine approaches to the management of TMDs, earning a mean score of 79.2% across the six quality domains. Only three CPGs met a quality threshold of >60% in at least five domains, qualifying as 'high' per the Appraisal of Guidelines for Research and Evaluation criteria: these guidelines were the Korean medicine guidelines, Research Diagnostic Criteria for Temporomandibular Disorders (RDC/TMD) guidelines for diagnostic classification of TMDs, and the Japanese Society for the Temporomandibular Joint guidelines. An average intraclass correlation coefficient of 0.79 was calculated across all domains, denoting very strong agreement between independent reviewers.

CONCLUSION

We identified a significant lack of quality in multiple areas of CPG development for the diagnosis and therapeutic management of TMDs, suggesting a need for new comprehensive and rigorously developed guidelines addressing TMDs.

Quantitative analysis of the mouth opening movement of temporomandibular joint disorder patients according to disc position using computer vision: a pilot study

BACKGROUND

Temporomandibular joint disorder (TMD), which is a broad category encompassing disc displacement, is a common condition with an increasing prevalence. This study aimed to develop an automated movement tracing algorithm for mouth opening and closing videos, and to quantitatively analyze the relationship between the results obtained using this developed system and disc position on magnetic resonance imaging (MRI).

METHODS

Mouth opening and closing videos were obtained with a digital camera from 91 subjects, who underwent MRI. Before video acquisition, an 8.0-mm-diameter circular sticker was attached to the center of the subject's upper and lower lips. The automated mouth opening tracing system based on computer vision was developed in two parts: (I) automated landmark detection of the upper and lower lips in acquired videos, and (II) graphical presentation of the tracing results for detected landmarks and an automatically calculated graph height (mouth opening length) and width (sideways values). The graph paths were divided into three types: straight, sideways-skewed, and limited-straight line graphs. All traced results were evaluated according to disc position groups determined using MRI. Graph height and width were compared between groups using analysis of variance (SPSS version 25.0; IBM Corp., Armonk, NY, USA).

RESULTS

Subjects with a normal disc position predominantly (85.72%) showed straight line graphs. The other two types (sideways-skewed or limited-straight line graphs) were found in 85.0% and 89.47% in the anterior disc displacement with reduction group and in the anterior disc displacement without reduction group, respectively, reflecting a statistically significant correlation (χ2=38.113, P<0.001). A statistically significant difference in graph height was found between the normal group and the anterior disc displacement without reduction group, 44.90±9.61 and 35.78±10.24 mm, respectively (P<0.05).

CONCLUSIONS

The developed mouth opening tracing system was reliable. It presented objective and quantitative information about different trajectories from those associated with a normal disc position in mouth opening and closing movements. This system will be helpful to clinicians when it is difficult to obtain information through MRI.

MRI and DC/TMD Methods Analyze the Diagnostic Accuracy of the Change in Articular Disc of Temporomandibular Joint

METHODS

DC/TMD clinical questionnaire diagnosis was conducted for 30 patients with temporomandibular disorder (TMD) and 11 asymptomatic volunteers who were admitted to the Department of Oral Medicine of the First Hospital affiliated with Jinan University from June 2020 to June 2021. At the same time, MRI scanned the opening and closed positions to obtain the image information of the articular disc and compared the diagnostic difference between MRI and DC/TMD to the position of the articular disc through statistical analysis.

RESULTS

The probability of DC/TMD's diagnosis of reusable/nonreusable anterior disc displacement (ADD) was 80.1% and 62.7%, respectively.

CONCLUSION

DC/TMD's diagnosis of abnormal articular disc position is less accurate than MRI testing. Therefore, the diagnosis of these two diseases for DC/TMD examination is of little significance, and MRI examination is required at the same time. It can improve diagnosis specificity and sensitivity, reduce missed diagnosis and misdiagnosis rates to ensure that true positive patients can be detected in time, and establish a basis for clinical diagnosis and treatment.

Magnetic Resonance Imaging Evaluation of Closed-Mouth TMJ Disc-Condyle Relationship in a Population of Patients Seeking for Temporomandibular Disorders Advice

Objective

To characterize the closed-mouth temporomandibular joint (TMJ) disc-condyle relationship in a population of individuals who sought hospital services for temporomandibular disorders (TMD).

