Disc Displacement With Reduction Research Articles

Pain, Function and Quality of Life in Temporomandibular Disorder Patients With Different Disc Positions.

Whether pain, jaw function and quality of life are correlated with disc positions is controversial, and similar studies evaluating disc positions by magnetic resonance imaging (MRI) are very limited. This study evaluated the pain, mandibular function and quality of life of the temporomandibular disorders (TMDs) patients with different disc positions according to MRI, and the relationship among them. Three hundred and thirty-five participants were included. Patients completed questionnaires included the Numeric Rating Scale (NRS), Jaw Functional Limitation Scale 8-item (JFLS-8), the Generalised Anxiety Disorder 7-item (GAD-7), Patient Health Questionnaire 9-item (PHQ-9) and Oral Health Impact Profile for TMD (OHIP-TMD). MRI was conducted to evaluate these diagnoses, resulting in the identification of three distinct categories: normal positioning (NP), disc displacement with reduction (DDwR) and disc displacement without reduction (DDwoR). Participants had the mean age of 28.55 ± 11.10 years (80.90% women). DDwR and DDwoR had a higher percentage of females compared with NP. Significant differences existed among patients in all questionnaires. The DDwoR group had significantly the highest pain, functional limitation and the worst quality of life. Moreover, they experienced the most difficulties in chewing tough foods, yawning, experiencing pain and psychological discomfort. Moreover, the multivariate regression showed that age, female gender, diagnosis as DDwoR, GAD-7 and PHQ-9 were significantly linked to higher functional limitation. Worse quality of life was associated with age, diagnosis as DDwoR, GAD-7 and PHQ-9. Among patients with different disc positions, DDwoR showed the highest pain, functional limitation and the worst quality of life. Also, NP showed a proportion of chronic pain. Physical pain, psychological discomfort and chewing tough food were regarded as the most impaired. Women who experience anxiety and depression tended to have a higher propotion of dysfunction and a lower quality of life.

Cone beam computed tomography evaluation of condyle position and joint space in a group of intra-articular disorders patients undergoing stabilization splint treatment

This cross-sectional study assesses condyle position and joint space using Cone Beam Computed Tomography (CBCT) in patients with intra-articular disorders undergoing stabilization splint treatment. Patients are categorized into three groups based on MRI findings: no disc displacement (no DD), disc displacement with reduction (DDwR), and disc displacement without reduction (DDwoR). The study involves 35 patients, each with at least one DDwR joint. CBCT evaluates joint space and condyle position, revealing wider anterior, posterior, and superior joint spaces in both DDwR (anterior: 2.48 ± 0.98mm; posterior: 1.83 ± 0.71mm; superior: 2.46 ± 0.81mm) and DDwoR groups (anterior: 2.41 ± 1.13mm; posterior: 2.65 ± 1.14mm; superior: 2.74 ± 0.88mm) compared to the no DD group. Posterior condyle position accounts for the highest prevalence, at 60.4%, in DDwR joints. While no significant difference is noted in condyle position and anterior and superior joint space among three groups, a significant difference is observed in posterior joint space between groups (p < 0.05). The study suggests that joint space may be greater in joints with disc displacement, and posterior condyle position likely predominates in joints with and without disc displacement. However, further research is needed due to the small sample size.

Ultrasound-Guided Vs Non-Guided Prolotherapy for Internal Derangement of Temporomandibular Joint. A Randomized Clinical Trial.

This randomized clinical trial study aims to compare ultrasound-guided versus non-guided Dextrose 10% injections in patients suffering from internal derangement in the temporomandibular joint (TMJ). The study population included 22 patients and 43 TMJs suffering from unilateral or bilateral TMJ painful clicking, magnetic resonance imaging (MRI) proved disc displacement with reduction (DDWR), refractory to or failed conservative treatment. The patients were divided randomly into two groups (non-guided and ultrasound (US)-guided groups). The procedure involved injection of 2 mL solution of a mixture of 0.75 mL 0.9% normal saline solution, 0.3 mL 2% lidocaine and 0.75 mL dextrose 10% using a 25G needle in the joint and 1 mL intramuscular injection to the masseter muscle at the most tender point. The Visual Analogue Score (VAS) was used to compare joint pain intensity over four different periods, beginning with pre-injection, 1-, 2-, and 6-months postinjection. Twenty-two patients 5 males (n = 5/22, 22.7%) and 17 females (n = 17/22, 77.2%) were included in this study. The mean age was 27.3 ± 7.4 years (30.2 ± 7.0) for the non-guided group and 24.3 ± 6.9 for the US-guided group. The dextrose injection reduced intensity over time in both groups with statistically significant improvement (P value <.05) at 2 and 6 months in both groups. There was no statistically significant difference in VAS assessment between both groups. Intra-articular injection of dextrose 10% for patients with painful clicking and DDWR resulted in reduced pain intensity in both US-guided and non-guided groups with significant symptomatic improvement over time in both groups. US guidance allowed accurate anatomical localization and safe procedure with a single joint puncture.

Effect of the application of digital technology-assisted optimization in the process of adjusting jaw position.

The aim of this study was to demonstrate a novel jaw position adjustment technique derived from digital twins and evaluate the application effect of digital technology-assisted optimization in the process of adjusting jaw position on patients with temporomandibular disorders (TMD). A total of 74 patients with TMD who attended the Department of Temporomandibular Joint, West China Hospital of Stomatology, Si-chuan University, between June 2022 and May 2023 were selected. The patient's initial computed tomography (CT) and bilateral temporomandibular joint data obtained by magnetic resonance imaging (MRI) were collected. The 148 joints were divided into the normal disc-condyle relationship (N) group, disc displacement with reduction (DDWR) group, and disc displacement without reduction (DDWoR) group. Assisted by digital technology, the patient's CT data were reconstructed, and a personalized reference plane was established to adjust the jaw position. A three-point bite guiding splint was designed by the adjusted occlusal space and then fabricated by 3D printing technology. It was worn by the patients and then reviewed by MRI. Before and after the adjustment of jaw position, the amount and direction of condyle and disc displacement and the angle between condyle and disc were measured as the evaluation indexes of the effect of the adjustment. The correlation with condylar displacement was evaluated. In the N group, the disc moved backward and downward along the X and Z axes by (-0.60±0.62) and (0.51±0.71) mm, respectively. In the DDWR group, the disc moved backward and upward along the X and Z axes by (-1.33±1.38) and (-0.09±1.31) mm, respectively. In the DDWoR group, the disc moved forward and downward along the X and Z axes by (0.49±1.76) and (1.35±1.76) mm, respectively. The angle between the condyle and the disc decreased after adjustment of the jaw position in all three groups. All patients showed improvement in symptoms after adjustment. Digital technology-assisted jaw position adjustment can simplify the process, reduce the sensitivity of the technique, and improve patients' disc-condyle structure and symptoms. Therefore, its application in the treatment of patients with TMD is of great clinical significance.

Effectiveness of anterior repositioning splint versus other occlusal splints in the management of temporomandibular joint disc displacement with reduction: A meta-analysis.

Disc displacement with reduction (DDwR) is among the common disc disorders of temporomandibular joint (TMJ), which can be managed conservatively by splint therapy. Anterior repositioning splint (ARS) is the most commonly prescribed splint by dental practitioners, but not getting a normal disc-condyle relationship always and other side effects lead to need of comparing with other occlusal splints. This review will help in informed decision-making by clinicians in choosing an appropriate splint type for patients. The aim is to compare the effectiveness of ARS in the management of DDwR with other occlusal splints for TMJ and muscle pain, TMJ noise, any adverse effects, regaining normal disc-condyle relationship. We followed published protocol in the International prospective register of systematic reviews. Databases were searched till May 2023 using different search strategies as per the database. Title and abstract screening, followed by full-text screening and data extraction with risk of bias, was done by two independent reviewers in Covidence. Outcomes were reported as risk ratio (RR) or mean difference (MD) for dichotomous or continuous outcomes, respectively, using RevMan 5.4 (Review Manager 5.4) software. We used a random effect model for statistical analysis. Certainty of evidence was assessed using the Grading of Recommendation, Assessment, Development, and Evaluation Guideline Development Tool (GRADEpro GDT) software. A total of 1145 reports were found from a database search. After screening, four studies were included for systematic reviews. Other occlusal splints reported were sagittal vertical extrusion device and mandibular ARS, full hard stabilization splint of canine or centric stabilization type. Data of only two studies could be used for meta-analysis having 30 participants received ARS and 40 received other occlusal splints. We did not find evidence of any difference between ARS and other occlusal splints for TMJ clicking in short term (RR 1.25, 95% confidence interval [CI] 0.91-1.72) but a small difference in favor of other occlusal splint in long term (RR 2.40, 95% CI 1.04-5.55). No evidence of any difference was found between both treatments for TMJ pain in short term (MD-5.68, 95% CI-17.31-5.95) and long term (MD 0.00, 95% CI-2.86-2.86) and muscle pain in short term. The certainty of evidence for comparison of two treatments for different outcomes was of low or very low level. Evidence is uncertain that other occlusal splints reduced TMJ clicking slightly in comparison to ARS. For the remaining outcomes, no evidence of any difference was found between the two splints and it may be biased due to selection bias, inadequate blinding of participants, and outcome assessor.

Severity of Temporomandibular Joint Disc Displacement and Generalized Joint Hypermobility in Growing Patients: A Cross-Sectional Magnetic Resonance Image Study

Background: This study aimed to investigate the association between the internal derangement of the temporomandibular joint (TMJ), in particular the severity of disc displacement (DD), and the presence of generalized joint hypermobility (GJH) in growing patients evaluated on magnetic resonance images (MRIs). The study also investigated the relationship between the stages of DD severity and age. Methods: This cross-sectional study has been conducted on a pre-orthodontic population (8–16 years). The GJH was assessed with the Beighton test (cutoff ≥ 4) and the final sample of 56 patients was divided into two groups: a study group, 30 subjects with GJH, and a control group, 26 subjects without GJH. The disc position was evaluated on MRI and the severity of DD was classified in four stages. Pearson’s χ2 Test was performed for the analysis of the statistical correlation. Results: A statistically significant relationship between GJH and disc position was found, in particular, a disc displacement with reduction (DDwR) and DD severity. A positive association also emerged between the severity of DD and age, that increased with increasing age. Conclusions: The research results suggest that there is an association between the presence of generalized joint hypermobility (GJH) and disc displacement (DD) in growing patients. Growing patients with GJH showed a higher severity of DD. In older patients, greater severity of DD was evident, suggesting that this condition may worsen with age during growth.

Step-back anterior repositioning splint retraction for temporomandibular joint disc displacement with reduction in adult patients.

Anterior repositioning splint (ARS) is used to treat temporomandibular joint (TMJ) disc displacement with reduction (DDwR). However, high recurrence rate remains a problem especially in patients with unstable occlusions. This study optimised standard ARS therapy and proposed a step-back ARS retraction (SAR) method in adult patients with DDwR. Dental examinations and magnetic resonance imaging of TMJ were obtained before treatment (T0), 1 to 3 months (T1), 3 to 6 months (T2) and 6 to 12 months (T3) during treatment in 48 adults (average age 27.1 ± 5.7 years). After 3 months of basic ARS wearing, personalised treatment for patients with normal disc-condyle relationship was prescribed depending on bilaminar zone adaptations and severity of molar openbite. SAR which required sequential ARS wearing was designed for patients with deep overbite/overjet until retrodiscal tissue adaptations and stable occlusions were achieved. The maximum interincisal opening was increased from 44.3 ± 6.9 to 45.3 ± 6.3 mm (p < .01), and joint pain was alleviated after ARS treatment. The overall success rate of ARS wearing was 92.1% (58/63) featured by a recaptured disc. Fifteen patients who underwent SAR therapy all showed bilaminar zone adaptations in the end, and one patient had positive condylar bone remodelling. ARS treatment could improve mouth opening and joint symptoms in adult DDwR patients. SAR method was suitable for treating DDwR patients with deep overbite and overjet and improved retrodiscal tissue adaptations and condylar bone remodelling.

Counselling treatment versus counselling associated with jaw exercises in patients with disc displacement with reduction—a single-blinded, randomized, controlled clinical trial

ObjectiveTo compare effectiveness of counselling program versus counselling program plus jaw exercises to reduce pain and click in patients with temporomandibular joint disc displacement with reduction (DDWR).Materials and methodsPatients were divided into two groups: instructions for temporomandibular disorders (TMD) plus jaw exercises (test, n = 34), only TMD instructions (control, n = 34). Pain was analyzed by palpation (RDC/TMD). It was investigated if the click caused discomfort. Both groups were evaluated at baseline, 24 h, 7 days, and 30 days’ post treatment.ResultsThe click was present in 85.7% (n = 60). In 30-day evaluation, there was a statistically significant difference between groups in the right median temporal muscle (p = 0.041); and there was a statistically significant difference in treatment self-perception (p = 0.002) and click’s discomfort (p < 0.001).ConclusionThe exercise with recommendations showed better results, resolution of the click, and self-perception of the treatment effectiveness.Clinical relevanceThis study presents therapeutic approaches that are easy to perform and that can be monitored remotely. In view of the current stage of the global pandemic, these treatment options become even more valid and useful.Clinical trial registerThis clinical trial was registered at Brazilian Clinical Trials Registry (ReBec) under protocol RBR-7t6ycp (http://www.ensaiosclinicos.gov.br/rg/RBR-7t6ycp/), Date of registration: 26/06/2020.

Clinical study of magnetic resonance imaging-based texture analysis and fasciculation of the lateral pterygoid muscle in young patients with temporomandibular disorder

We aimed to evaluate the effectiveness of clinical examination combined with texture analysis of magnetic resonance imaging (MRI) and fasciculation patterns of the lateral pterygoid muscle (LPM) in distinguishing among the different anatomic causes of temporomandibular disorder. We divided the patients into four groups: healthy control (HC), disk without displacement (DWoD), disk displacement with reduction (DDWR), and disk displacement without reduction (DDWoR). Demographic information and clinical symptoms of patients in each group were recorded. LPM textures were compared among groups. LPM fasciculation was examined. P<0.05 indicated significant difference. Several clinical symptoms and signs, but not age or sex, differed significantly among groups. Oblique sagittal planar MRI revealed significant differences in the parameters of Angular Second Moment, Contrast, Correlation, Inverse Difference Moment, and Entropy between the healthy controls and the 3 patient groups. MRI of the patients, both without and with disk displacement, demonstrated relative uniformity in gray distribution and correlation of gray values, with greater complexity but an unclear texture and no obvious regularity. The proportion of type B LPM fascicles was significantly higher in the DDWR and DDWoR groups CONCLUSION: Temporomandibular disorder, without and with disk displacement, is associated with clinical symptoms and texture analysis values that differ from healthy muscle. The types of LPM fascicles are related to the position of the articular disk.

Relationship between Mandibular Condyle Position and Pain in Patients with Disc Displacement with Reduction: A Retrospective Study

Objective: This study aimed to compare the condyle position of the temporomandibular joint (TMJ) in patients with disc displacement with reduction (DDWR) between with and without arthralgia using cone-beam computed tomography (CBCT). Methods: A total of 39 adult patients were examined retrospectively and were divided into three groups: 14 patients (21 joints) with TMJ DDWR and arthralgia, 14 patients (14 joints) with TMJ DDWR without arthralgia, and 11 asymptomatic patients (22 joints). Joint space measurements and condyle position were assessed using sagittal and coronal CBCT images. The radiographic data were correlated between the subgroups. One-Way ANOVA test was used for the analysis of normally distributed data, Kruskal Walis H test was used for non-normally distributed data in comparisons between three or more groups. The relationship between categorical data was examined with Chi-Square analysis. A descriptive statistical method (Mean, Median, Standard Deviation, Minimum-Maximum) was used while evaluating the study data. The confidence interval was set at 0.05 Results: There was no significant difference in age and gender between subgroups. The mean posterior and lateral joint space distance was found significantly higher in the painful DDWR group than in the painless DDWR group, and the incidence of anterior condylar position was significantly higher in the painful DDWR group than in the control group and painless DDWR group respectively. However, there was no significant difference in mediolateral condyle position variables among subgroups. Conclusion: Anterior condyle position may be correlated with pain in disc displacement disorders.

