Temporomandibular joint diagnostics using CBCT

Three-Dimensional Changes of Condylar Position After Bimaxillary Surgery to Correct Skeletal III Malocclusion: Cone Beam Computed Tomography Voxel-Based Superimposition Analysis

BACKGROUND

The stability of the condylar position within the first 3 months after orthognathic surgery in patients with skeletal Class III malocclusion is crucial for subsequent orthodontic treatment.

PURPOSE

The purpose was to compare condylar positional changes 3 months after bimaxillary surgery to correct skeletal Class III deformities, utilizing the conventional two-dimensional combined with cone beam computed tomography voxel-based superimposition analysis.

STUDY DESIGN, SETTING, SAMPLE

This retrospective cohort study included skeletal Class III patients undergoing bimaxillary orthognathic surgery at Khon Kaen University, Thailand, in 2020. Exclusion criteria were patients with temporomandibular disorder symptoms, facial asymmetry prior to the surgery, or surgical complications.

EXPOSURE VARIABLE

The exposure variable was the timing, both preoperatively and 3 months postoperatively. This 3-month postoperative time point was chosen because complete healing of the bimaxillary surgery is expected by then, without any potential influence of condylar changes resulting from subsequent orthodontic treatment.

MAIN OUTCOME VARIABLES

The outcome variables are condylar position measurement, joint space (mm), and axial condylar angle (degrees).

COVARIATES

Demographics (age, sex) and surgical details (direction and amount of movement) were collected as covariates.

ANALYSES

Statistical analysis of condylar positional changes and correlations was performed using paired t-test and linear correlation (P value < .05), respectively.

RESULTS

The sample included 11 subjects (22 condyles), with a mean age of 24 ± 5.24 years. Both two-dimensional measurements and voxel-based three-dimensional superimposition showed significant changes in condylar position 3 months after bimaxillary surgery: inferior (0.45 ± 0.26 mm, P < .001), posterior (0.46 ± 0.39 mm, P = .003), lateral (0.38 ± 0.42 mm, P = .01) displacement, and inward rotation (5.21 ± 2.54°, P < .001). No significant correlation was found between jaw movement distance and condylar changes.

CONCLUSION AND RELEVANCE

To our knowledge, this is the first study to report measures of condylar changes at 3 months, when complete healing of the osteotomies would be expected, using Le Fort I osteotomy for maxillary advancement combined with bilateral sagittal split ramus osteotomy for mandibular setback. These changes are small in magnitude and may be of little relevance to patient care.

Evaluation of the mandibular condylar bone microarchitecture in people living with HIV

OBJECTIVES

People living with HIV (PLWH) have been shown to have lower bone density at the spine, hip, and radius. However, whether a similar bone phenotype is seen in craniofacial bones is not known. The goal of this study was to evaluate the bone microarchitecture of the mandibular condyle in PLWH.

METHODS

We recruited 212 participants, which included 88 HIV-negative participants and 124 PLWH on combination antiretroviral therapy with virological suppression from a single academic center. Each participant filled out a validated temporomandibular disorder (TMD) pain screening questionnaire and had cone beam computed tomography (CBCT) of their mandibular condyles. Qualitative radiographic evidence of temporomandibular joint disorders-osteoarthritis (TMJD-OA) assessment and quantitative microarchitecture analysis of their mandibular condylar bones were conducted.

RESULTS

There was no statistically significant difference in either self-reported TMD or in radiographic evidence of TMJD-OA in PLWH compared with HIV-negative controls. Linear regression analysis revealed that positive HIV status remained significantly associated with increased trabecular thickness, decreased cortical porosity, and increased cortical bone volume fraction after adjusting for race, diabetes, sex, and age.

CONCLUSION

PLWH have increased mandibular condylar trabecular bone thickness and cortical bone volume fraction compared with HIV-negative controls.