Methods

Two hundred and twenty-four TMJ magnetic resonance images (MRIs) of 112 patients were assessed in all spatial planes to classify disc position with respect to the condyle in a closed-mouth position.

Results

Disc displacement (DD) was present in 62.1% and superior disc position in 29.9% of the patients. Position could not be determined in 8% of the cases. Among DD, pure anteriorized position was the most common condition (34.4%), with different combined translational and rotational displacements in all the other joints (27.7%).

Conclusion

There is a wide biological variability in disc position in closed mouth among patients seeking for TMD advice. Getting deeper into the correlation with clinical symptoms is recommended to refine the potential relevance of any diagnostic and management strategies based on the imaging evaluation of TMJ disc position.

Follow-up evaluation of temporomandibular joints using magnetic resonance imaging after mandibular trauma: Case series analysis of young adult males

BACKGROUND/AIMS

A relationship between mandibular fractures and traumatic temporomandibular joint (TMJ) conditions has been suggested in many studies. Although magnetic resonance imaging (MRI) is the best option for a TMJ evaluation, few studies have evaluated the TMJ condition after a mandibular fracture using MRI follow-up. The aim of this study was to evaluate the TMJ for post-traumatic conditions following a mandibular fracture using follow-up MRI.

MATERIALS AND METHODS

Fourteen TMJs of seven young adult males (aged 19-21 years) with mandibular fractures were analyzed by MRI, and 12 TMJs of six patients were evaluated by follow-up MRI after the trauma. Regarding the intensity of MRI, the pathologic condition of TMJ was classified into acute joint inflammation, marrow edema, and joint space widening.

RESULTS

Thirteen joints (92.9%) showed pathologic conditions, including 11 with acute joint inflammation (84.6%), 10 with joint space widening (76.9%), and six with marrow edema (46.2%). Five out of 12 evaluated joints were injected with dexamethasone. Among these, four joints healed within one week, and one healed within one month. Among the seven untreated TMJs, four and one joint healed within one week and one month, respectively, but two joints of one patient did not improve until one month. Although that patient received arthrocentesis, the right joint showed osteoarthritis six months after the trauma.

CONCLUSIONS

Most TMJs were acutely damaged due to mandibular trauma and healed within one week to one month. A follow-up examination could be considered at one month after the injury to confirm the possibility of traumatic TMJ disorder, such as osteoarthritis.

Condylar erosion is predictive of painful closed lock of the temporomandibular joint: a magnetic resonance imaging study

Background

To assess whether magnetic resonance imaging (MRI) findings of condylar erosion (CE) are predictive of a specific clinical diagnosis of painful closed lock of the temporomandibular joint (TMJ), and to determine the strength of association between CE and types of internal derangement (ID).

Methods

Based upon sample size estimation, this retrospective paired-design study involved 62 patients, aged between 18 and 67 years. Inclusion criteria were the presence of a unilateral clinical diagnosis of arthralgia coexisting with disk displacement without reduction (‘AR and DDwoR/wLO’), assigned according to the Research Diagnostic Criteria for Temporomandibular Disorders (RDC/TMD) Axis I, and the absence of signs and symptoms of TMJ pain and dysfunction on the contralateral TMJ side. Bilateral sagittal and coronal MR images were obtained to establish the prevalence of CE and TMJ ID types of disk displacement with (DDR) and without reduction (DDNR). Logistic regression analysis was used to compute odds ratios for CE and ID types. Confounding variables adjusted for were age, sex, time since pain onset, pain intensity, and type of ID.

Results

In the regression analysis, the MRI items of DDR (p = 0.533) and DDNR (p = 0.204) dropped out as nonsignificant in the diagnostic clinical ‘AR and DDwoR/wLO’ group. Significant increases in the risk of ‘AR and DDwoR’ occurred with CE (3.1:1 odds ratio; p = 0.026). The presence of CE was significantly related to DDNR (adjusted OR = 43.9; p <  0.001).

Conclusions

The data suggest CE as a dominant factor in the definition of painful closed lock of the TMJ, support the view that joint locking needs to be considered as a frequent symptom of osteoarthritis, and emphasize a strong association between the MRI items of CE and DDNR.

