Temporomandibular Disorders: "Occlusion" Matters!

Fully digital workflow of occlusal reconstruction treatment in a patient with congenital dentition defects

OBJECTIVE

Occlusal reconstruction is a critical intervention for patients with dental hard tissue defects, temporomandibular joint (TMJ) disorders, and jaw position abnormalities. Clinical efficiency and outcomes of these procedures have improved with advances in digital technologies. This case report aims to illustrate a comprehensive digital workflow for occlusal reconstruction in a patient with congenital dentition defects, emphasizing the application of digital technologies to enhance treatment outcomes.

CLINICAL CONSIDERATIONS

A 28-year-old woman with previously installed porcelain-fused-to-metal bridge restorations presented with a fractured prosthesis and TMJ symptoms. A multidisciplinary approach was adopted involving the use of digital facebow, intraoral scanners, digital smile design, and CAD/CAM technologies. The process included the extraction of defective restorations, temporary restorations to refine jaw position, and final permanent restorations. The digital workflow facilitated precise diagnostics and treatment, culminating in the successful installation of permanent restorations. Regular follow-ups at one- and three-months post-treatment confirmed stable occlusal function and high patient satisfaction.

CONCLUSIONS

This case report showcases the potential of multiple digital technologies to streamline complex dental treatments and achieve high-quality results.

CLINICAL SIGNIFICANCE

The integration of digital technologies in occlusal reconstruction treatments offers significant benefits in terms of precision, patient comfort, and esthetic outcomes.

Temporomandibular joint dysfunction in relation to tinnitus in Peruvian patients: A cross-sectional study

Background

To determine the relationship between temporomandibular joint dysfunction (TMJD) and tinnitus in Peruvian adult patients.

Material and Methods

This observational and cross-sectional study was conducted between April and May 2023, including 76 adult patients from the Otorhinolaryngology Service of Víctor Lazarte Echegaray Essalud Hospital in Trujillo (Peru). The intra- and inter-rater reliability was determined for the clinical measurement of TMJD, obtaining Kappa values above 0.995. To diagnose tinnitus, we worked with a doctor specializing in otolaryngology. Chi-square test and logistic regression were used to analyze results, considering a significance level of p<0.05.

Results

A relationship was found between TMJD and tinnitus (p=0.022), increasing the frequency of this disorder as temporomandibular involvement was higher (p=0.043). There was no relation between these disorders according to gender and age, nor in hypertensive patients (p=0.131) or patients suffering from migraine (p=0.147); however, a relationship was found between TMJD and tinnitus in patients with hearing loss (p=0.046).

Conclusions

TMJD is associated with tinnitus in otorhinolaryngological and hypoacusis patients. However, in hypertensive and migraine patients, and according to gender and age, no relation was found between those disorders. Key words:Tinnitus, Temporomandibular Joint Disorders, Hearing Loss, Sensorineural, Audiometry, Migraine, Hypertension, Headache.

Pharmacological therapy in the management of temporomandibular disorders and orofacial pain: a systematic review and meta-analysis

BACKGROUND

Temporomandibular disorders (TMD) are manifested by soreness in the jaw joint area and jaw muscles, clicks or creaks when opening or closing the mouth. All these symptoms can be disabling and occur during chewing and when the patient yawns or speaks. Several classes of drugs are used to treat symptoms. This review aims to assess which drug suits the different signs.

METHODS

Pubmed, Web of Science and Lilacs were systematically searched until 01/02/2023. Clinical trials were selected that dealt with drugs used in temporomandibular dysfunction RESULTS: Out of 830 papers, eight studies were included. The Meta-Analysis with Continuous Outcomes with Pre-Calculated Effect Sizes resulted in the rejection that there is intergroup variability (p.0.74).

CONCLUSIONS

Treatment of orofacial pain is still a significant challenge for dentistry. We can conclude that there is no drug of first choice in the treatment of temporomandibular pain. However, the clinician must distinguish the type of pain and the aetioloic cause of the pain so that the patient can be treated and managed pharmacologically.

Acute dental malocclusion associated with lateral pterygoid muscle partial tear: Case Report and literature review

BACKGROUND

The article presents a rare case of acute malocclusion produced by a unilateral partial tear of the lateral pterygoid muscle and an up-to-date literature review of the pathology.