Semi or fully automatic tooth segmentation in CBCT images: a review

Cone beam computed tomography (CBCT) is widely employed in modern dentistry, and tooth segmentation constitutes an integral part of the digital workflow based on these imaging data. Previous methodologies rely heavily on manual segmentation and are time-consuming and labor-intensive in clinical practice. Recently, with advancements in computer vision technology, scholars have conducted in-depth research, proposing various fast and accurate tooth segmentation methods. In this review, we review 55 articles in this field and discuss the effectiveness, advantages, and disadvantages of each approach. In addition to simple classification and discussion, this review aims to reveal how tooth segmentation methods can be improved by the application and refinement of existing image segmentation algorithms to solve problems such as irregular morphology and fuzzy boundaries of teeth. It is assumed that with the optimization of these methods, manual operation will be reduced, and greater accuracy and robustness in tooth segmentation will be achieved. Finally, we highlight the challenges that still exist in this field and provide prospects for future directions.

The use of CBCT in orthodontics with special focus on upper airway analysis in patients with sleep-disordered breathing

Applications of cone-beam CT (CBCT) in orthodontics have been increasingly discussed and evaluated in science and practice over the last two decades. The present work provides a comprehensive summary of current consolidated practice guidelines, cutting-edge innovative applications, and future outlooks about potential use of CBCT in orthodontics with a special focus on upper airway analysis in patients with sleep-disordered breathing. The present scoping review reveals that clinical applications of CBCT in orthodontics are broadly supported by evidence for the diagnosis of dental anomalies, temporomandibular joint disorders, and craniofacial malformations. On the other hand, CBCT imaging for upper airway analysis-including soft tissue diagnosis and airway morphology-needs further validation in order to provide better understanding regarding which diagnostic questions it can be expected to answer. Internationally recognized guidelines for CBCT use in orthodontics are existent, and similar ones should be developed to provide clear indications about the appropriate use of CBCT for upper airway assessment, including a list of specific clinical questions justifying its prescription.

Temporomandibular involvement in children and adolescents with juvenile idiopathic arthritis: a 2-year prospective cohort study

This study aimed to clinically evaluate temporomandibular joint (TMJ) involvement in juvenile idiopathic arthritis (JIA) and the ability to identify and/or predict development of TMJ-deformities over time using cone beam computed tomography (CBCT). The predictive value of self-reported TMJ pain was also assessed. A prospective longitudinal cohort study comprising 54 children with JIA, 39 girls and 15 boys, was performed. All children had active disease at baseline, 50% with the subtype oligoarthritis. Repeated clinical orofacial and CBCT examinations were performed over a two-year period. At baseline, 39% had radiographic TMJ deformities (24% unilateral, 15% bilateral), at 2-year follow-up, 42% (p > 0.05). Both progressing and improving TMJ deformities were observed. An association was found between TMJ-deformities and self-reported TMJ pain at baseline (p = 0.01). Maximum unassisted mouth opening (MUO) was smaller for children with TMJ-deformities (p < 0.05). The prevalence of palpatory muscle pain was high (48-59%) but not predictive of development of TMJ-deformities. TMJ noises increased over time and crepitations were associated with TMJ-deformities (p < 0.05). In conclusion, in children with JIA, self-reported TMJ pain and dysfunction were common and predictive of TMJ deformities. TMJ deformities were associated with smaller MUO and palpatory TMJ pain as well as crepitations. Trial registration. ClinicalTrials.gov Protocol id: 2010/2089-31/2.

Noise-Optimized CBCT Imaging of Temporomandibular Joints-The Impact of AI on Image Quality

Background: Temporomandibular joint disorder (TMD) is a common medical condition. Cone beam computed tomography (CBCT) is effective in assessing TMD-related bone changes, but image noise may impair diagnosis. Emerging deep learning reconstruction algorithms (DLRs) could minimize noise and improve CBCT image clarity. This study compares standard and deep learning-enhanced CBCT images for image quality in detecting osteoarthritis-related degeneration in TMJs (temporomandibular joints). This study analyzed CBCT images of patients with suspected temporomandibular joint degenerative joint disease (TMJ DJD). Methods: The DLM reconstructions were performed with ClariCT.AI software. Image quality was evaluated objectively via CNR in target areas and subjectively by two experts using a five-point scale. Both readers also assessed TMJ DJD lesions. The study involved 50 patients with a mean age of 28.29 years. Results: Objective analysis revealed a significantly better image quality in DLM reconstructions (CNR levels; p < 0.001). Subjective assessment showed high inter-reader agreement (κ = 0.805) but no significant difference in image quality between the reconstruction types (p = 0.055). Lesion counts were not significantly correlated with the reconstruction type (p > 0.05). Conclusions: The analyzed DLM reconstruction notably enhanced the objective image quality in TMJ CBCT images but did not significantly alter the subjective quality or DJD lesion diagnosis. However, the readers favored DLM images, indicating the potential for better TMD diagnosis with CBCT, meriting more study.

Dental-dedicated MRI, a novel approach for dentomaxillofacial diagnostic imaging: technical specifications and feasibility

MRI is a noninvasive, ionizing radiation-free imaging modality that has become an indispensable medical diagnostic method. The literature suggests MRI as a potential diagnostic modality in dentomaxillofacial radiology. However, current MRI equipment is designed for medical imaging (eg, brain and body imaging), with general-purpose use in radiology. Hence, it appears expensive for dentists to purchase and maintain, besides being complex to operate. In recent years, MRI has entered some areas of dentistry and has reached a point in which it can be provided following a tailored approach. This technical report introduces a dental-dedicated MRI (ddMRI) system, describing how MRI can be adapted to fit dentomaxillofacial radiology through the appropriate choice of field strength, dental radiofrequency surface coil, and pulse sequences. Also, this technical report illustrates the possible application and feasibility of the suggested ddMRI system in some relevant diagnostic tasks in dentistry. Based on the presented cases, it is fair to consider the suggested ddMRI system as a feasible approach to introducing MRI to dentists and dentomaxillofacial radiology specialists. Further studies are needed to clarify the diagnostic accuracy of ddMRI considering the various diagnostic tasks relevant to the practice of dentistry.

The relationship between the oblique sagittal temporomandibular joint disc position and the volume surface area of the condyle in young TMD adults

The present study aims to compare the volume surface area of the condyle, the horizontal condylar axial angle and the disc-condyle angle between temporomandibular disorder (TMD) and asymptomatic volunteers, explore and analyze the relationship between the temporomandibular joint (TMJ) disc position in oblique sagittal plane and the volume surface area of the condyle in young adults with TMD symptoms. 84 young adult volunteers were received TMJ examination by Magnetic Resonance Imaging (MRI) and Cone Beam Computed Tomography (CBCT). TMD and asymptomatic volunteers were 42 each. MRI was used to assess the position of TMJ disc in the oblique sagittal plane with the condyle apex method. CBCT data were used for three-dimensional (3D) reconstruction of condyle and the measurements of the horizontal condylar axial angle and the volume surface area of the condyle. The condylar volume surface area of the TMD group was smaller than that of the asymptomatic group (p < 0.05), the disc condyle angle was larger than that of the asymptomatic group (p < 0.05), and no significant difference was found in the horizontal condylar axial angle (p > 0.05). In terms of correlation, the volume surface area of the condyle were negatively correlated with the position of the articular disc in TMD patients (p < 0.05). This significant negative correlation suggests that the possibility of disc displacement can be considered when poor condylar morphology is found.

Bibliometric analysis: Root and root canal morphology using cone-beam computed tomography

OBJECTIVES

This bibliometric analysis aimed to evaluate the leading nations, authors, journals, institutes, highly cited publications, and most commonly used keywords concerning scientific publications based on root and root canal morphology using the CBCT.

MATERIAL AND METHODS

For this bibliometric analysis, an extensive search was carried out on September 25, 2023 using the Scopus database. Pertinent articles in the field were scrutinized after applying inclusion and exclusion criteria. Data were evaluated using Vosviewer and Microsoft Excel.

RESULTS

A literature search revealed the initiation of scientific publication in 2008. Significant contributions made by Saudi Arabia, India, and China concerning the number of publications were seen. Similarly, Jazan University from SA was recognized as the leading institute. The Journal of Endodontics was the leading journal, while authors JNR Martins and G Gambarini produced the highest number of papers.

CONCLUSIONS

This bibliometric analysis demonstrated that scientific publications have increased tremendously since 2008. