Internal Derangement of the Temporomandibular Joint

Unlocking the Temporomandibular Joint: CT, MRI, and Arthroscopic Correlation

The temporomandibular joint constitutes a synovial connection between the mandible and the skull base and plays a pivotal role in functions such as jaw movement, chewing, and verbal and emotional expression. Temporomandibular joint dysfunction is observed in about 30% of the population, with a higher prevalence in young to middle-aged women. Interestingly, a majority of individuals affected do not report pain, and only 5%-10% of symptomatic cases necessitate therapeutic intervention. The most common temporomandibular joint disorder manifests as pain in the masticatory muscles and is referred to as myofascial syndrome. However, articular disorders are also very common, usually due to disk displacement and degenerative or inflammatory arthropathies. Less frequently, the temporomandibular joint may be affected by a range of congenital and acquired conditions such as trauma and neoplasms. Imaging becomes necessary for the small percentage of patients who do not respond to conservative management or when there is uncertainty in the diagnosis. A comprehensive understanding of the normal imaging appearance of the temporomandibular joint as well as the wide range of potential pathologic conditions is essential for conducting an accurate radiologic assessment. Moreover, collaboration among multidisciplinary teams and the correlation of imaging findings with arthroscopic observations are crucial to advancing the diagnosis and treatment of temporomandibular joint dysfunction. ©RSNA, 2024 Supplemental material is available for this article.

Does intra-articular injection of platelet-rich plasma/platelet-rich fibrin improve outcomes after temporomandibular joint arthrocentesis? A systematic review and meta-analysis

Platelet-rich plasma (PRP) and platelet-rich fibrin (PRF) have been used as adjuncts to temporomandibular joint (TMJ) arthrocentesis but without any high-quality evidence. This systematic review collated data from published randomised controlled trials (RCTs) to provide level-1 evidence on its efficacy. Trials published on the databases of PubMed, Scopus, Embase, CENTRAL, and Web of Science up to 4 August 2023 and comparing intra-articular PRP/PRF with control after TMJ arthrocentesis were eligible. Primary outcomes were pain and maximal mouth opening (MMO). Twelve RCTs were included. Pooled analysis showed that pain scores were significantly reduced with the use of PRP/PRF as compared with control at one month (MD: -0.96 95% CI: -1.58 to -0.35 I2 = 86%), three months (MD: -1.22 95% CI: -1.86 to -0.59 I2 = 85%), and ≥six months (MD: -1.61 95% CI: -2.22 to -1.00 I2 = 88%). Similarly, MMO was significantly improved in the PRP/PRF group at one month (MD: 2.40 95% CI: 1.02 to 3.77 I2 = 88%), three months (MD: 3.17 95% CI: 1.63 to 4.72 I2 = 91%), and ≥six months (MD: 2.98 95% CI: 1.86 to 4.10 I2 = 75%) as compared with the control group. Subgroup analysis for PRP and PRF failed to show any difference in outcomes. Moderate quality evidence suggests that PRP and PRF may significantly improve pain and MMO when used as adjuncts to TMJ arthrocentesis. Due to the small effect size, the clinical significance of the results is questionable. The high heterogeneity in PRP/PRF preparation methods is a significant limitation.

Clinical and demographic factors associated with the effectiveness of temporomandibular joint arthroscopy

PURPOSE

High success rates and minimal complications have consolidated arthroscopy as the therapeutic alternative of choice for minimally invasive treatment of internal disorders (ID) of the temporomandibular joint (TMJ). However, there is no certainty regarding the demographic and clinical factors associated with the technique's success or failure. This study was performed to analyze the effectiveness of arthroscopy regarding pain and the mandibular dynamics and also to determine whether variables such as age, sex, and preoperative Wilkes stage influence the results.

METHODS

A retrospective study was conducted involving 92 patients with ID of the TMJ between September 2017 and February 2020. In all cases, a first stage of intra-articular lysis and lavage was executed. As needed, a phase of operative arthroscopy or arthroscopic discopexy was implemented.

