Magnetic resonance imaging of temporomandibular joint dysfunction-correlation with clinical symptoms, age, and gender

Comparison of disc position stability and condylar bone remodeling between two open disc repositioning surgeries: a retrospective single-center cohort study

BACKGROUND AND OBJECTIVE

Open suturing (OSu) and Mini-screw Anchor (MsA) are two commonly used open disc repositioning surgeries for anterior disc displacement (ADD) of the temporomandibular joint (TMJ). This study assesses the differences in disc position stability (DPS) and condylar bone remodeling (CBR) between these two surgical procedures in a single center.

METHODS

A retrospective cohort study using magnetic resonance imaging (MRI) scans (preoperation, 1 week and 12 mo postoperation) of all patients who had open TMJ disc repositioning surgery from January 2016 to June 2021 at one center through two surgical techniques (OSu and MsA) was performed. The predictor variable was technique (OSu and MsA). Outcome variables were DPS and CBR. During follow-up, DPS was rated as good, acceptable and poor, and CBR was graded as improved, unchanged, and degenerated. Multivariate analysis was used to compare the DPS and CBR at 12 months after adjusting 5 factors including age, sex, Wilkes stage, preoperative bone status (normal, mild/moderate abnormal) and the degree of disc repositioning (normal, overcorrected, and posteriorly repositioned). Relative risk (RR) for DPS and CBR was calculated by multivariate logistic regression.

RESULTS

385 patients with 583 joints were included in the study. MRIs at 12 months showed that 514 joints (93.5%) had good DPS, and 344 joints (62.5%) had improved CBR. Multivariate analysis revealed that OSu had higher DPS (RR=2.95; 95% confidence interval [CI], 1.27 to 6.85) and better CBR (RR=1.58; 95%CI, 1.02 to 2.46) than MsA. Among the factors affecting DPS, females had better results than males (RR=2.63; 95%CI, 1.11 to 6.26) and overcorrected or posteriorly repositioned discs were more stable than normally-repositioned discs (RR=5.84; 95%CI, 2.58 to 13.20). The improvement in CBR decreased with age increasing (RR=0.91; 95%CI, 0.89 to 0.93). Preoperative mild/moderate abnormal bone status had a higher probability of improved CBR compared to normal preoperative bone status (RR=2.60; 95%CI, 1.76 to 3.83).

CONCLUSION

OSu had better DPS and CBR than MsA. Sex and the degree of disc repositioning impacted DPS, while age and preoperative bone status affected CBR.

Is magnetic resonance imaging or cone beam computed tomography alone adequate for the radiological diagnosis of symptomatic temporomandibular joint osteoarthritis? A retrospective study

This study was performed to compare the diagnostic accuracy of cone beam computed tomography (CBCT) alone and magnetic resonance imaging (MRI) alone in patients with clinical symptoms of temporomandibular joint osteoarthritis (TMJ-OA). Fifty-two patients (83 joints) with clinical signs of TMJ-OA were included in the study. Two examiners evaluated CBCT and MRI images. McNemar and kappa tests and Spearman's correlation analysis were applied. Radiological findings of TMJ-OA were detected in all 83 joints on CBCT or MRI . Seventy-four joints (89.2%) were positive for degenerative osseous changes on CBCT. MRI findings were positive in 50 joints (60.2%). Osseous changes were found in 22 joints, joint effusion in 30 joints, and disc perforation/degeneration in 11 joints on MRI. CBCT was more sensitive than MRI in detecting condylar erosion (P = 0.001), osteophyte (P = 0.001), and flattening (P = 0.002) and flattening of the articular eminence (P = 0.013) . Poor agreement (κ = -0.21) and weak correlations were found between CBCT and MRI. The study findings suggest that CBCT is superior to MRI in evaluating osseous changes of TMJ-OA, and that CBCT is more sensitive than MRI in detecting condylar erosion, condylar osteophyte, and flattening of the condyle and articular eminence.