Osteoarthritis of the temporomandibular joint: A review of aetiology and pathogenesis

The aim of this review was to assess the level of evidence for genetic, biological, and functional predictive and predisposing factors for end-stage temporomandibular joint arthritis within the published literature. A comprehensive review based upon PRISMA guidelines was performed from all literature relevant to the topic. Case series and animal studies were included given the rare nature of the disease and goal of finding root-cause predictive factors. Clinical and radiographic measures were used specifically to identify factors which may have contributed to disease onset and progression. A total of 249 abstracts were identified based on search terms of major databases. After application of exclusion and inclusion criteria, 63 full-text articles were included in the analysis of this paper. There were few factors that could be reliably used to predict end-stage temporomandibular joint disease. Limited evidence is available to adequately predict end-stage temporomandibular joint osteoarthritis. No descriptive process exists that explains how and why this process can occur in younger adults. A better understanding of the aetiology and pathogenesis of TMJ-OA may lead to prevention and more effective management strategies that may reduce the need for drastic surgical intervention, particularly in young adults.

Morphometric Analysis of the Glenoid Fossa in the Skull Base

The aim of this study was to investigate the possible relationship between disc displacement and the presence of reduction by comparing condyle anteroposterior (AP) diameter, condyle height, mandibular fossa AP diameter, and mandibular fossa depth.

Diagnostic correlation between clinical protocols and magnetic resonance findings in temporomandibular disorders: A systematic review and meta-analysis

BACKGROUND

Our aim was to assess the diagnostic correlation between clinical protocols and magnetic resonance (MRI) findings in temporomandibular disorders (TMDs), including disc displacement with and without reduction (DDwR; DDwoR) and arthralgia.

METHODS

A systematic review performed in two phases according to the PRISMA checklist. Specific indexing terms were used for search of studies assessing TMDs through clinical diagnostic protocols with the aid of Research Diagnostic Criteria for TMDs or Diagnostic Criteria for TMDs. Quality assessment performed using QUADAS-2. Heterogeneity was assessed using I² . Publication bias was assessed using funnel plots. For meta-analysis, we used random effect model or fixed effect. The main outcomes were sensitivity and specificity of clinical protocols.

RESULTS

Fourteen studies included in the qualitative analysis and 11 studies in the meta-analysis. None of the studies fulfilled all criteria of QUADAS-2. High heterogeneity and high publication bias were found among the studies. Clinical protocols for assessing DDwR compared with MRI showed pooled sensitivity of 66% and specificity of 72%. For DDwoR, sensitivity was 61% and specificity 98%. For arthralgia, sensitivity was 43% and specificity 68% for the presence of effusion.

CONCLUSIONS

This review reveals the need for studies with improved quality. Clinical protocols show poor to moderate validity in diagnosis of DDwR and DDwoR compared with MRI. No correlation was found between a clinical diagnosis of arthralgia and MRI effusion. Clinical diagnostic protocols can be used as screening tools, reserving the use of MRI for a more accurate diagnosis in patients with symptoms or dysfunction.

Management of Septic Arthritis of the Temporomandibular Joint in Dogs

Septic arthritis of the temporomandibular joint (TMJ) in dogs and other mammals is a rare condition. It is typically associated with notable pain, swelling, and difficulty in opening the mouth. Unlike degenerative TMJ disease, septic arthritis requires urgent intervention. The etiology of the condition may include penetrating trauma, an extension of local infection, such as otitis media, or the hematogenous spread of a pathogen. However, the precise cause may not always be identified. Diagnostic imaging with Computed Tomography (CT), cone-beam CT (CBCT), and/or Magnetic Resonance Imaging (MRI) are helpful for honing the definitive diagnosis and formulating a treatment plan. Subsequently, exploratory surgery may be required to obtain samples for culture and sensitivity and histology and to lavage the joint. In this “methods” article, we provide a detailed description of our approach to diagnosis and management of septic TMJ arthritis in four dogs.

Relationship between rotational disc displacement of the temporomandibular joint and the dentoskeletal morphology

Objective

The purpose of this study was to evaluate the relationship between rotational disk displacement (DD) of the temporomandibular joint (TMJ) and the dentoskeletal morphology.