Stomatognathic Risk Factors and Clinical Manifestations of Temporomandibular Disorders in Indian Population: A Case-control Study.

This study was aimed to compare the risk factors and associated clinical manifestations of patients with temporomandibular disorders (TMDs) in the Indian population. A total of 52 patients were explored according to the Diagnostic Criteria for Temporomandibular Disorders (DC/TMD) and compared with 48 controls. The mean age of the study group was 30.96 ± 11.60 years, 41% were males and 59% were females. The mean age in the control group was 31.5 ± 9.9 years (37.5% males), measuring differences in TMD risk factors (self-perceived stress, parafunctions, occlusal interferences, history of orthodontic treatment, and/or extraction). The most common sign observed in the selected subjects was the joint sound (clicking) (42%), followed by mandibular deviation 39% as the second most common sign. Myofascial pain (MFP) (single or multiple diagnoses) was the most frequent diagnosis (n = 40, 76%), followed by disc displacement with reduction (DDWR) (32.1%), arthralgia (30%), and disc displacement without reduction (DDWoR) (7.6%). More than one DC/TMD diagnosis was established in 63.2% of the patients. The risk factors like presence of clenching, stress perception, parafunctions, tooth wear, and occlusal interferences were significantly more frequent in all the cases than in the respective controls. In the studied population, the presence of TMD was found to be positively related to factors namely female gender, parafunction, occlusal interferences, psychological stress, and tooth wear. Myofascial pain is the commonest diagnosis (either single or in combination). It is followed by DDWR (either single or in combination with others). Double diagnosis is also common. Temporomandibular disorders showed a female predilection and were found to be positively related to factors, viz., parafunction, occlusal interferences, stress, and tooth wear. Clinicians should also be aware of common clinical manifestations of TMDs and their related stomatognathic risk factors to provide comprehensive oral care and to identify such factors for disease prevention.

Does Temporomandibular Joint Magnetic Resonance Imaging Diagnosis Support Clinical Examination Diagnosis Following Diagnostic Criteria for Temporomandibular Disorders?

The Diagnostic Criteria for Temporomandibular Disorders (DC/TMD) has been validated as a clinical diagnostic guideline with high-sensitivity and -specificity in identifying TMDs. The purpose of this study was to evaluate the agreement between DC/TMD diagnoses and magnetic resonance imaging (MRI) diagnoses in patients with TMD. A prospective cohort study was conducted on patients with TMD. The predictor variable was the clinical diagnosis of TMD based on DC/TMD criteria. The outcome variable was the MRI diagnosis of TMD. The diagnoses used for both the predictor variable and the outcome variable were the same. They were normal, disc displacement with reduction (DDWR), DDWR with intermittent locking, disc displacement without reduction (DDWOR) with limited opening, DDWOR without limited opening, degenerative joint disease, and subluxation. Age and gender of the patients and number of joints evaluated were covariates. Each subject had clinical examination performed by two independent Oral and Maxillofacial Surgeons. All subjects had a bilateral temporomandibular joint (TMJ) MRI performed which was evaluated by a radiologist. The correlation between the clinical and MRI diagnoses was calculated using Cohen's kappa value with a P value of <.05 considered significant. A total of fifty patients (100 TMJs) were enrolled with 38 females and 12 males. The mean ages were 31.92 and 31.75years, respectively, with a total of 100 TMJs analyzed. Internal derangement was clinically identified in 76% of the joints and with MRI in 69% of joints. The Cohen's kappa value between DC/TMD and MRI diagnoses was found to be κ=0.720 (P<.01). The respective sensitivity and specificity in determining disc position clinically for DDWR was 1 and 0.96; for DDWR with intermittent locking 0.78 and 0.91; for DDWOR with limited opening 0.9 and 0.98; for DDWOR without limited opening 1 and 0.9; for degenerative joint disease 0.63 and 0.97 and for subluxation 0.28 and 1.00. The DC/TMD clinical examination performed well in all types of disc displacement but is less reliable than MRI in detecting the presence of degenerative disc diseases and subluxation.

Correlation Between the Masticatory Muscle Dimensions and Internal Derangement of Temporomandibular Joints Based on Magnetic Resonance Imaging

Background: Temporomandibular joint disorders (TMDs) are the most common cause of non-odontogenic pain in the maxillofacial region. Internal derangement (ID) is one of the most prevalent causes of TMDs, and disc displacement is recognized as the most common ID. The masticatory muscles are among anatomical structures involved in TMDs that may be affected by ID. Objectives: This study aimed to evaluate the correlation between the masticatory muscle dimensions and ID of temporomandibular joints using magnetic resonance imaging (MRI). Patients and Methods: This cross-sectional study was conducted on the MRI images of 145 patients, retrieved from the archives of the MRI diagnostic and research center during 2020 - 2021. The patients were categorized into three main groups of normal disc position (NP) (n = 42), disc displacement with reduction (DDR) (n = 54), and disc displacement without reduction (DDWR) (n = 49). The maximum width and height of the masseter and medial pterygoid muscles and the maximum height and length of the superior and inferior heads of the lateral pterygoid muscle were measured on MRI images for each of the groups. Data were analyzed using t-test, Pearson’s correlation test, ANOVA test, and Tukey’s test (alpha &lt; 0.05). Results: Significant differences were observed between the NP, DDR, and DDWR groups regarding the height (P &lt; 0.001) and length (P &lt; 0.001) of the superior head of the lateral pterygoid muscle; both parameters were significantly higher in the NP group, followed by the DDR and DDWR groups (P &lt; 0.05). The dimensions of masticatory muscles were significantly greater in males than females (P &lt; 0.05), except for the width of the medial pterygoid muscle (P = 0.064). The height of the masseter muscle (r = 0.190, P = 0.022) and the medial pterygoid muscle (r = 0.166, P = 0.046) was significantly correlated with age. Conclusion: Significant correlations were found between the height and length of the superior head of the lateral pterygoid muscle and ID of TMJ; the corresponding values were lower in the DDWR group compared to the DDR and NP groups, respectively.

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

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

Craniofacial Morphology of Temporomandibular Disorder Patients with Different Disc Positions: Stratifying Features Based on Sex and Sagittal Skeletal Pattern.

Disc displacement (DD) appears in the majority of temporomandibular disorder (TMD) patients. The correlation between craniofacial morphology and different disc positions has been underlined, while the craniofacial morphological differences based on sex and sagittal skeletal pattern stratification have been insufficiently studied. In this study, 304 patients with TMD complaints were included and classified into normal position, disc displacement with reduction (DDwR) and disc displacement without reduction (DDwoR) groups according to magnetic resonance imaging. A total of 24 cephalometric measurements, covering the cranial base, vertical relationship, sagittal relationship, mandible position and morphology, and dental relationship, were assessed using lateral cephalograms. A stratified analysis was performed based on the sex and sagittal skeletal pattern. Overall, DD patients had distinctive craniofacial morphological features. The posterior cranial base length and mandibular arc angle were statistically different only in females, while the Y-axis angle, occlusal plane angle and sella nasion point A angle (SNA) might be unique features in males. Skeletal class II had the most statistically different measurements compared to the others. Differences in the Frankfort mandibular incisor angle (FMIA) and saddle angle were especially displayed in skeletal class III patients. The sex and skeletal sagittal pattern could affect the morphological differences in TMD patients with different disc positions.