Artificial intelligence for detecting temporomandibular joint osteoarthritis using radiographic image data: A systematic review and meta-analysis of diagnostic test accuracy

In this review, we assessed the diagnostic efficiency of artificial intelligence (AI) models in detecting temporomandibular joint osteoarthritis (TMJOA) using radiographic imaging data. Based upon the PRISMA guidelines, a systematic review of studies published between January 2010 and January 2023 was conducted using PubMed, Web of Science, Scopus, and Embase. Articles on the accuracy of AI to detect TMJOA or degenerative changes by radiographic imaging were selected. The characteristics and diagnostic information of each article were extracted. The quality of studies was assessed by the QUADAS-2 tool. Pooled data for sensitivity, specificity, and summary receiver operating characteristic curve (SROC) were calculated. Of 513 records identified through a database search, six met the inclusion criteria and were collected. The pooled sensitivity, specificity, and area under the curve (AUC) were 80%, 90%, and 92%, respectively. Substantial heterogeneity between AI models mainly arose from imaging modality, ethnicity, sex, techniques of AI, and sample size. This article confirmed AI models have enormous potential for diagnosing TMJOA automatically through radiographic imaging. Therefore, AI models appear to have enormous potential to diagnose TMJOA automatically using radiographic images. However, further studies are needed to evaluate AI more thoroughly.

Prevalence of Clinical Signs and Symptoms of Temporomandibular Joint Disorders Registered in the EUROTMJ Database: A Prospective Study in a Portuguese Center

Temporomandibular joint disorders (TMDs) are characterized by their multifactorial etiology and pathogenesis. A 3-year prospective study was conducted in a Portuguese TMDs department to study the prevalence of different TMDs signs and symptoms and their association with risk factors and comorbidities. Five hundred ninety-five patients were included using an online database: EUROTMJ. Most patients were female (80.50%), with a mean age of 38.20 ± 15.73 years. The main complaints were: (1) temporomandibular joint (TMJ) clicking (13.26%); (2) TMJ pain (12.49%); (3) masticatory muscle tension (12.15%). The main clinical findings were myalgia (74%), TMJ clicking (60-62%), and TMJ arthralgia (31-36%). Risk factors such as clenching (60%) and bruxism (30%) were positively associated with TMJ pain and myalgia. Orthodontic treatment (20%) and wisdom tooth removal (19%) were positively associated with TMJ clicking, while jaw trauma (6%), tracheal intubation (4%) and orthognathic surgery (1%) were positively associated with TMJ crepitus, limited mandibular range of motion, and TMJ pain, respectively. In total, 42.88% of TMDs patients had other associated chronic diseases, most of them were mental behavioral or neurodevelopmental disorders (33.76%), namely, anxiety (20%) and depression (13%). The authors also observed a positive association of mental disorders with the degree of TMJ pain and myalgia. The online database seems to be a relevant scientific instrument for healthcare providers who treat TMDs. The authors expect that the EUROTMJ database can serve as a milestone for other TMDs departments.

MRI changes and clinical characteristics in temporomandibular joints with displacement of the articular disk without reduction - a cross-sectional observational study

OBJECTIVES

This study examined changes in magnetic resonance imaging (MRI) of temporomandibular joints (TMJ) with anterior displacement disk without reduction (DDwoR) and its correlation to clinical symptoms.

METHODS

190 individuals with DDwoR were evaluated according to Diagnostic Criteria for Temporomandibular Disorders (DC/TMD) and MRI. Pain's chronicity/intensity and limited mouth opening (locking) were correlated with: TMJ degeneration (MRI T1), effusion (T2), disc's shape and position (proton density).

RESULTS

In 103 TMJ with DDwoR, hemiconvex shape (41.6%), sclerosis (45.6%) and mild effusion (47.6%) were the most prevalent findings. There was not association (p > .05) between: different DDwoR positions with pain's intensity/chronicity; effusion with locking. Disk deformation was associated with degeneration (p = .034) and pain's intensity (p = .006). Locking was associated with degeneration (p = .05).

CONCLUSIONS

Condylar osteodegeneration is often related to DDwoR. Locking by DDwoR is associated with severe levels of chronic pain and articular disk deformation.

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.

Understanding Early-Stage Posttraumatic Osteoarthritis for Future Prospects of Diagnosis: from Knee to Temporomandibular Joint

PURPOSE OF REVIEW

Many mechanical load-bearing joints of the body are prone to posttraumatic osteoarthritis (PTOA), including the knee joint and temporomandibular joint (TMJ). Early detection of PTOA can be beneficial in prevention or alleviating further progression of the disease.

RECENT FINDINGS

Various mouse models, similar to those used in development of novel diagnosis strategies for early stages of OA, have been proposed to study early PTOA. While many studies have focused on OA and PTOA in the knee joint, early diagnostic methods for OA and PTOA of the TMJ are still not well established. Previously, we showed that fluorescent near-infrared imaging can diagnose inflammation and cartilage damage in mouse models of knee PTOA. Here we propose that the same approach can be used for early diagnosis of TMJ-PTOA. In this review, we present a brief overview of PTOA, application of relevant mouse models, current imaging methods available to examine TMJ-PTOA, and the prospects of near-infrared optical imaging to diagnose early-stage TMJ-OA.

MRI characteristics of the asymptomatic temporomandibular joint in patients with unilateral temporomandibular joint disorder

OBJECTIVE

To determine the association between unilateral temporomandibular joint disorder (TMD) and the presence of imaging abnormalities in the contralateral, asymptomatic joint.

METHODS

MRI studies of 219 subjects with symptoms of unilateral TMD were examined for signs of disc displacement, osteoarthritis, disc deformation, and effusion in both temporomandibular joints (TMJ). The Chi-Square test and stepwise logistic regression analysis were performed.

RESULTS

Disc displacement, osteoarthritis, disc deformation, and effusion were more common on the symptomatic side. However, in the category of disc displacement with a reduction in open mouth position (DDWR), the difference was not significant between the symptomatic and the asymptomatic TMJs. Stepwise logistic regression showed that the presence of any imaging abnormality other than DDWR was related to osteoarthritis and disc deformity on the symptomatic side. On the other hand, the presence of any MRI abnormality (including DDWR) on the asymptomatic side was related only to the presence of osteoarthritis on the symptomatic side.

CONCLUSIONS

Unilateral symptomatic TMD is related to the presence of imaging abnormalities on the contralateral, asymptomatic side, suggesting that the development and progression of joint changes in symptomatic and contralateral asymptomatic TMJs are interrelated.

The epidemiology, nature, and impact of eating and swallowing problems in adults presenting with temporomandibular disorders

OBJECTIVE

Temporomandibular disorders (TMDs) are the most common non-dental orofacial pain disorders. Research suggests that patients with TMDs experience eating and swallowing problems, although information is sparse, impacting effectiveness of management. Research aims were to investigate the epidemiology and impact of TMD-related eating and swallowing problems.

METHODS

A cross-sectional study was completed in two national Irish specialist centers, with 126 participants with TMDs assessed using a specifically-devised protocol. Descriptive and statistical analyses were completed.

RESULTS

Masticatory issues (95%), swallowing difficulties (53%), and weight loss (50%) were prevalent. Participants reported moderately severe eating and swallowing problems impacting participation and well-being across daily and social activities.

DISCUSSION

A variety of eating and swallowing problems are reported by adults with TMDs, which impact functioning and psychosocial well-being. The need to improve clinical practice and research is argued. Future research should refine the original assessment protocol developed in this study.

[Morphometric features of the temporomandibular joints according to MR studies in adult patients with dislocations of the articular discs and malocclusion of the anterior teeth]

THE PURPOSE OF THE STUDY

To study the morphological features of the temporomandibular joints (TMJ) according to MR studies in adult patients with impaired occlusion of the anterior teeth and dislocations of the articular discs.

MATERIAL AND METHODS

The clinical study included 51 patients aged 17 to 47 years (mean age 28.12±7.44 years): 14 men and 37 women. On the basis of a clinical examination and MR findings of TMJ in 30 patients (mean age 26.77±7.48 years; 8 men and 22 women), TMJ dysfunction in the form of dislocation of articular discs was confirmed. In 21 patients (mean age 30.05±7.12; 15 women, 6 men), TMJ dysfunction without dislocation of articular discs was confirmed. The patients measured the value of vertical incisive overlap (overbite). Analyzing data from MR studies of TMJ, we measured the following values of both TMJs of each patient: the depth and transverse size of the articular fossa, the height of the articular tubercles and the transverse size of the head of the lower jaw.

RESULTS

The examined patients with joint dislocations of TMJ had morphological features: statistically significantly deeper and narrower articular fossae, higher articular tubercles and narrower in the sagittal plane of the head of the lower jaw compared to TMJ of patients with dysfunction without dislocation of articular disks. In addition, in patients with articular disk dislocations, a statistically significant (<0.05) increase in vertical incisal overlap was noted.

CONCLUSION

.TMJ in patients with dysfunction in the form of dislocations of articular discs had morphological features that allowed them to be classified as type 3.

Prevalence of temporomandibular disorder pain, jaw noises and oral behaviours in an adult Italian population sample

To evaluate the prevalence of temporomandibular disorder pain (TMD-pain), temporomandibular joint (TMJ) noises, oral behaviours in an Italian adult population sample, their possible association with gender, oral behaviours, self-reported facial trauma and orthodontic treatment. Subjects older than 18 years were recruited from general population in public spaces during their daily life. A specific questionnaire was developed to collect data on TMD-pain, TMJ noises, oral behaviours, orthodontic treatment and facial trauma. A total of 4299 subjects were included in the study. The most common symptom in the sample was TMJ clicking (30.7%), followed by TMD-pain (16.3%) and TMJ crepitus (10.3%). Oral behaviours were reported in 29% of the sample; 43.6% of the sample reported a previous or ongoing orthodontic treatment. TMD-pain and TMJ clicking were significantly associated to gender, oral behaviours and a positive history of previous facial trauma. Crepitus was significantly associated to oral behaviours, facial trauma and higher age. Ongoing orthodontic treatment was significantly associated to TMD-pain and TMJ sounds. In a general Italian adult population sample, TMD-pain is associated to female gender and is less prevalent than TMJ clicking. TMDs are associated to trauma and oral behaviours.

The prevalence of oral stage dysphagia in adults presenting with temporomandibular disorders: a systematic review and meta-analysis

OBJECTIVE

Temporomandibular disorders (TMDs) are the most commonly experienced non-dental orofacial pain disorders, with pain and dysfunction potentially resulting in oral stage dysphagia (OD). However, limited research has been conducted on this condition, with potential negative effects on clinical practice. Therefore, the aim of this study was to determine the prevalence of OD in adults presenting with TMDs, diagnosed as per the Research Diagnostic Criteria for Temporomandibular Disorders or the Diagnostic Criteria for Temporomandibular Disorders protocols.

MATERIAL AND METHODS

A systematic review of the literature was completed. Nine electronic databases were searched from inception to January 2017, with no date/language restriction applied. Grey literature, conference proceedings, and reference lists were also searched. Studies presenting original data regarding OD prevalence in adults presenting with TMDs were included if they investigated impaired swallowing, mastication, masticatory pain or fatigue, or weight loss. Study eligibility and quality were assessed by two independent reviewers. Methodological quality was assessed using the Down's and Black tool.

RESULTS AND CONCLUSIONS

This search yielded 20 eligible studies. Swallowing itself was impaired in only 9.3% of patients with TMDs. A range of additional OD signs and symptoms were also commonly reported (e.g. masticatory pain (87.4%) and fatigue (62%)). Study limitations included the small number of studies which were eligible for inclusion. As signs and symptoms of OD are frequently reported by patients with TMDs, psychometrically robust prospective research is warranted to determine current and optimal management of this condition.

Correlation between age, gender, and the number of diagnoses of temporomandibular disorders through magnetic resonance imaging: A retrospective observational study

OBJECTIVE

The aim of this study was to evaluate the correlation among age, gender and the number of temporomandibular disorder (TMD) findings.

METHODS

The records from 228 patients with TMD were analyzed for the presence of these findings: morphological changes, disc displacement with reduction (DDWR) and without reduction (DDWOR), bone edema, effusion, and avascular necrosis. Statistical analyses were conducted using multinomial regression with a 5% significance level.

RESULTS

DDWR was the most frequent finding. Group 1 was composed of 94 patients (41.22%), Group 2, of 67 patients (29.38%), and Group 3, of 67 patients (29.38%). Men were significantly less likely to belong to Group 3 than women (p = 0.5517). Older patients were slightly more likely to fall in Groups 2 and 3 than in Group 1.

DISCUSSION

Women were shown to be more susceptible to developing a higher number of concomitant conditions than men, and the number of findings tended to increase with age.

Correlation between clinical variables and magnetic resonance imaging findings in symptomatic patients with chronic temporomandibular articular disc displacement with reduction: A retrospective analytical study

Objective: To correlate the clinical aspects of symptomatic patients with chronic articular disc displacement with reduction with alterations in the articular disc (AD) morphology and sagittal position. Methods: Records from 109 patients were selected that included data on AD morphology and sagittal position as determined by MRI. According to the MRI results, the sagittal position and AD morphology with opened and closed mouth were correlated with many clinical variables. Results: More than half of the patients studied were female, and the biconcave and hemiconvex morphologies were most common. Thirty-four patients (31.3%) presented with restricted maximum interincisal distance (MID). The biplanar morphology was associated with eccentric bruxism and MID (p < 0.05). Visual analog scale (VAS) scores between 2 and 7 were shown to be risk factors (p < 0.05). Conclusion: The mouth position can influence AD morphology and eccentric bruxism. VAS scores and unknown etiology were risk factors.

Prevalence, Nature, and Management of Oral Stage Dysphagia in Adults With Temporomandibular Joint Disorders: Findings From an Irish Cohort

PURPOSE

Temporomandibular disorders (TMDs) are caused by changes in the structure and/or function of the temporomandibular joint, masticatory muscles, and/or osseous components. TMDs can result in oral stage dysphagia (OD) with potential effects on function and patient well-being. Little is known about the prevalence, nature, and management of TMD-related OD. The aims of the present study were to estimate the prevalence and nature of OD in adult TMD patients and to identify the common management techniques used to manage the signs and symptoms of TMD-related OD.

PATIENTS AND METHODS

An 18-item subjective questionnaire was adapted from existing tools and used to investigate TMD etiology, the symptoms and signs of TMD-related OD, and the intervention techniques used to manage these symptoms. This was disseminated to 178 TMD patients consecutively recruited over 6 months in 2016. Descriptive and statistical methods were used to analyze the data.

RESULTS

Of the 178 TMD participants, 99% reported at least one symptom or sign of OD. Individuals presenting with subluxation of the jaw (80%), degenerative joint disorder (67%), and myofascial pain disorder (40%) reported OD most frequently. Common symptoms included painful mastication (90%), masticatory fatigue (78%), difficulties swallowing (33%), and difficulties drinking liquids (28%). The use of a broad range of management techniques was reported, with these including both OD-specific techniques (eg, diet modifications [81%]), and non-OD specific techniques (eg, analgesia [79%] and oral splints [75%]).

CONCLUSIONS

OD is prevalent, and difficulties with mastication are common in those with TMDs. The interventions used were diverse, with varying objectives and disparate levels of evidence supporting their efficacy within this cohort. Further research should address the epidemiology of TMD-related OD, evidence-based interventions, and the promotion of collaboration across the disciplines responsible for managing TMD-related OD (eg, speech and language therapy, oral and maxillofacial surgery, dentistry, restorative dentistry, orthodontics, oral medicine).

Predictors of arthrocentesis outcome on joint effusion in patients with disk displacement without reduction

OBJECTIVES

The aim of this study was to investigate the preoperative variables in patients with articular disk displacement without reduction that may influence the results of arthrocentesis on joint effusion (JE).

STUDY DESIGN

The records of 203 patients with clinical signs and symptoms of unilateral painful disk displacement without reduction and JE, confirmed by magnetic resonance imaging (MRI), and treated with arthrocentesis were selected. The following preoperative data were recorded: sex; age; joint side; pain duration; pain intensity, measurement with the visual analogue scale; and maximum interincisal distance (MID). All patients underwent a second MRI examination 3 to 4 months postoperatively to assess JE. The sample was then divided into 2 groups: group 1 (n = 160) comprised patients with no signs of JE; and group 2 (n = 43) comprised patients still showing signs of JE. Univariate and multivariate analyses were used to compare the groups.

RESULTS

Among the studied variables, pain duration (P = .0175), pain intensity (P < .0001), and MID (P = .0085) were shown to affect arthrocentesis outcomes. The longer the pain duration (odds ratio [OR] = 0.930), the more intense was the pain (OR = 0.346), and the smaller the MID (OR = 0.562), the less were the chances of arthrocentesis completely eliminating JE.

CONCLUSIONS

Pain duration, pain intensity, and MID can be used as predictors for the effect of arthrocentesis on JE outcomes and considered during treatment planning.

The Prevalence of Oropharyngeal Dysphagia in Adults Presenting with Temporomandibular Disorders Associated with Rheumatoid Arthritis: A Systematic Review and Meta-analysis

Temporomandibular disorders (TMDs) are the most frequent non-dental orofacial pain disorders and may be associated with rheumatoid arthritis (RA), resulting in oropharyngeal dysphagia (OD). However, clinicians' understanding of involvement with OD caused by RA-related TMDs is limited and the methodological quality of research in this field has been criticised. Therefore, the aim of this study was to systematically review the prevalence of oral preparatory and oral stage signs and symptoms of OD in adults presenting with TMDs associated with RA. A systematic review of the literature was completed. The following electronic databases were searched from inception to February 2016, with no date/language restriction: EMBASE, PubMed, CINAHL, Web of Science, Elsevier Scopus, Science Direct, AMED, The Cochrane Database of Systematic Reviews, and ProQuest Dissertations and Theses A & I. Grey literature and reference lists of the included studies were also searched. Studies reporting the frequency of OD in adults presenting with TMD and RA were included. Study eligibility and quality were assessed by three independent reviewers. Methodological quality was assessed using the Down's and Black tool. The search yielded 19 eligible studies. Typical difficulties experienced by RA patients included impaired swallowing (24.63%), impaired masticatory ability (30.69%), masticatory pain (35.58%), and masticatory fatigue (21.26%). No eligible studies reported figures relating to the prevalence of weight loss. Eligible studies were deemed on average to be of moderate quality. Study limitations included the small number of studies which met the inclusion criteria and the limited amount of studies utilising objective assessments. Valid and reliable prospective research is urgently required to address the assessment and treatment of swallowing difficulties in RA as TMJ involvement may produce signs and symptoms of OD.

Condyle Excursion Angle, Articular Eminence Inclination, and Temporomandibular Joint Morphologic Relations With Disc Displacement

PURPOSE

The aim of this study was to evaluate the relations of the condyle excursion angle (CEA) and the morphology and morphometry of the articular eminence to disc displacement (DD) using magnetic resonance imaging (MRI) of symptomatic patients.

MATERIALS AND METHODS

MRIs of 199 temporomandibular joints (TMJs) were evaluated. Qualitative and quantitative morphologic analyses were performed with tools available in PACS 11.0 (Carestream Health, Inc, Rochester, NY). The articular eminence inclination (AEI), eminence height (EH), CEA, and articular eminence morphologic shape were evaluated. Statistical analyses were used to evaluate any possible association of the variables with DD in the closed- and open-mouth positions, age, and gender. The significance level was set at .05.

RESULTS

Elderly women (>60 yr) presented higher prevalence values (43.26%). There was no statistical correlation between DD and gender (P = .4290). Higher mean values of the AEI and EH were associated with box-shaped eminences. The EH, AEI, and CEA were not related to the presence or absence of DD and the different types of DD. The AEI (P = .002) and CEA (P < .001) values were higher for TMJs with disc reduction in the open-mouth position.

CONCLUSION

Disc position in the closed- and open-mouth positions is not influenced by articular eminence morphology; however, the AEI and CEA have an influence on disc reduction.

Is There an Association Between Temporomandibular Joint Effusion and Arthralgia?

PURPOSE

The literature on joint effusion (JE) and its association with clinical and radiologic variables in patients with temporomandibular disorders (TMDs) is inconsistent and is characterized by multiple methodologic limitations. The primary aim of this investigation was to evaluate the association between magnetic resonance imaging (MRI) identified JE and temporomandibular joint (TMJ) arthralgia. The secondary aim of this investigation was to determine the association between JE and other clinical and MRI-identified soft tissue characteristics.

MATERIALS AND METHODS

A retrospective cohort study was conducted. Clinical and soft tissue imaging assessments were carried out according to the Diagnostic Criteria for Temporomandibular Disorders guidelines. The dependent variable was JE and the primary independent variable was arthralgia. The secondary independent variables were TMJ pain-associated characteristics and MRI-identified variables. When applicable, Pearson χ² or t test was used to determine the statistical associations between JE and clinical characteristics and between JE and MRI-identified variables. Furthermore, generalized estimating equation (GEE) modeling was conducted to determine which of the independent clinical and MRI-identified variables were associated with JE.

RESULTS

Data for 158 participants, representing 312 joints, were extracted. The mean age of the female sample (59.4%) was 31 ± 11.1 years and that of the male sample (40.6%) was 29.8 ± 9.7 years. No association was found between JE and arthralgia. However, statistically significant associations were found between JE and lateral disc rotation (P = .001) and between JE and disc position in the coronal and sagittal planes (P = .001). The GEE model suggested that disc displacement with reduction (odds ratio = 2.5) was a statistically relevant contributing factor for JE in the absence of degenerative joint disease.

CONCLUSION

Results associated JE with the position of the disc in the sagittal plane. No association was found between JE and arthralgia or TMJ pain-associated clinical characteristics in patients with TMDs.

Effect of Arthrocentesis on Symptomatic Osteoarthritis of the Temporomandibular Joint and Analysis of the Effect of Preoperative Clinical and Radiologic Features

PURPOSE

To evaluate the long-term outcome of arthrocentesis in patients with symptomatic temporomandibular joint (TMJ) osteoarthritis that was unresponsive to nonsurgical interventions.

MATERIALS AND METHODS

Seventy-nine patients (83 joints) with symptomatic TMJ osteoarthritis that had not responded to nonsurgical interventions and who underwent arthrocentesis were included in this study. Demographic, clinical, and radiologic data, including assessment of pain, dysfunction, improvement, and satisfaction, and maximal mouth opening were analyzed.

RESULTS

The analysis included 67 female patients (84.8%) and 12 male patients (15.2%), 13 to 70 years old, who were followed for 56.9 ± 6.7 months. Sixty-four (81%) reacted favorably to arthrocentesis. For these patients, maximal mouth opening increased from 26.3 ± 0.8 to 39.24 ± 0.9 mm (P < .001). Pain and dysfunction scores decreased from 6.92 ± 0.2 to 2.36 ± 0.3 (P < .001) and from 7.37 ± 0.2 to 2.24 ± 0.4 (P < .001), respectively. Overall score for patient satisfaction with arthrocentesis was 8.78 ± 0.3. The procedure had no lasting complications. Remarkably, the severity of preoperative pain, dysfunction, and range of motion and of radiographic changes did not correlate with the outcome of arthrocentesis. The severity of preoperative or postoperative signs and symptoms was not correlated with the severity of radiographic changes.

CONCLUSIONS

For most patients, arthrocentesis offers long-term favorable outcomes for symptomatic TMJ osteoarthritis that has not responded to nonsurgical treatments and otherwise would have required surgical arthroplasty. Severity of preoperative clinical and computerized tomographic findings is not predictive for the success of arthrocentesis. In addition, the lack of correlation between the clinical and radiologic findings negates the commonly used Wilkes classification, which presumes that the clinical signs and symptoms deteriorate together with radiologic changes.

Imaging Approach to Temporomandibular Joint Disorders

Internal derangement is the most common temporomandibular joint disorder. Degenerative osteoarthritis and trauma are next in frequency. Less common pathology includes rheumatoid arthritis, synovial chondromatosis, calcium pyrophosphate dehydrate deposition disease, pigmented villonodular synovitis, tumors, infection, and osteonecrosis. We provide a systematic approach to facilitate interpretation based on major anatomic structures: disc-attachments, joint space, condyle, and lateral pterygoid muscle. Relevant graphic anatomy and state of the art imaging are discussed in correlation with current clinical and therapeutic highlights of pathologic entities affecting the joint.

Diagnostic index of three-dimensional osteoarthritic changes in temporomandibular joint condylar morphology

This study aimed to investigate imaging statistical approaches for classifying three-dimensional (3-D) osteoarthritic morphological variations among 169 temporomandibular joint (TMJ) condyles. Cone-beam computed tomography scans were acquired from 69 subjects with long-term TMJ osteoarthritis (OA), 15 subjects at initial diagnosis of OA, and 7 healthy controls. Three-dimensional surface models of the condyles were constructed and SPHARM-PDM established correspondent points on each model. Multivariate analysis of covariance and direction-projection-permutation (DiProPerm) were used for testing statistical significance of the differences between the groups determined by clinical and radiographic diagnoses. Unsupervised classification using hierarchical agglomerative clustering was then conducted. Compared with healthy controls, OA average condyle was significantly smaller in all dimensions except its anterior surface. Significant flattening of the lateral pole was noticed at initial diagnosis. We observed areas of 3.88-mm bone resorption at the superior surface and 3.10-mm bone apposition at the anterior aspect of the long-term OA average model. DiProPerm supported a significant difference between the healthy control and OA group ([Formula: see text]). Clinically meaningful unsupervised classification of TMJ condylar morphology determined a preliminary diagnostic index of 3-D osteoarthritic changes, which may be the first step towards a more targeted diagnosis of this condition.

Estrogen via estrogen receptor beta partially inhibits mandibular condylar cartilage growth

OBJECTIVE

Temporomandibular joint (TMJ) diseases predominantly afflict women, suggesting a role for female hormones in the disease process. However, little is known about the role of estrogen receptor (ER) signaling in regulating mandibular condylar cartilage growth. Therefore, the goal of this study was to examine the effects of altered estrogen levels on the mandibular condylar cartilage in wild type (WT) and ER beta Knockout (KO) mice.

MATERIALS AND METHODS

21-day-old female WT (n = 37) and ER beta KO mice (n = 36) were either sham operated or ovariectomized, and treated with either placebo or estradiol. The mandibular condylar cartilage was evaluated by histomorphometry, proliferation was analyzed by double ethynyl-2'-deoxyuridine/bromodeoxyuridine (EdU/BrdU) labeling, and assays on gene and protein expression of chondrocyte maturation markers were performed.

RESULTS

In WT mice, ovariectomy caused a significant increase in mandibular condylar cartilage cell numbers, a significant increase in Sox9 expression and a significant increase in proliferation compared with sham operated WT mice. In contrast, ovariectomy did not cause any of these effects in the ER beta KO mice. Estrogen replacement treatment in ovariectomized WT mice caused a significant decrease in ER alpha expression and a significant increase in Sost expression compared with ovariectomized mice treated with placebo. Estrogen replacement treatment in ovariectomized ER beta KO mice caused a significant increase in Col2 expression, no change in ER alpha expression, and a significant increase in Sost expression.

CONCLUSION

Estrogen via ER beta inhibits proliferation and ER alpha expression while estrogen independent of ER beta induces Col2 and Sost expression.

3.0 Tesla MRI in the early evaluation of inferior alveolar nerve neurological complications after mandibular third molar extraction: a prospective study

OBJECTIVES

To evaluate the use of 3.0 T MRI in the prognosis of inferior alveolar nerve (IAN) sensory disorders after mandibular third molar extraction, in the early post-operative period.

METHODS

343 IANs were examined before and 3 days after surgery. Two radiologists evaluated the course of the nerve and the relative signal intensity (RSI). Cohen's kappa coefficient (κ) and intraclass correlation coefficient (ICC) were used to evaluate the interobserver (k = 0.891) and intra-observer variability (ICC = 0.927; 0.914, respectively). The IANs were divided into four groups on the basis of neurosensory disorders recovery time. ANOVA was used to evaluate the differences among the RSIs of the four groups, and multiple comparisons were performed with Tukey's range test.

RESULTS

No differences in the course of IANs were found before and after surgery. In 280 IANs, no iatrogenic paraesthesia was found (Group A). 63 IANs showed a neurosensory impairment. 38 IANs showed recovery of post-operative paraesthesia at 3-month follow-up (Group B). 16 IANs showed a full recovery of iatrogenic paraesthesia at 6-month follow-up (Group C). Seven IANs displayed a full recovery at 12-month follow-up and two IANs showed persistence of neurosensory disorders at 18-month follow-up (Group D). The one-way ANOVA results indicated statistically significant difference among all groups (p < 0.05), except between Groups C and D (p = 0.504).

CONCLUSIONS

The early evaluation of RSI values represents a valid tool to determine the prognosis of IAN sensory disorders after mandibular third molar extraction.