Methods

Women aged > 17 years were included in this study. Each subject had a primary complaint of malocclusion and underwent routine cephalometric examinations. They were divided into five groups according to the findings on sagittal and coronal magnetic resonance images of their TMJs bilateral normal disk position, bilateral anterior DD with reduction (ADDR), bilateral rotational DD with reduction (RDDR), bilateral anterior DD without reduction (ADDNR), and bilateral rotational DD without reduction (RDDNR). Twenty-three cephalometric variables were analyzed, and the Kruskal–Wallis test was used to evaluate differences in the dentoskeletal morphology among the five groups.

Results

Patients with TMJ DD exhibited a hyperdivergent pattern with a retrognathic mandible, unlike those with a normal disk position. These specific skeletal characteristics were more severe in patients exhibiting DD without reduction than in those with reduction, regardless of the presence of rotational DD. Rotational DD significantly influenced horizontal and vertical skeletal patterns only in the stage of DD with reduction, and the mandible exhibited a more backward position and rotation in patients with RDDR than in those with ADDR. However, there were no significant dentoskeletal differences between ADDNR and RDDNR.

Conclusions

The results of this study suggest that rotational DD of TMJ plays an important role in the dentoskeletal morphology, particularly in patients showing DD with reduction.

Design of an Intraoral Dipole Antenna for Dental Applications

OBJECTIVE

In dental MRI, intraoral coils provide higher signal-to-noise ratio (SNR) than coils placed outside the mouth. This study aims to design an intraoral dipole antenna and demonstrates the feasibility of combining it with an extraoral coil.

METHODS

Dipole antenna design was chosen over loop design, as it is open toward the distal; therefore, it does not restrain tongue movement. The dipole design offers also an increased depth-of-sensitivity that allows for MRI of dental roots. Different dipole antenna designs were simulated using a finite-difference-time-domain approach. Ribbon, wire, and multi-wire arms were compared. The best design was improved further by covering the ends of the dipole arms with a high-permittivity material. Phantom and in vivo measurements were conducted on a 3T clinical MRI system.

RESULTS

The best transmit efficiency and homogeneity was achieved with a multi-wire curved dipole antenna with 7 wires for each arm. With an additional high-permittivity cap the transmit field inhomogeneity was further reduced from 20% to 5% along the dipole arm. When combined with extraoral flexible surface-coil, the coupling between the coils was less than -32dB and SNR was increased.

CONCLUSION

Using intraoral dipole design instead of loop improves patient comfort. We demonstrated feasibility of the intraoral dipole combined with an extraoral flexible coil-array for dental MRI. Dipole antenna enabled decreasing imaging field-of-view, and reduced the prevalent signal from tongue.

SIGNIFICANCE

This study highlights the advantages and the main challenges of the intraoral RF coils and describes a novel RF coil that addresses those challenges.

Orthodontic appliances and MR image artefacts: An exploratory in vitro and in vivo study using 1.5-T and 3-T scanners

Purpose

The aim of this study was to assess the artefacts of 12 fixed orthodontic appliances in magnetic resonance images obtained using 1.5-T and 3-T scanners, and to evaluate different imaging sequences designed to suppress metal artefacts.

Materials and Methods

In vitro, study casts of 1 adult with normal occlusion were used. Twelve orthodontic appliances were attached to the study casts and scanned. Turbo spin echo (TSE), TSE with high readout bandwidth, and TSE with view angle tilting and slice encoding for metal artefact correction were used to suppress metal artefacts. Artefacts were measured. In vivo, 6 appliances were scanned: 1) conventional stainless-steel brackets; 2) nickel-free brackets; 3) titanium brackets; 4) a Herbst appliance; 5) a fixed retainer; and 6) a rapid maxillary expander. The maxilla, mandible, nasopharynx, tongue, temporomandibular joints, and cranial base/eye globes were assessed. Scores of 0, 1, 2, and 3 indicated no artefacts and minor, moderate, and major artefacts, respectively.

Results

In vitro, titanium brackets and the fixed retainer created minor artefacts. In vivo, titanium brackets caused minor artefacts. Conventional stainless-steel and nickel free brackets, the fixed retainer, and the rapid maxillary expander caused major artefacts in the maxilla and mandible. Conventional stainless-steel and nickel-free brackets caused major artefacts in the eye globe (3-T). TSE with high readout bandwidth reduced image artefacts in both scanners.

Conclusion

Titanium brackets, the Herbst appliance, and the fixed retainer caused minor artefacts in images of neurocranial structures (1.5-T and 3-T) when using TSE with high readout bandwidth.

Relative risk of positional and dynamic temporomandibular disc abnormality for osteoarthritis-magnetic resonance imaging study

Dynamic articular disc abnormality (wR, with reduction; woR, without reduction) is well known as the risk factor for temporomandibular joint osteoarthritis (TMJOA). However, there are few speculations on the potential risk of positional disc abnormalities for TMJOA. The purpose of this study was to investigate the relative risk of positional abnormality and dynamic abnormality of the temporomandibular disc for OA after the three-dimensional interpretation of all the sagittal and coronal planes of magnetic resonance (MR) data in a large dataset of consecutive subjects. Experimental samples consisted of images of 1356 TMJs of patients. A diagnosis of disc state was established in each TMJ utilising a 1.5T MR imaging scanner. A binary logistic regression analysis was performed to identify the significant associations between the outcome (dependent variable: the presence of OA) and the predictors (covariates: age, sex, dynamic disc state [the presence of woR], and 5 categories of the positional disc state [NA, no abnormality; SW, sideways; pADD, partial anterior; cADD, complete anterior; PDD, posterior]). Based on the result of the binary logistic regression analysis, the presence of woR showed an odds ratio of 14.1 (P < .05). In addition, compared with the joints NA, those with SW and cADD showed odds ratios of 5.62 and 10.88, respectively (P < .05). Despite the limitations of the study, in the positional disc abnormalities, sideways disc displacement and complete anterior disc displacement could be associated with the occurrence of TMJOA. All the coronal and sagittal MR images should be evaluated to assess intra-articular joint disorders accurately.

Infectious arthritis and the temporomandibular joint. A review

OBJECTIVE

Microorganisms can cause acute infectious arthritis, chronic infectious arthritis, or reactive inflammatory arthritis. The aim of this study is to perform a narrative review of the pathophysiology, etiology, and diagnostic features of infectious arthritis and TMJ infectious arthritis.

METHODS

A search of the literature was performed using Medline, Scielo, Embase, and Google Scholar databases. The terms employed for the search were "Temporomandibular Joint Disorders" and "Infectious Arthritis"; or "Septic Arthritis"; or "Bacterial, Fungal, or Viral Arthritis." Over three hundred articles were screened for eligibility.

RESULTS

The selected articles were utilized to perform a narrative review of the general aspects of infectious arthritis and infectious arthritis affecting the TMJ.

CONCLUSION

Infectious arthritis is a rare, yet very morbid, form of arthritis. Understanding general aspects of joint infections and specific features of TMJ infectious arthritis is imperative for an adequate diagnosis.

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.

Management of temporomandibular joint disorders: A surgeon's perspective

Disorders of the Temporomandibular joint (TMJ) may clinically present with jaw pain and restricted mouth opening that may limit a patient's access to comprehensive dental care. The aim of this article is to provide a general overview of the current treatment strategies available in the management of disorders of the TMJ. Both conservative and surgical treatment options will be discussed as there is no one treatment for temporomandibular disorders (TMD) which encompasses a wide range of diagnoses. A multidisciplinary team approach to management is essential in the fundamental care of all TMD patients so that treatment can be specifically tailored to individual patient needs.

Evaluation of the efficacy of different treatment modalities for painful temporomandibular disorders

The purpose of this study was to clinically evaluate the efficacies of three treatment methods and to compare their outcomes in patients with painful disc displacement. The study group comprised 45 patients with unilateral temporomandibular disorders who fell into Axis I group II (with limited mouth opening) of the Research Diagnostic Criteria for Temporomandibular Disorders. Magnetic resonance imaging was used for definitive diagnosis. The patients were divided randomly into three groups according to the treatment method: splint therapy, splint therapy with ultrasound-guided arthrocentesis, and splint therapy with low-level laser therapy. Patients were followed up after treatment for 6 months. The groups were compared in terms of pain and functional jaw movements (unassisted mouth opening without pain, maximum unassisted mouth opening, and contralateral movements). At the end of treatment, functional jaw movements were significantly increased while pain values were significantly decreased in all groups (P<0.05). Group 2 had a quicker improvement in terms of mouth opening scores at the end of the first month, and unassisted mouth opening without pain was found to be more than 35 millimetres in all groups at the end of 6 months. All treatment modalities showed effective results on pain and functional jaw movements in the treatment of temporomandibular disorders.

In vivo prediction of temporomandibular joint disc thickness and position changes for different jaw positions

Temporomandibular joint disorders (TMD) are common dysfunctions of the masticatory region and are often linked to dislocation or changes of the temporomandibular joint (TMJ) disc. Magnetic resonance imaging (MRI) is the gold standard for TMJ imaging but standard clinical sequences do not deliver a sufficient resolution and contrast for the creation of detailed meshes of the TMJ disc. Additionally, bony structures cannot be captured appropriately using standard MRI sequences due to their low signal intensity. The objective of this study was to enable researchers to create high resolution representations of all structures of the TMJ and consequently investigate morphological as well as positional changes of the masticatory system. To create meshes of the bony structures, a single computed tomography (CT) scan was acquired. In addition, a high-resolution MRI sequence was produced, which is used to collect the thickness and position change of the disc for various static postures using bite blocks. Changes in thickness of the TMJ disc as well as disc translation were measured. The newly developed workflow successfully allows researchers to create high resolution models of all structures of the TMJ for various static positions, enabling the investigation of TMJ disc translation and deformation. Discs were thinnest in the lateral part and moved mainly anteriorly and slightly medially. The procedure offers the most comprehensive picture of disc positioning and thickness changes reported to date. The presented data can be used for the development of a biomechanical computer model of TMJ anatomy and to investigate dynamic and static loads on the components of the system, which could be useful for the prediction of TMD onset.

Correlation of magnetic resonance imaging grades with cytokine levels of synovial fluid of patients with temporomandibular joint disorders: a cross-sectional study

OBJECTIVES

Magnetic resonance imaging (MRI) is a standardized method for assisting joint diagnosis. To validate the reliability of different imaging-based grading systems, this study examined (1) the associations between grading systems for osseous change, joint effusion, and the Wilkes classification of temporomandibular joint (TMJ) disorders and (2) the correlation between cytokines in synovial fluid and imaging-based joint scores.

MATERIALS AND METHODS

Twenty-seven patients, who routinely received numeric rating scale (NRS) and MRI assessment before TMJ arthrocentesis, were enrolled. Each joint was evaluated through the grading criteria for severity of osseous change and joint effusion by blinded observers using MRI. ImageJ was employed for classifying joint effusion. Joint synovial fluid, collected through arthrocentesis, was examined for cytokine expression by using a Luminex multiplex assay. All data were analyzed using the Pearson correlation analysis.

RESULTS

The Wilkes classification was strongly correlated with osseous change scores, but not with joint effusion scores. Joint effusion scores significantly correlated with NRS scores, but not with the Wilkes classification and osseous change scores. Compared with osseous change scores, joint effusion scores had a higher correlation with the levels of inflammatory cytokines (interleukin (IL)-8 and soluble IL-6 receptor (sIL-6R)) and with anti-inflammatory cytokines (soluble tumor necrosis factor receptors I and II (sTNF-RI/II)).

CONCLUSIONS

In patients with TMJ disorders, MRI grades are strongly correlated with NRS scores and levels of cytokines (IL-8, sIL-6R, and sTNF-RI/II) in the synovial fluid.

CLINICAL RELEVANCE

Joint effusion scoring can be a reliable and valid indicator for pathological assessment of TMJ disorders.

Temporomandibular joint anterior disc displacement with reduction in a young population: Prevalence and risk indicators

BACKGROUND

Temporomandibular joint (TMJ) anterior disc displacements with reduction (ADDR) are commonly found in the young population and often found to be associated with biomechanical and anatomical factors. Until now, most knowledge on ADDR among children and adolescents comes from studies performed on Caucasian subjects.

AIMS

To assess the clinically determined prevalence rates of ADDR among the young Indonesian population and to evaluate its risk indicators.

DESIGN

In this cross-sectional study, 1562 pupils and students of 7-21 years old completed a questionnaire and underwent a clinical examination.

RESULTS

The prevalence rates of ADDR were 7.0% among children (7-12 years), 14.4% among adolescents (13-18 years), and 12.3% among young adults (19-21 years). Logistic regression analyses revealed that increasing age and lip biting were associated with ADDR in children, whereas pen biting was associated with ADDR in the adolescent population. None of the included factors were found to be associated with ADDR in the young adult population.

CONCLUSIONS

The present findings indicate that prevalence of ADDR increases with age, with a peak during the years of adolescence. Biomechanical factors seem to play a significant role in ADDR development.

Subjective analysis of the application of enhancement filters on magnetic resonance imaging of the temporomandibular joint

OBJECTIVE

The aim of this study was to investigate the effect of enhancement filters on magnetic resonance imaging (MRI) of the temporomandibular joint (TMJ).

STUDY DESIGN

In total, 66 MRI scans of the TMJ were analyzed without filtration and with the application of 2 filters: Sharpen 1 and Sharpen 2 (OnDemand software). Two dentomaxillofacial radiologists examined the original and filtered images individually. Intra- and interobserver concordance was measured by using generalized estimating equations. The observers evaluated the subjective image quality and the visibility of 3 components of the TMJ: disk, condyle, and articular eminence. The images were ranked on a 4-point scale, from poor to excellent. The image quality of all filtered images was compared by using the χ² test and Bonferroni correction for multiple comparisons.

RESULTS

Intra- and interobserver concordance was good. The images filtered with Sharpen 1 and Sharpen 2 provided better definition of the structures compared with nonfiltered images, providing the highest scores for subjective image quality for all structures (P < .0001).

CONCLUSIONS

The use of enhancement filters led to improved subjective quality and may improve the diagnostic efficacy of MRI in TMJ evaluation.

Inclination of the condylar long axis is not related to temporomandibular disc displacement

AIM

The aim of the present study was to correlate the angle formed by inclination of the condylar long axis and median sagittal plane to the presence of internal disc derangement, as well as changes in eccentric mandibular positions.

METHODS

The sample consisted of magnetic resonance images of 35 temporomandibular joint (TMJ) acquired with a 1.5T magnetic resonance imaging system with surface coils of 8.5 cm in diameter. Parasagittal images were used according to the following parameters: TMJ disc position with mouth closed, TMJ disc position with mouth open, TMJ disc function, and degrees of rotation and translation of the condyle. Next, we determined the angles between the condyle long axis and median sagittal plane by using axial images.

RESULTS

The results showed correlations between TMJ disc position and disc function (P = 0.009), as well as between disc position and degree of condylar rotation (P = 0.008). The main purpose of the present study was to assess the angle of the condylar long axis, with no statistical correlation being found between this variable and disc position (P = 0.787), disc function (P = 0.091), condylar translation (P = 0.808), and condylar rotation (P = 0.115).

CONCLUSION

There was no relationship between inclination of the condyle long axis and parameters of internal derangements.

Temporomandibular Joint Internal Derangement Score (TIDS): novel magnetic resonance imaging assessment score and its relation to invasive treatment in patients with clinical temporomandibular joint pathology

Purpose

A new magnetic resonance imaging (MRI) based scoring system for temporomandibular joint (TMJ) internal derangement was developed to predict disease severity and the likelihood of invasive treatment.

Patients and methods

Reports and images from bilateral TMJ MRI studies of 100 consecutive patients with TMJ pain were retrospectively reviewed. A Temporomandibular Joint Internal Derangement Score (TIDS) score was composed of 6 MRI characteristics: joint effusion, disc displacement, disc nonrecapture, disc degenerative changes, abnormal condyle translation, and condyle arthritis. The primary endpoint was whether disease severity merited invasive treatment (arthrocentesis, arthroscopy, arthroplasty, or discectomy). Primary analyses were conducted as univariate regression, with the level of significance set at p < .05. Multivariate regression was also used to assess the impacts of each variable upon the need for invasive treatment.

Results

Invasive treatment was performed in 29 patients and planned in an additional 9 patients. Patients with clinical bilateral pathology were no more likely to undergo invasive treatment than those with unilateral clinical pathology. Statistically significant correlations were found between bilateral invasive treatment and the presence of bilateral joint effusions (p = 0.0037) and disc displacement (p = 0.014), as well as with increasing values of right TIDS (p = 0.0015) and bilateral TIDS (p = 0.0090). Bilateral TIDS of greater than 6 was correlated with both bilateral invasive treatment (p = 0.0033) and with invasive treatment of any kind (p = 0.041). In each instance of TIDS > 6, the patient demonstrated multiple signs of bilateral TMJ pathology. On multivariate regression, only disc recapture failed to trend towards statistical significance in both the six and twelve component regressions, which trended towards significance only in the twelve component analysis.

Conclusion

A TIDS score was developed to serve as an adjunct to the clinical assessment of TMJ pathology. Bilateral TIDS score greater than 6 was statistically significantly correlated with the severity of TMJ pathology.

A Prognostic Nomogram for Postoperative Bone Remodeling in Patients with ADDWoR

This study aimed to establish an effective prognostic nomogram for predicting the probability of postoperative bone remodeling of patients with anterior disc displacement without reduction (ADDWoR). The nomogram was based on a retrospective study on patients underwent surgical approaches for ADDWoR at Shanghai Ninth People’s Hospital, Shanghai Jiao Tong University from January, 2007 to January, 2017. A multivariate logistic regression analysis was used to develop variables suitable for probability estimation model. The predictive accuracy and discriminative ability were determined by ROC (AUC-index) and calibration curve. Results were validated using bootstrap resampling with all statistical tests two-sided. 1110 patients were included in the analysis. The probability of postoperative bone remodeling in ADDWoR was 0.51. Six independent prognostic factors including age of onset, nocturnal bruxism, disc morphology, BMD, Wilkes’ classification, and postoperative splint therapy were integrated to construct the nomogram. The probability estimation model showed good discrimination in both internal and external validation with AUC-index of 0.84. The calibration curves for probability of postoperative bone remodeling showed optimal agreement with actual observation. In conclusion, a nomogram was established to provide individual prediction of postoperative bone remodeling for patients with ADDWoR treated by arthroscopy surgery.

Pain Management Associated with Posttraumatic Unilateral Temporomandibular Joint Anterior Disc Displacement: A Case Report and Literature Review

The aim of the present article is to review the etiological risk factors and the general and oral management of anterior disc displacement with reduction caused by a chin trauma, and to describe the diagnostic process and the treatment provided to an affected 7-year-old girl. The patient also experienced frequent and severe cephaleas, which may be related to cervical vertebrae deviation. The patient was successfully treated with an intraoral occlusal splint and analgesics. Pediatric dentists must always be aware of the early signs and symptoms of temporomandibular joint disorders in their patients, especially in cases of orofacial trauma history, with the aim of providing an opportune resolution and preventing its progression later in life. Occlusal splints are strongly recommended for the treatment of anterior disc displacement with reduction in children and adolescents.

Clinical implications of magnetic resonance imaging in temporomandibular disorders patients presenting ear fullness

OBJECTIVES/HYPOTHESIS

The aim of this study was to investigate whether findings detected by temporomandibular joint magnetic resonance imaging (TMJ-MRI) can provide pathognomonic evidence of temporomandibular disorders (TMD) in patients with nonspecific ear fullness (EF). The association of nonspecific EF with clinical characteristics of TMD based on TMJ-MRI findings was examined.

STUDY DESIGN

Retrospective analysis.

METHODS

Thirty-four subjects (42 ears) who had no detectable otologic problems as a cause of EF were enrolled in this study. Each subject underwent TMJ-MRI to identify pathology of the TMJ as a possible cause of nonspecific EF. All subjects participated in the re-evaluation process following TMD treatment.

RESULTS

Anatomical abnormalities in TMJ-MRI, irrespective of TMD signs, were observed in 34 of the 42 ears (80.9%), such as degenerative change of the TMJ (16 ears), articular disc displacement (11 ears), and joint effusion (seven ears). Specific abnormalities of the TMJ were associated with nonspecific EF, and this symptom showed improvement following individualized TMD treatment in those with internal derangement and/or effusion of the TMJ. However, abnormal TMJ-MRI findings were also observed in seven of nine ears with no TMD signs, and there was no significant association between the presence of TMD signs and abnormal TMJ-MRI findings (χ² = 0.075, P = .784).

CONCLUSIONS

Patients presenting with nonspecific EF may have TMD, which can be effectively diagnosed using TMJ-MRI. The present study revealed the causal relationship between nonspecific EF and abnormal TMJ findings based on MRI. Individualized TMD treatments based on TMJ-MRI led to improved treatment outcomes with special regard to nonspecific EF LEVEL OF EVIDENCE: 4. Laryngoscope, 128:1692-1698, 2018.