Observational study investigating the relationship between maxillomandibular characteristics and temporomandibular disc conditions in female patients with a skeletal class III pattern.

The objective of this study was to analyze the relationship between maxillomandibular characteristics and the severity of temporomandibular disc displacement in female patients with a skeletal class III (SKIII) pattern. Fifty-seven samples were included in the study. The evaluation of articular disc conditions was conducted using magnetic resonance imaging, while 25 cephalometric variables from lateral and postero-anterior (P-A) cephalograms were measured to determine their maxillomandibular characteristics. The samples were categorized into three groups based on the articular disc conditions: (1) normal disc position (NDP), (2) disc displacement with reduction (DDwR), and (3) disc displacement without reduction (DDwoR). The relationship between the maxillomandibular characteristics and disc conditions was examined through both basic statistical analysis and multivariate analysis using principal component analysis (PCA). The Kruskal-Wallis and Dunn-Bonferroni tests revealed a significant difference between the groups in terms of the deviation of mandibular characteristics observed on the P-A cephalogram. The DDwoR group exhibited significantly larger menton deviation, ramal height asymmetry index, and total mandibular length asymmetry index compared to the NDP and DDwR groups. Moreover, the PCA successfully extracted all cephalometric variables into eight principal components. Among them, only the principal component related to mandibular asymmetry was able to differentiate the SKIII samples with DDwoR from the other groups. The findings of this study highlight a significant relationship between mandibular asymmetry and the severity of disc displacement, particularly DDwoR, in female patients with a SKIII pattern.

Promising minimally invasive treatment modalities for symptomatic temporomandibular joint disc displacement with reduction: a randomized controlled clinical trial

BackgroundPain and clicking are the primary complaints in patients suffering from temporomandibular joint disc displacement with reduction (DDwR), negatively affecting the patients' quality of life, making the treatment essential. This prospective randomized controlled trial (RCT) was conducted to evaluate the effectiveness of botulinum toxin type-A (BTX-A) and low level laser therapy (LLLT) in comparison to anterior repositioning appliance (ARA) for the treatment of DDwR.MethodsA total of 27 patients were randomly allocated to 3 groups; ARA (control group), BTX-A, and LLLT; with 9 patients each. All patients were evaluated before and 3 months after the treatment using a visual analogue scale (VAS) and magnetic resonance imaging (MRI).ResultsAt 3 months follow-up, all groups showed a significant reduction in pain assessed by VAS (P = 0.007). Measured on MRI, there was a significant improvement in disc position and joint space index (JSI) in BTX-A group (P < 0.001, P = 0.011) and LLLT group (P = 0.002, P = 0.017) in comparison to the control group (P = 0.087, P = 0.066) respectively. As for time of recovery, a statistically significant difference was observed in BTX-A group (P < 0.001) and LLLT (P < 0.001) group in comparison to ARA group, which showed the most prolonged duration for reduction of DDwR symptoms.ConclusionWe concluded that BTX-A and LLLT could be considered effective alternative treatment modalities to ARA regarding reducing joint pain, clicking, and improving disc position in patients with symptomatic DDwR.Trial registrationThis prospective double-blinded RCT has been registered at ClinicalTrials.gov with identification number: NCT05194488, 18/1/2022.

The relationship of biochemical factors related to calcium metabolism with temporomandibular disorders

ObjectiveThe aim of this study is to investigate the relationship between calcium metabolism-related biochemical factors (alkaline phosphatase, vitamin D, parathyroid hormone (PTH), calcium, phosphorus and magnesium), and temporomandibular joint (TMJ) disk displacement with reduction (DDWR). Materials and MethodsThis prospective observational study included patients with temporomandibular disorders (TMDs) (n = 50) and healthy controls (n = 50) of similar age and sex. The diagnosis of TMJ DDWR was made using the diagnostic criteria for temporomandibular joint disorders (DC/TMD). Both groups were compared in terms of serum alkaline phosphatase, 25 (OH) vitamin D, PTH, calcium, magnesium, and phosphorus levels. P<0.005 was accepted as a significant difference. ResultsThere was no significant difference between the groups in terms of age, gender, and body mass index (BMI). Calcium levels of patients with TMD were statistically significantly lower than control patients (p<0.05). While there was no significant difference between the two groups in terms of mean VIT D, the number of people with severe Vit D deficiency (<10 ng) in the TMD group was significantly higher than in the control group (p<0.05). There was no statistically significant difference between the groups in terms of serum alkaline phosphatase, magnesium, phosphorus and PTH levels. ConclusionThe differences in serum calcium and vitamin D levels seen in the study indicate that biochemical factors related to calcium metabolism may be associated with TMJ DDWR. These results suggest that calcium and vitamin D deficiency should be evaluated and corrected in patients with TMD.