RESULTS

A total of 152 arthroscopies were performed. Both the variation in pain and mouth opening in patients with ID of the TMJ treated were statistically significant for the follow-up periods studied. Better results were observed for patients with lower Wilkes stages. No association with age was found.

CONCLUSION

Based on the results, we recommend early intervention as soon as an ID in the TMJ is detected.

Effect of pre-stress on dynamic finite element analysis of the temporomandibular joint

The pre-stress of the temporomandibular joint (TMJ) at the intercuspal position (ICP) was often neglected, which would cause errors in the finite element analysis. The purpose of this study was to investigate the effect of pre-stress on dynamic finite element analysis of the TMJs. One healthy female adult was recruited for medical imaging and motion data acquisition of the reference position (RP) to the ICP and the clicking teeth. The three-dimensional maxillofacial model including the maxilla, mandible, articular cartilages, discs, and discal attachments was reconstructed. Motion from the RP to the ICP was simulated to obtain pre-stress at the ICP. Two groups of the clicking teeth were simulated: (1) the group without pre-stress (GWoP); (2) the group with pre-stress (GwP). Significant differences were found between the two groups at the initial moment of movement, during the open-mouth phase, and during the collision phase between the upper and lower teeth. The maximum difference in the discal contact stress between both groups was even more than double. The relaxation of the TMJ at the beginning of the mouth opening was simulated in the GwP. In addition, an increase in the TMJ stress during teeth tapping was simulated in the GwP. These were not reflected in the GWoP. If pre-stress at the ICP was not considered, part of the true results would be lost. It is necessary to consider pre-stress in the dynamic finite element analysis of the TMJ.

Evaluation of clinical signs and magnetic resonance imaging findings in patients with temporomandibular disorders

This study assessed the relationship between clinical symptoms and magnetic resonance imaging (MRI) findings in temporomandibular disorders (TMD). A total of 324 temporomandibular joints (TMJs) from 162 patients were included. The TMJs were divided into three groups based on disc positions on MRI: normal disc position, anterior disc displacement with reduction (ADDwR), and anterior disc displacement without reduction (ADDwoR). Clinical findings included TMJ pain, TMJ noise, and maximum mouth opening (MMO). The disc configuration, disc positions, condylar morphology, and joint effusion were evaluated in proton density-weighted and T2-weighted open and closed-mouth sagittal sections. Patients comprised 135 females and 27 males, with a mean age of 37.63 ± 13.86 years. The VAS score was significantly higher in ADDwoR than in ADDwR (p = 0.007). Condylar sclerosis (β coefficient: 1.449, 95% confidence interval (CI): 0.505-2.393, p = 0.003) and condylar flattening (β coefficient: 1.024, 95% CI: 0.209-1.840, p = 0.014) had higher VAS scores than the other MRI findings in multiple regression analyses. Limited mouth opening (MO) was independently associated with ADDwoR. ADDwoR had a higher risk of having limited MO than normal disc position (odds ratio: 5.268), while there were no associations between limited MO and other MRI findings. None of the MRI findings showed significant performance in predicting TMJ noise. The convex and folded disc configuration percentages, the frequencies of osteophyte formation, and grade 3 effusion were significantly higher in the ADDwoR group. More severe clinical symptoms and a higher degree of disc deformity, osteophyte formation, and high-grade effusion were shown to be associated with ADDwoR.

Temporomandibular Joint Facts and Foibles

The purpose of this article is to dispel some of the major foibles associated with the etiology and management of TMJ disorders, while presenting some of the facts based on the scientific literature to date. To appreciate this kind of update, the reader must be an "out of the box thinker" which requires openness to new ways of seeing the world and a willingness to accept new concepts based on evolving evidence.