CLINICAL PRESENTATION

A 37-year-old female was examined; her chief complaints were pain on the right side of the temporomandibular joint (TMJ) area and mastication impairment associated with major occlusal modifications and anterior open bite. After magnetic resonance imaging (MRI) and cone beam computed tomography (CBCT) of the TMJ and subsequent MRI for soft tissue, the final diagnosis was a partial right lateral pterygoid muscle tear.

CONCLUSION

The case shows the value of combined imaging in temporomandibular disorders (TMD) and the importance of soft tissue evaluation in addition to articular examination, as the primary pathology might lie outside the joint. The authors' review of the current literature did not hitherto reveal a similar case.

[Comparative evaluation of the accuracy of 3D TMJ analysis performed by different methods of processing computed tomograms]

OBJECTIVE

The aim of this study. Comparison of the accuracy of segmentation of TMJ elements in different ways and assessment of the suitability of the data obtained for the diagnosis of TMJ dysfunction.

MATERIALS AND METHODS

To study the segmentation of the bone elements of the TMJ (articular fossa, head of the LF), 60 computed tomograms of the maxillofacial region of patients were randomly selected in various ways (archival material). In group 1, the results of CT processing by AI diagnostics algorithms (Russia) were collected; in group 2, the results of CT processing based on the semi-automatic segmentation method in the Avantis3D program. The results of CT processing by Avantis3D AI algorithms (Russia) with different probability modes - 0.4 and 0.9, respectively, were selected for the third and fourth groups. Visually, the coincidence of the contours of the LF heads and articular pits isolated using different methods with their contours on all possible sections of the original CT itself was evaluated. The time spent on TMJ segmentation according to CT data was determined and compared using the methods described above.

RESULTS

Of the 240 objects, only 7.5% of the cases showed a slight discrepancy between the contours of the original CT in group b1, which was the lowest of all. A slight discrepancy in the TMJ contours to be corrected is characteristic of the semi-automatic method of segmentation by optical density was detected in 50.4% (group 2). The largest percentage of significant errors not subject to correction was noted in the first group, which made it impossible to perform a full 3D analysis of the TMJ, and the smallest in the second and fourth. The magnitude of the error in determining the width of the articular gap in different groups is comparable to the size of one voxel per CT. When segmentation is carried out using AI, the difference between segmented objects is close to zero values. The average time spent on TMJ segmentation in group 1 was 10.2±1.23 seconds, in group 2 - 12.6±1.87 seconds, in groups 3 and 4 - 0.46±0.12 seconds and 0.46±0.13 seconds, respectively.

CONCLUSION

The developed automated method for segmenting TMJ elements using AI is obviously more suitable for practical work, since it requires minimal time, and is almost as accurate as other methods under consideration.

Effects of occlusal conditions on masseter and temporalis muscle activity: An electromyographic evaluation

Introduction

Dental occlusion contributes to the development of temporomandibular disorder.

Objective

This case control study examined the influence of different occlusal conditions on the surface electromyography (sEMG) of the superficial part of the masseter muscle (MM) and anterior part of the temporalis muscle (TA) during clenching in the maximum intercuspal position (MIP).

Materials and methods

Twelve healthy subjects had their anterior, right posterior, or left posterior teeth added by composite resin to generate the bilateral posterior, unilateral left, or unilateral right posterior tooth losses, respectively. Muscle activity in the resting stage, MM's and TA's maximum voluntary clenching (MVC; µV) in MIP, each muscle activity's symmetry (%), and ipsilateral MM and TA synergy (%) were measured by sEMG. All parameters were analyzed by SPSS version 23.0, and the significance level was set at p < 0.05.

Results

The MM's and TA's sEMG activity at the resting stage significantly differed from those at the other occlusal conditions (p < 0.05). Both muscles' MVC were highest at the MIP during clenching but lowest during anterior clenching. During unilateral posterior clenching, such MVC was higher at the occluding than at the non-occluding sides. The TA's symmetry during clenching at the anterior and unilateral posterior teeth was lower than that at the MIP during clenching. No significant difference was seen in the ipsilateral MM and TA synergy.

Conclusion

Different occlusal conditions influenced the MM's and TA's sEMG activity. Each masticatory muscle responded differently to the same occlusal conditions.