TMJ &amp; Its role in Prosthodontia: A Systematic Review

Aim The aim of this systematic review was to evaluate importance of TMJ and assessing the prevalence of temporomandibular joint disorders (TMJD) among the general population. Methodology Five main electronic databases and three grey literature were searched to identify observational studies in which TMJD was diagnosed using the research diagnostic criteria (RDC/TMD) or diagnostic criteria (DC/TMD). The studies were blindly selected by two reviewers based on eligibility criteria. Risk of bias (RoB) was assessed using the Joanna Briggs Institute Critical Appraisal Checklist, and the “R” Statistics software was used to perform meta-analyses. Results From 2741 articles, 21 were included. Ten studies were judged at low RoB, seven at moderate, and four at high. The TMJD investigated were as follows: arthralgia, disk displacement (DDs) with reduction (DDwR), DDwR with intermittent locking, DDs without reduction (DDwoR) with limited opening, DDwoR without limited opening, degenerative joint disease (DJD), osteoarthritis, osteoarthrosis, and subluxation. The main results from prevalence overall meta-analyses for adults/elderly are as follows: TMJD (31.1%), DDs (19.1%), and DJD (9.8%). Furthermore, for children/adolescents are as follows: TMJD (11.3%), DDs (8.3%), and DJD (0.4%). Considering the individual diagnosis meta-analyses, the most prevalent TMJD is DDwR for adults/elderly (25.9%) and children/adolescents (7.4%).

Preliminary MRI evaluation of anterior repositioning splint in treatment of disc displacement with reduction of temporomandibular joint

Objective: MRI images were used to study the efficacy of anterior repositioning splint (ARS) in the treatment of different types of disc displacement with reduction (DDWR) in temporomandibular joint. Methods: From September 2020 to December 2021, 26 patients with DDWR were enrolled in the Department of Oral and Maxillofacial Surgery, the First Affiliated Hospital of Zhengzhou University. There were 5 males and 21 females with an average age of (20.8±5.8) years. ARS was used for 3-6 months. The changes of joint clicking, opening type and joint pain before and after treatment were compared. The changes of disc position, disc-condyle angle and condylar bone mass before and after treatment were compared by MRI. Paired t-test was performed on the disc-condyle angle before and after treatment, Fisher's exact test was performed on the change of disk position, and other count data were expressed as rate (%). Results: After ARS treatment, the effective rates of joint clicking,abnormal opening, joint pain and disc displacement were 97%(35/36), 14/18, 7/9 and 95%(36/38). MRI analysis found that there was a significant difference between the disc position before and after treatment (P<0.001), MRI analysis showed that the anterior disc displacement (48%, 25/52) and the anterolateral disc displacement (17%, 9/52) were the most common before treatment. In contrast, the normal superior disc (75%, 39/52) and the anterior disc displacement (17%, 9/52) were the most common after treatment, no significant changes were seen after treatment in the anteromedial disc displacement. The disc-condylar angle was (36.09±19.02) ° before ARS treatment and (3.94±10.12) ° after ARS treatment(t=9.23, P<0.001). After treatment, 46% (12/16) of the patients showed new bone formation, and the height of the condyle recovered. Conclusions: The clinical efficacy of ARS in the treatment of anterior disc displacement and anterolateral displacement of temporomandibular joint is remarkable, which can restore the disc-condylar relationship of most patients with indications.