Arthrocentesis Versus Level 1 Arthroscopy in Internal Derangement of Temporomandibular Joint

Introduction

Internal derangement of the temporomandibular joint is defined as an abnormal position of the articular disc in relation with mandibular condyle and articular eminence presenting as disc displacement with or without reduction.

Methodology

This study was conducted on thirty patients diagnosed with Internal derangement of TMJ consisting of 8 males and 22 females averaging 34.6 years. Two groups Conventional Arthrocentesis (Group A) and Level 1 Arthroscopy (Group B) consisted of 15 cases each divided alternately. Clinical evaluation parameters included VAS for pain, maximal interincisal opening, deviation on mouth opening, range of motion including lateral excursion & protrusion movements recorded at 1 week, 1 month & 6 months postoperatively. Wilke's Staging according to MRI findings was recorded preoperatively and 6 months postoperatively.

Results

At 6 month follow-up, average reduction in VAS for pain & deviation on mouth opening was 72.43% & 24.73% in Group A and 77.66% & 65.41% in Group B, respectively. Average increase in MIO, right & left excursion & protrusion movements was 29.55%, 31.33%, 20.12% & 32.45% in Group A and 34.94%, 41.37%, 39.29% and 36.51% in Group B, respectively. Improved results were obtained clinically for all Wilke's stages in both groups with more number of patients improving in Group B.

Conclusion

On comparing results, improvement was observed in various clinical evaluation parameters of both the groups at 6 months follow-up. However, statistically significant & better results were obtained for the Arthroscopy group.

Efficacy of arthrocentesis with intra-articular injection of hyaluronic acid and corticosteroid in the treatment of internal derangement of temporomandibular joint

Introduction

Various techniques have been used to treat internal temporomandibular joint derangements (TMJ ID), with arthrocentesis one of the most successful in reducing symptoms and promoting function. In cases of TMJ ID, this research study compares and evaluates the efficacy of arthrocentesis with injections of corticosteroids (CS) or hyaluronic acid (HA).

Methods

This prospective randomized, non-blinded study involving 91 patients with symptoms of TMJ ID treated by arthrocentesis followed by intra articular injection of 1 ml of either corticosteroid (group A) or HA (group B) . Maximum mouth opening, lateral excursive movements, TMJ pain at rest and during function, masticatory efficiency, pre-treatment functional TMJ limitation and subjective judgment of efficacy of treatment were assessed with millimeter scale. All the parameters measured before the procedure and further followed at 1st week, 1st month, 3rd month and 6th month post-procedure.

Results

Maximum mouth opening post procedure improved significantly in Group B at follow up visits (P < 0.05). Subjects in group B showed significant reduction in pain at rest (P = 0.001) at 1 week and 1 month follow up & increased masticatory efficiency at 6 months (P = 0.042) as compared to that of group A subjects.

Conclusion

Injection of HA post-TMJ arthrocentesis is found be comparatively more effective method of treating TMD IDs with resultant decrease in pain & improved functionality of the jaw. TMJ arthrocentesis along with injection of HA could serve as a possible alternative to treat chronic TMJ pain sufferers who are unresponsive to conservative medical therapies.

Chronic craniomandibular pain after craniotomy: A long-term clinical study

OBJECTIVE

Chronic craniomandibular/cervical pain and temporomandibular disorders have not been studied in patients who had a craniotomy several years previously. The aim of the current clinical work was to address these issues.

METHODS

A total group of 150 ambulant patients who had a previous craniotomy was subclassified according to whether or not the temporalis muscle was manipulated.

RESULTS

The average incidence of multiple subsite regional head and neck pain was 69.3% a number of years after a craniotomy. Evidence of internal derangement of the temporomandibular joint was significantly higher in the group that required manipulation of the temporalis muscle during the procedure.

CONCLUSION

The pattern of chronic craniomandibular/cervical pain experienced years after a craniotomy supports the brain neuromatrix theory of pain.