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

BACKGROUND

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

METHODS

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

RESULTS

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

CONCLUSION

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

Effect of physiotherapeutic procedures on the bioelectric activity of the masseter muscle and the range of motion of the temporomandibular joints in the female population with chronic pain: a randomized controlled trial

INTRODUCTION

Physical therapy (PT) methods applied in dentistry are increasingly discussed nowadays. Taking into account a rapidly growing number of temporomandibular disorders (TMDs) and orofacial pain patients, it is reasonable to determine which of the available physiotherapeutic (PT) methods are more effective than others, especially in terms of their possible analgesic and myorelaxant effects.

OBJECTIVE

To assess manual and physical factors influencing pain reduction or elimination and increased muscle tension in patients with TMD; yet the influence of the applied forms of PT on the range of motion (ROM) of temporomandibular joints (TMJ).

MATERIAL AND METHODS

A randomized, parallel-group, RCT, single-blind, equi-randomized (1:1) study was conducted in DC/TMD Group Ib patients (20-45 years of age). An experimental group (G1, n = 104) and a control group without TMD (G2, n = 104) were created according to CONSORT guidelines. Diagnostic measurements were performed in both groups (mass sEMG, temporomandibular joint range of motion-ROM, pain intensity - NRS). Group G1 was randomly divided (envelope method) into 4 therapeutic groups, in which therapy was carried out for 10 days: magnetostimulation (MS), magnetoledotherapy (MLE), magnetolaserotherapy (MLA), manual therapy (MT). Each time after the therapy, ROM and NRS measurements were performed, and after the 5th and 10th day sEMG.

RESULTS

Statistically significant differences were found in the sEMG values of the masseter muscles, TMJ ROM and the pain intensity in G1 and G2 (p < 0.00). The largest decrease in sEMG (% MVC) of the masseter muscle occurred in the subgroup in which the manual therapy (MT) procedures were applied, p < 0.000. There was no clinically significant difference in and between other subgroups. There was a distinct mandible ROM increase noted in the MT group, with minimal changes in the MLA and MLE groups and no changes in the MS group. There was a clear increase in the lateral mobility of both right and left TMJ in the MT group. There were no differences in the course of the study in the MS group, and slight increases in the MLA and MLE groups. In the case of pain measurements, the greatest decrease in pain intensity was observed in the MT subgroup.

CONCLUSIONS

According to our results manual therapy is an effective form of treatment in patients with pain, increased masticatory muscle tension and limitation in mandible ROM. Dental physiotherapy should become an integral part of multimodal TMD patients' treatment.

Orthodontics and Temporomandibular Disorders: An Overview

The relationship between orthodontics and temporomandibular disorders (TMDs) constitutes a subject of paramount significance in dental and craniofacial health. This abstract embarks upon an in-depth examination of the intricate connection between orthodontic practices and TMD, primarily focusing on evaluating the impact of orthodontic treatment modalities on the health and functionality of the temporomandibular joint (TMJ). This exploration elucidates the multifaceted interplay between orthodontic interventions and TMD by traversing a landscape of scholarly research and empirical investigations. The review draws from a broad spectrum of studies to analyze the potential influence of orthodontic treatments, which encompass occlusal adjustments and alterations in jaw positioning, on the development and management of TMD symptoms. The inquiry delves into the diverse range of TMD conditions, considering the implications of orthodontic techniques on occlusal stability, condylar alignment, and overall TMJ function. Through a comprehensive synthesis of the available body of knowledge, this abstract aspires to equip dental practitioners, orthodontists, and researchers with a nuanced understanding of the complex dynamics that govern the relationship between orthodontics and TMD. This knowledge, in turn, offers a foundation for informed clinical decision-making and the formulation of effective treatment strategies for patients presenting with TMD symptoms. By shedding light on the intricate interactions between orthodontic procedures and TMJ health, this abstract contributes to the advancement of clinical practices, promoting improved patient outcomes and well-being in the context of both orthodontics and TMDs.

Bibliometric Analysis of Research on Temporomandibular Joint and Occlusion from 2000 to 2022

Purpose

This study conducted a bibliometric analysis that comprehensively described publications on temporomandibular joint and occlusion from 1 January 2000 to 31 October 2022, aiming to reveal hotspots and predict future research trends.

Methods

A total of 2985 articles and reviews were retrieved from Web of Science Core Collection (WoSCC). Excel 2019, VOSviewer and CiteSpace software were used for visualizing analysis of research trends, authors, journals, institutions, countries, keywords and cited references.

Results

Both the annual publication counts and citation times increased significantly. Wang MQ was the most active author. Moreover, Manfredini D and Okeson JP were the most influential two. Journal of Oral Rehabilitation was the core journal. University of Sao Paulo was the most productive institutions. "Temporomandibular disorders" (TMDs), "temporomandibular joint" and "occlusion" were the top 3 keywords with the most frequencies. Keywords and references with burst showed that the causes of TMDs, diagnosis and treatments for TMDs as well as bruxism may be hotspots currently and in the future.

Conclusion

In this study, the research trends, the most productive and influential authors, journals, institutions, countries, in addition to keywords and cited references with burst in the field of temporomandibular joint and occlusion were revealed by a bibliometric analysis, which could help scholars to understand recent hotspots and future trends.

Intraoral occlusal adjustment time and volume required for CAD/CAM crowns fabricated with different virtual mounting methods (A randomized crossover trial)

OBJECTIVE

To measure the required clinical time and volume of occlusal adjustment when the maxillary cast is positioned in a virtual articulator using one of three methods: digitization of a facebow-mounted mechanical articulator (group A), virtual Bonwill triangle (group B) or a 3D face scan (group F).

MATERIALS AND METHODS

In this randomized, triple-blind, crossover trial; 11 participants were enrolled. Every participant had one molar indicated for a single crown restoration. Three crowns were designed and milled for every participant molar totaling 33 crowns. Each of the three crowns was fabricated with the participant's casts virtually mounted utilizing a different method. An impression was taken of the crown in place before occlusal adjustment. The occlusal adjustment was then performed and timed with the three crowns in the different groups. After the occlusal adjustment, an impression of the adjusted crown was taken. The pre-adjustment and post-adjustment impressions were digitally superimposed and the volume difference was measured. The Kruskal-Wallis test was used to compare the groups.

RESULTS

Group A showed the shortest mean adjustment time (3:44.59 ± 3:39.07) followed by group F (4:30.09 ± 2:01.50) and group B (4:35.30 ± 2:32.33). The mean adjustment volume for group A was (28 ± 19.1 mm³) followed by group F (30.5 ± 18.8 mm³) and group B (40.6 ± 29.5 mm³). Different virtual mounting methods had no statistically significant effect on adjustment time (P-value = 0.538) or adjustment volume (P-value = 0.490).

CONCLUSIONS

A simplified approach in virtual articulator mounting appears to be justified in the construction of a single full-coverage prosthesis. Added labor, time and cost of more elaborate virtual mounting methods seem to be counterproductive.

Association between Condylar Bone Changes and Eichner Index in Patients with Temporomandibular Dysfunction: A Cone Beam Computed Tomography Study

STATEMENT OF THE PROBLEM

Eichner index is a dental index, which is based on the occlusal contacts between naturally existing teeth in premolar and molar regions. One controversial topic is the association between occlusal status and temporomandibular joint dysfunction (TMD) and its associated degenerative bony changes.

PURPOSE

Through the use of cone-beam computer tomography (CBCT), the current study sought to ascertain the relationship between the Eichner index and condylar bone alterations in TMD patients.

MATERIALS AND METHOD

In this retrospective study, the CBCT images of bilateral temporomandibular joints (TMJs) of 107 patients with TMD were evaluated. The patients' dentition was classified into three groups of A (71%), B (18.7%), and C (10.3%), according to the Eichner index. Radiographic indicators of condylar bone alterations, including as flattening, erosion, osteophytes, marginal sclerosis, subchondral sclerosis, and joint mice, were either present or absent and registered as 1 or 0, respectively. Chi-square test was used to evaluate the link between the condylar bony changes and the Eichner groups.

RESULTS

According to the Eichner index, the most prevalent group was group "A". The most prevalent radiographic finding was "flattening of the condyles" (58%). Condylar bony changes were found to be statistically related to age (p= 0.00). However, no significant relationship was found between sex and condylar bony changes (p= 0.80). There was a significant relationship between the Eichner index and condylar bony changes (p= 0.05).

CONCLUSION

Patients with greater loss of tooth supporting zones have more condylar bony changes.

Identification of crucial salivary proteins/genes and pathways involved in pathogenesis of temporomandibular disorders

Temporomandibular disorder (TMD) is a collective term for a group of conditions that lead to impairment of the function of the temporomandibular joint. The proteins/genes and signaling pathways associated with TMD are still poorly understood. The aim of this study was to identify key differentially expressed salivary proteins/genes (DEGs) associated with TMD progression using LC-MS/MS coupled with a bioinformatics approach. The protein–protein interaction network was obtained from the STRING database and the hub genes were identified using Cytoscape including cytoHubba and MCODE plug-ins. In addition, enrichment of gene ontology functions and the Reactome signaling pathway was performed. A total of 140 proteins/genes were differentially expressed. From cluster analysis, a set of 20 hub genes were significantly modulated: ALB, APOA1, B2M, C3, CAT, CLU, CTSD, ENO1, GSN, HBB, HP, HSPA8, LTF, LYZ, MMP9, S100A9, SERPINA1, TF, TPI1, and TXN. Two enriched signaling pathways, glycolysis and gluconeogenesis, and tryptophan signaling pathway involving the hub genes CAT, ENO1, and TPI1 have been identified. The rest of the hub genes were mainly enriched in the innate immune system and antimicrobial peptides signaling pathways. In summary, hub DEGs and the signaling pathways identified here have elucidated the molecular mechanisms of TMD pathogenesis.

Effects of Contact Sports on Temporomandibular Disorders: An Observational Study

The study investigated the prevalence of temporomandibular disorders in 100 competitive athletes in contact sports, equally grouped by the practiced game: Soccer (SoG), Rugby (RG), American Football (AFG), Boxing (BoG), Basketball (BaG), compared to a randomly control group of 20 non-athletes (CG). Symptoms and signs were examined according to the standardized Diagnostic Criteria for Temporomandibular Disorders through a questionnaire and clinical evaluation. Arthralgia showed significant differences between RG and CG and between AFG and CG (p < 0.05). Study groups reported masticatory muscle pain during function, neck and shoulder pain more frequently than CG, except for BoG. Closing click was significantly more present in study groups than CG, while crepitation was significantly higher only in RG and AFG. The deviation was wider in SoG, RG and AFG compared to CG (p < 0.05). Tukey’s multiple comparisons test showed a statistically significant reduction in right laterotrusion in RG vs. CG (p < 0.05); the comparison showed a decrease in right laterotrusion in RG vs. SoG and BoG (p < 0.05), a decrease in endfeel in RG vs. CG, BaG and AFG (p < 0.05). The data seem to support a relationship between the prevalence of TMD symptoms and signs in competitive athletes in contact sports, especially in RG and AFG compared to CG.

Does simultaneous versus individual-arch at-home dental bleaching regimen influence patient satisfaction? A randomized clinical trial

OBJECTIVE

Our randomized, parallel and single-blinded clinical trial evaluated patient level of discomfort during at-home bleaching testing the equivalence between two different protocols for the use of bleaching trays (simultaneous vs. single arch), as well as tooth sensitivity (TS), gingival irritation, (GI) and bleaching efficacy (BE).

MATERIALS AND METHODS

We randomized 100 patients into: simultaneous (n = 50) and single arch (n = 50). At-home bleaching was performed with 10% hydrogen peroxide (HP) for 2 weeks for simultaneous group and 4 weeks for single arch group. We assessed patient level of discomfort using 9-item questionnaire. The TS and GI, as well as BE using spectrophotometer and color guide were assessed using the visual analog scale (0-10). Data from level of discomfort and BE were evaluated by Student's t test. The TS and GI were compared using the relative risk and confidence interval (α = 0.05).

RESULTS

Only tray adaptation showed a significant effect after the second week (p < 0.002). There was equivalence between groups for level of discomfort (p < 0.01). We found no significant intergroup differences for the risk of TS or GI, nor for intensity. We observed no significant differences between them regarding bleaching efficacy (p > 0.21).

CONCLUSIONS

A simultaneous-use protocol for customized at-home dental bleaching trays proved to be equivalent to using single arch for patient level of discomfort and bleaching efficacy, with no significant increase in adverse effects.

CLINICAL SIGNIFICANCE

Clinicians may decide whether to use a simultaneous or single arch protocol for tray usage; however, bleaching was achieved more quickly when the trays were worn simultaneously.

Effect of Rehabilitation of Completely Edentulous Patients With Complete Dentures on Temporomandibular Disorders: A Systematic Review

The present study evaluates the effect of rehabilitating completely edentulous patients with complete denture prosthesis on temporomandibular disorders (TMD). The Preferred Reporting Items for Systematic Reviews and Meta-Analyses (PRISMA) standards were used to perform this systematic review, primarily to describe the technique. Manuscripts published between 1965 and December 31, 2021, were searched in the two most common electronic databases, PubMed and Cochrane Library. To find relevant scientific papers on the influence of complete dentures on temporomandibular disorders, an electronic pursuit of peer-reviewed articles confined to the English language and a dental survey were undertaken. Two observers reviewed the abstracts separately and chose five full-text papers that met the inclusion requirements. Due to the heterogeneity of the data provided, a meta-analysis could not be performed. The result of complete dentures on temporomandibular problems was studied in detail in five peer-reviewed papers. The result of the present study concluded that the complete denture could act as a conducive treatment option to the revocation of TMD for elderly edentulous patients. 

Necroptotic TNFα-Syndecan 4-TNFα Vicious Cycle as a Therapeutic Target for Preventing Temporomandibular Joint Osteoarthritis

Temporomandibular joint osteoarthritis (TMJOA) is a chronic degenerative disease for which the underlying mechanism still remains unclear. Compared with apoptosis and autophagy, necroptosis causes greater harm to tissue homeostasis by releasing damage-associated molecular patterns (DAMPs). However, the role of necroptosis and downstream key DAMPs in TMJOA is unknown. Here, rodent models of TMJOA were established by the unilateral anterior crossbite (UAC). Transmission electron microscopy (TEM) and immunohistochemistry of receptor interacting protein kinase 3 (RIPK3)/phosphorylation of mixed lineage kinase domain-like protein (pMLKL) were conducted to evaluate the occurrence of necroptosis in vivo. The therapeutic effects of blocking necroptosis were achieved by intra-articularly injecting RIPK3 or MLKL inhibitors and using RIPK3 or MLKL knockout mice. In vitro necroptosis of condylar chondrocyte was induced by combination of tumor necrosis factor alpha (TNFα), second mitochondria-derived activator of caspases (SMAC) mimetics and carbobenzoxy-valyl-alanyl-aspartyl-[O-methyl]- fluoromethylketone (z-VAD-fmk). The possible DAMPs released by necroptotic chondrocytes were screened by quantitative proteomics and blocked by specific antibody. Translucent cytosol, swollen organelles, and ruptured cell membranes, features of necroptosis, were frequently manifested in chondrocytes at the early stage of condylar cartilage degeneration in TMJOA, which was accompanied by upregulation of RIPK3/pMLKL. Inhibiting or knocking out RIPK3/MLKL significantly prevented cartilage degeneration. DAMPs released by necroptotic condylar chondrocytes, such as syndecan 4 (SDC4) and heat shock protein 90 (HSP90), were verified. Furthermore, blocking the function of SDC4 significantly attenuated the expression of TNFα in cartilage and synovium, and accordingly increased cartilage thickness and reduced synovial inflammation. Thus, the necroptotic vicious cycle of TNFα-SDC4-TNFα contributes to cartilage degeneration and synovitis, and can serve as a potential therapeutic target for treating TMJOA. © 2022 American Society for Bone and Mineral Research (ASBMR).

Occlusal Indicators Used in Dental Practice: A Survey Study

Introduction

The function of the masticatory apparatus is complete when the dentition is intact with contact between the individual teeth and proper occlusion with the antagonists. For years, occlusal contacts have been studied to determine their exact location and describing various materials and methods for their registration such as paper foil, silk, and Shimstock foil. For years, occlusal contacts have been studied to determine their exact location and describe various materials and methods for their registration such as paper foil, silk, shim stock foil, the T-Scan system, and more recently the OccluSense system. The primary aim of the study was at evaluating which of the occlusal indicators is the most commonly used in practice, and the secondary aim was whether dentists are willing to use digital methods to examine occlusion.

Materials and Methods

The main primary information of the survey was collected by sending electronically anonymous questionnaires to 2014 dentists, randomly selected from all regions of the country. 228 questionnaires were filled in and returned. To achieve the goal of the study, the self-developed questionnaire was created and tested to survey the opinion about the use of occlusal indicators in dental practice. Each questionnaire contains questions about the sociodemographic and professional status of the people in the group and their opinion about the positives and negatives and the effectiveness of occlusal indicators.

Results

The obtained results confirm the statement that the most frequently used occlusal indicator in dental practice is the articulation paper. Articulation foil and silk are used less frequently than articulation paper. Of the listed quality indicators, Shimstock foil is rarely used in practice. Of the indicated quantitative indicators, the T-Scan system is more used than the OccluSense system. In the era of rapid technology development, the opinion and desire of dentists to increasingly want to introduce in their clinical practice quantitative methods are the digital diagnosis of occlusion.

Conclusion

In any dental practice, if technically possible, digital methods would be used, giving more accurate and reliable data on the registered occlusal contacts.

Relationship between Clinical Symptoms and Magnetic Resonance Imaging in Temporomandibular Disorder (TMD) Patients Utilizing the Piper MRI Diagnostic System

Clinical problems of the temporomandibular joint (TMJ) and the masticatory musculature are both included in the term temporomandibular disorder (TMD). The purpose of the present study was to examine the pathology of the joints of patients diagnosed with TMD utilizing the dedicated Piper MRI-based classification, and to link these pathologies with various symptoms while considering their severity. In total, 64 patients with clinical TMD were examined. Symptoms were recorded using a questionnaire. The clinical examination included diagnosing the occlusion in centric relation, which was followed by a standardized MRI. It was confirmed that, although they occurred in a high percentage in all classes, muscle pain and occlusal interference are not indicators of TMJ damage. The results indicate that the progressive degradation of the TMJ, represented by qualification to the higher Piper classes, is associated with an increase in TMJ pain only up to a certain stage. For the highest Piper classes, the joint pain occurs in a smaller percentage of patients, but sounds are more frequent.

Association between temporomandibular disorders with clinical and sociodemographic features: An observational study

BACKGROUND

Temporomandibular disorders (TMD) are the most common orofacial impairment, but the relevance of certain clinical features in TMD is not clear.

OBJECTIVE

The main objective of this study was to analyse if temporomandibular disorders (TMD) are associated with sociodemographic (eg age, height, weight, body mass index and gender), psychological (eg anxiety and depression) and clinical features (eg use of dental splints, orthodontics, retainers, bruxism, sleep disturbance, familiar prior history of TMD and dental occlusion).

METHODS

An observational study was conducted to calculate the correlation of TMD, as assessed with DC/TMD criteria, with sociodemographic, psychological and clinical features on 59 voluntary subjects with TMD (n = 45) and without TMD (n = 14). Sex, height, weight, body mass index, age, use of dental splint, orthodontics, retainers, parafunctional disorders, sleep disturbance, familiar history of TMD, bruxism, anxiety, stress and dental occlusion class data were included in a multivariable correlation analysis to determine which variables are associated with TMD and bruxism.

RESULTS

TMD was found to be correlated with none of the features assessed (P > .05), but a negative correlation with the use of dental splint (P < .05). Dental occlusion class showed no statistically significant correlation with any assessed feature (P > .05).

CONCLUSION

The etiology of TMD is not clear and considering certain clinical features including dental occlusion are not justified in the evidence-based TMD practice for making irreversible occlusal treatment decisions.

Identification of Biomechanical Properties of Temporomandibular Discs

Material

Experimental and model tests were conducted on ten fresh porcine temporomandibular joint discs. The average thickness of disc tissue was, accordingly, 2.77 mm for the anterior zone, 3.98 mm for the posterior, and 1.54 mm for the intermediate. The selection of research material in the form of porcine discs was due to the similarity to human discs.

Methods

Discs were loaded in cycles, a temporary course with the amplitude 3 N and frequency 0.07 Hz, and growth in the load was 1 N/s. The selection of load frequency was due to real conditions of temporomandibular joint functioning during mastication. The necessary experimental research was conducted on a testing machine with a measurement range of 2.5 kN.

Results

The obtained numeric calculation results indicate that the number of load cycles has a decisive impact on the limitation of energy dispersion capacity through disc tissue. This phenomenon was observed in all the studies on the disc areas. Along with the growth in load cycles, discs are stiffened, and the most significant stiffness was observed in the intermediate area.

Conclusions

Based on the conducted research, it should be concluded that excessive load affecting temporomandibular joints caused by the act of mastication and occlusal forces generated during parafunction and in people with defined long-term bruxism has crucial importance on biomechanical disc properties and hence the course of temporomandibular joint conditions.

Fabricating a screw-retained, complete arch, fixed implant prosthesis using selective metal laser sintering: A clinical report

In contemporary prosthodontic practice, implant-supported therapy has consistently resulted in high success rates, with satisfactory and predictable outcomes for completely edentulous patients. Of the several options, complete-arch, fixed screw-retained solutions are generally considered to be the preferred treatment solution. Screw retention offers advantages such as predictable retrievability and potentially easy prosthodontic maintenance, as well as excess cement not being a concern. However, implant mispositioning and malalignment may often necessitate the use of cement-retained prostheses. This clinical report describes a method of fabricating a complete-arch, implant screw-retained, double framework metal-ceramic prosthesis, despite the unfavorable implant positioning, by using selective direct metal laser sintering technology.

Signos y síntomas asociados a trastornos temporomandibulares en niños y adolescentes. Cali, Colombia

Los trastornos temporomandibulares (TTM) en pacientes pediátricos se han estudiado poco. Realizar un diagnóstico oportuno, hace que exista mayor interés por parte de los investigadores para orientar a los odontólogos. El objetivo del estudio fue identificar la presencia de trastornos temporomandibulares registrados en las historias clínicas de pacientes atendidos en la clínica de Odontopediatría de la Universidad del Valle. Se realizó un estudio observacional descriptivo y transversal para evaluar presencia de trastornos temporomandibulares en pacientes, en edades entre 4 a 14 años, que asistieron a las clínicas de Odontopediatría de la Universidad del Valle (Cali-Colombia), durante 2013 y 2016. Se revisaron, 712 historias; 56% de sexo masculino y 44% de  sexo femenino. El 18,11% reportaron la presencia de al menos. Los signos y síntomas asociados con los TTM, los más frecuentes fueron el click bilateral (36,4%), la desviación y deflexión mandibular (27,1%) y dolor a la palpación (24,0%). La subluxación (1,6%) y el chasquido articular en apertura (0,8%) fueron los de menor presencia. Se concluyó que los trastornos de la ATM cada vez son mayores, es importante, realizar investigaciones que involucren los factores de riesgo y/o desencadenantes, la intervención oportuna y el manejo multidisciplinario de esta alteración. 

Temporomandibular disorders: improving outcomes using a multidisciplinary approach

Patients with temporomandibular disorders (TMD) can become very complex. This article aims to highlight the importance of the multimodal and multidisciplinary approach in this type of patients to improve clinical outcomes. At present we have innumerable techniques and tools to approach this type of patients from a biopsychosocial model where active and adaptive type treatments are fundamental. There are various health professions that have competence in the treatment of TMD, however, although in the most complex cases should be treated simultaneously, still too many patients receive unique treatments and only from one point of view. This review exposes the treatments available from a clinical-scientific perspective and also emphasizes the importance of working in specialized units with those professionals who have competencies on the different conditions that may occur.

[Assessment of postural control and balance in persons with temporomandibular disorders: A systematic review]

The stomatognathic system is the anatomo-functional unit of the cranio-cervico-facial region. Some dysfunctions affect its motor control. The aim of this study was to analyse the clinical usefulness of the various scales and instruments used in the assessment of postural control in people with temporomandibular disorders. A systematic review was carried out by 2independent reviewers in the PubMed, Medline, Ebsco, Science Direct and PEDro databases, selecting observational studies published between January 2006 and March 2017. The risk of bias and methodological quality was analysed following Cochrane indications and the Downs and Black quality scale. Ten studies were included, of which 9used computerised platforms, one added photogrammetry and one used electromyography. Seven studies were classified as moderate quality and 3as low quality. Posturography was the most widely used assessment instrument. Methodological differences did not allow determination of their clinical implications or the relationship between balance and the presence of temporomandibular disorders.