A clinical study on the incidence of internal derangement of the temporomandibular joint following harvesting of temporalis fascia

OBJECTIVE

The aim of the current clinical study was to reveal whether harvesting of a temporalis fascia graft would be associated with a higher incidence of temporomandibular joint (TMJ) internal derangement.

METHODS

The study group involved 104 patients who had middle-ear operations, 67 of which involved harvesting of temporalis fascia and 37 that did not. The TMJs were clinically examined in each group.

RESULTS

The total incidence of internal derangement of the TMJ was significantly higher in the group that had temporalis fascia harvesting (79.1%), compared to the group that did not have temporalis fascia harvesting (29.7%), (p= 0.001).

CONCLUSION

Harvesting of temporalis fascia probably alters mandibular kinematics and predisposes to internal derangement of the TMJs.

Current Treatment Strategies for the Management of the Internal Derangements of the Temporomandibular Joint: A Global Perspective

Internal joint derangement is a disruption of the internal aspects of the TMJ-disc displacements/adhesions/impingements, causing alterations in the normal dynamic motions of the joint. Clinicians must be diligent in establishing the correct diagnosis and cause of TMJID, which ultimately leads to the appropriate management of such patients. While many patients adapt over time or with non-surgical treatment, surgery may be indicated for those with ongoing problems. The surgical pyramid provides a stepwise progression for TMJ surgical patients. This paper aims to review TMJID and its management with special emphasis on arthroscopic minimally invasive surgery, as practised in other countries around the world, and compare this to current education, understanding and practice in India. Currently, India is lagging behind in providing the full scope of TMJ services as there are very few surgeons trained in the skill of arthroscopic techniques. There needs to be continued expansion of our understanding of TMJID treatment in India to bring it level with the rest of the world.

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.

An International Survey on Temporomandibular Joint Surgeon's Implementation and Management of Discectomy in Treating Temporomandibular Joint Internal Derangement

PURPOSE

To survey temporomandibular joint (TMJ) surgeons to determine current practice trends and perceptions regarding the role of discectomy for the treatment of TMJ internal derangements.

METHODS

An anonymous 5-part web-based survey was sent to TMJ surgeons. The survey was created and distributed, and the data were collected with the University of Michigan Qualtrics platform. Responses were compared based on operative volume, tendency to replace the disc, and likelihood of requiring temporomandibular joint replacement (TJR) after discectomy. Spearman correlations were used to test statistically significant differences. Domain-level analyses were also performed by summarizing items into 3 domain scores. Analyses were performed in SAS V9.4 (SAS Institute Inc., Cary, NC, USA).

RESULTS

Fifty-nine surgeons (33.9%) completed the survey. Discectomy was not considered to be a useful procedure by 85% of respondents, and 74% would not consider discectomy as a first surgical option. Most would consider discectomy (64%) before alloplastic total joint replacement. Discectomy was preferred over discopexy for the management of anterior disc displacement with reduction by high volume surgeons (89%), but most (72%) did not feel that discectomy was beneficial over arthroscopy in the treatment of anterior disc displacement without reduction and concomitant degenerative bony changes. In managing symptomatic disc perforation, 66% agreed that discectomy is the procedure of choice and 49% felt that interpositional tissue is indicated in most cases after discectomy. Respondents who reported fewer re-operations requiring alloplastic TJR after discectomy had, on average, more positive perceptions of discectomy on the benefits domain (P = .03), better than alternatives domain (P = .03), and fewer concerns on the perceived adverse effects domain (P = .03).

CONCLUSIONS

TMJ surgeons do not employ TMJ discectomy in most cases of TMJ internal derangement. However, discectomy is considered useful in cases of disc perforation or for persistent symptomatic disc displacement without reduction, in an attempt to avoid alloplastic TJR. Common adverse effects included joint noises and osteoarthrosis, and the use of interpositional disc replacement tissue did not alter the incidence of adverse effects or complications reported.

Transitioning to chronic temporomandibular disorder pain: A combination of patient vulnerabilities and iatrogenesis

Background

Based on a variety of studies conducted in recent years, some of the factors that might contribute to the negative treatment responses of some TMD patients have been elucidated.

Methods

This paper describes known vulnerability factors that make individuals susceptible to developing temporomandibular disorders (TMDs), as well as those that contribute to the perpetuation of such problems. In addition, the topic of iatrogenesis is discussed as a major contributor to the negative outcomes that can be seen in this field.

Results

At the patient level, anatomical, psychosocial and genetic factors may contribute to individual vulnerability. The anatomy and pathophysiology of muscles, joints, disc and nerves may all be involved in predisposing to TMD symptoms, especially when the patients have pain elsewhere in the body. Among the psychosocial factors, some features may be elucidated by the DC/TMD axis II, while others (eg illness behaviour, Munchausen syndrome, lack of acceptance of non‐mechanical approaches) require careful evaluation by trained clinicians. Genetic predisposition to first onset TMDs and to chronification of symptoms has been identified for individuals with certain psychological traits, presence of comorbid conditions and certain abnormal clinical manifestations. Regarding iatrogenesis, sins of omission may influence the clinical picture, with the main ones being misdiagnosis and undertreatment. Joint repositioning strategies, occlusal modifications, abuse of oral appliances, use of diagnostic technologies, nocebo effect and complications with intracapsular treatments are the most frequent sins of commission that may contribute to chronification of TMDs. The patients who present with massive occlusal and jaw repositioning changes combined with persistent severe orofacial pain are not a rarity within TMD and orofacial pain canters; these patients are the most difficult ones to manage because of this horrific combination of negative factors.

Conclusions

The information presented in this paper will help clinicians to understand better why some individuals develop temporomandibular disorders, why some of them will progress to becoming chronic patients, and what the appropriate responses may be.

Is the Temporomandibular Joints' Reciprocal Clicking Related to the Morphology and Position of the Mandible, as Well as to the Sagittal Position of Lower Incisors?-A Case-Control Study

The number of patients diagnosed with temporomandibular joint (TMJ) internal derangements, who are seeking orthodontic treatment, is increasing. The aim of the study was to assess the relationship between the presence of TMJ reciprocal clicking and the morphology and position of the mandible, and position of lower incisors, examined on the lateral cephalograms. Fifty patients diagnosed with reciprocal clicking in at least one of the TMJs and 55 patients with no symptoms of TMJ dysfunction were included in the study. Cephalometric analysis was used for the assessment of: skeletal class, sagittal and vertical position of the mandible, angle of the mandible, inclination of the mandibular ramus and the mandibular corpus, as well as for the assessment of the position of the mandibular incisors. The statistical significance level was set at p = 0.05. There were no statistically significant differences between the examined groups regarding the sagittal and vertical position of the mandible, as well as regarding the sagittal position of the mandibular incisors. Presence of TMJ reciprocal clicking is not associated with the position and the morphology of the mandible, as well as with the sagittal position of the mandibular incisors. Patients with early stages of TMJ internal derangements do not present any significant changes in Cephalometrics. Patients diagnosed with TMJ internal derangements before orthodontic treatment require an interdisciplinary approach to the treatment, including physiotherapy.

Mandibular asymmetry as a possible etiopathologic factor in temporomandibular disorder: a prospective cohort of 134 patients

OBJECTIVES

The present study aimed to investigate mandibular asymmetry as a possible etiopathologic factor in temporomandibular disorder (TMD).

MATERIALS AND METHODS

A prospective cross-sectional study of patients with dentofacial deformities seeking corrective orthognathic surgery was conducted. The pre-operative prevalence of TMD in patients with mandibular asymmetry and other dentofacial deformities was assessed using the Diagnostic Criteria for TMD (DC/TMD) Axis I protocol.

RESULTS

A total of 134 patients were recruited - 82 with mandibular asymmetry and 52 without. There was a significantly higher prevalence of TMD in those with mandibular asymmetry (67.1%; 95% CI 59 to 75%) compared to those without (40.4%; 95% CI 32 to 49%, p = 0.002). The overall pre-operative prevalence of TMD in this population of patients was 56.7% (95% CI 48 to 65%). Pain disorder only was present in 9.7%, TMJ disorder only in 29.9%, and both pain and TMJ disorders in 17.2%. The most prevalent type of TMD is disc displacement with reduction (77.6%), followed by myalgia (35.5%) and arthralgia (21.1%).

CONCLUSION

The prevalence of TMD in those with mandibular asymmetry was significantly higher than those without, suggesting that mandibular asymmetry could be a possible etiopathologic factor in TMD.

CLINICAL RELEVANCE

The significantly higher prevalence of temporomandibular disorder in those with mandibular asymmetry suggests that we need to be especially cognizant of this condition in our pre-operative, surgical, and post-operative management of this group of orthognathic patients.

Incobotulinum toxin type A for treatment of chronic myofascial pain

PURPOSE

This study assessed the effectiveness of incobotulinum toxin type A (IBTx) for chronic myofascial pain affecting the masseter and temporal muscles.

METHODS

Twenty two patients who received a diagnosis of chronic masseter and temporalis myofascial pain were evaluated by using a visual analog pain scale (VAS), digital pressure algometry, and the SF-36 Health Survey at baseline (T0), before IBTx injection. Patients were again evaluated at 2 months (T1) and 7 months (T2) after IBTx injection.

RESULTS

VAS scores for pain significantly differed (P = 0.029, Friedman test). Post-hoc tests showed a significant reduction in pain at 2 months (T0-T1) and 7 months (T0-T2) (P = 0.011 and P = 0.028, respectively; Wilcoxon test) but not between 2 and 7 months (P = 0.676; Wilcoxon test). There was no significant difference in pressure algometry values (P = 0.385, Friedman test). Quality of life (QOL) assessment showed a significant difference (P = 0.002, Friedman test). Post-hoc tests showed a significant improvement in QOLat 2 months, but no significant difference at 7 months (P = 0.004 and P = 0.260, Wilcoxon test).

CONCLUSION

IBTx injection resulted in safe, effective short-term pain relief for patients with chronic facial pain affecting the masseter and temporalis muscles.

Evaluation of prolotherapy in comparison with occlusal splints in treating internal derangement of the temporomandibular joint - A randomized controlled trial

PURPOSE

The aim of this study was to compare the efficacy of dextrose prolotherapy with that of occlusal splints in treating internal derangement of the temporomandibular joint.

PATIENTS AND METHODS

A total of 34 patients with temporomandibular joint internal derangement classed as Wilkes stages II or III were recruited for the study, and were randomly divided into study and control groups with 17 patients each. The patients in these control and study groups were treated with splints and prolotherapy, respectively. Outcome parameters, such as pain, mouth opening, clicking and deviation, were assessed using the Helkimo clinical dysfunction index for a review period of 1 year.

RESULTS

Nine patients in the study group had complete absence of pain, compared with only one patient in the control group. The results showed that patients who received prolotherapy demonstrated improvement in pain (p < 0.001), mouth opening (p = 0.032), and clicking (p < 0.001), but no significant difference in deviation was observed between the groups after 1 year (p = 0.862).

CONCLUSION

Prolotherapy was found to be superior in providing long-term clinical relief, with reduction in pain and clicking along with improved mouth opening.

Computer-Guided Arthrocentesis Using Patient-Specific Guides: A Novel Protocol for Treatment of Internal Derangement of the Temporomandibular Joint

PURPOSE

The aim of the present study was to evaluate the accuracy of 3-dimensionally (3D) printed patient-specific guides (PSGs) to direct the passage of inlet and outlet needles into the superior joint spaces of the temporomandibular joint (TMJ) in preparation for arthrocentesis.

PATIENTS AND METHODS

The present study included 10 patients with 14 TMJs with anterior disc displacement with reduction. A 3D PSG was designed for each patient to lead the inlet and outlet needles into the superior joint space of the TMJ. The PSGs were implemented, and their accuracy for guiding the needles into the superior joint space was assessed.

RESULTS

Both arthroscopic verification and clinical evaluation revealed that direct access to all the predetermined anatomic locations inside the TMJs had been obtained, except for 1 case, during which the patient had failed to maintain the maximum mouth opening during computed tomography scanning.

CONCLUSIONS

The virtual computer-initiated PSGs were beneficial for directing the passage of the needles into the superior joint space.

Computerized ultrasonic axiographic evaluation of condylar movement in patients with internal derangement of the temporomandibular joint

OBJECTIVES

To evaluate condylar movement during lateral excursion in individuals with internal derangement of the temporomandibular joint (TMJ) using ultrasonic axiography.

MATERIALS AND METHODS

A total of 34 patients with internal derangement of the TMJ and 34 participants in the control group were examined. Mandibular functional movement was recorded by ultrasonic axiography. Three-dimensional condylar movement was measured in the working and balancing condyles.

RESULTS

Significant differences in condylar movement were found between the two groups. In the group with internal derangement of the TMJ, the three-dimensional linear distances of the condylar path in a working condyle were greater than in the control group during lateral excursion. The speed of the balancing condyle in the returning path of lateral excursion was significantly greater in the group with internal derangement than in the control group.

CONCLUSIONS

The results of the present study indicate that internal derangement of TMJ may affect the working and balancing condylar movements during lateral excursion.

18F-NaF PET/CT for the evaluation of temporomandibular joint disorder

AIM

To investigate the usefulness of a quantitative parameter (maximum standardised uptake value [SUVmax]) of ¹⁸F-sodium fluoride (NaF) positron-emission tomography (PET)/computed tomography (CT) for the evaluation of temporomandibular joint (TMJ) disorder (TMD).

MATERIALS AND METHODS

Seventy-six TMD patients (male: female=14:62, age=40.3±17.1 years, bilateral: unilateral=40:36) with 152 TMJs were enrolled. The ¹⁸F-NaF PET/CT parameter (SUVmax) was compared with the presence of TMJ arthralgia (arthralgic=86, non-arthralgic=66) and clinical subtypes based on the Research Diagnostic Criteria for TMD Axis I (TMD osteoarthritis=49, non-TMD osteoarthritis=67, and asymptomatic TMJ=36). Splint therapy was applied to 48 patients for 6 months without considering ¹⁸F-NaF PET/CT findings. Post-splint therapy ¹⁸F-NaF PET/CT was performed in 32 patients and clinical responses to the therapy were classified into improvement (n=33), no change (n=10), or aggravation (n=7) for 50 TMJs excluding asymptomatic TMJs (n=14).

RESULTS

SUVmax was significantly greater in arthralgic TMJs than in non-arthralgic TMJs (6.62±3.56 versus 4.32±1.53, p<0.0001). SUVmax was also significantly greater in TMD osteoarthritis (6.75±3.85) than in non-TMD osteoarthritis (5.21±2.70) and asymptomatic TMJs (4.86±1.99; p=0.0386). After splint therapy, SUVmax was significantly increased in aggravated TMJs (from 7.80±3.72 to 11.00±5.74, p=0.0156), whereas no significant change in SUVmax was observed in improved (from 6.16±2.68 to 6.09±2.60, p=0.4915) and unchanged (from 6.46±4.19 to 6.77±4.32, p=0.3223) TMJs.

CONCLUSIONS

¹⁸F-NaF PET/CT is a useful imaging tool for TMD evaluation because SUVmax showed a fair diagnostic performance for arthralgic TMJ and TMD osteoarthritis, and a correlation with the therapeutic response.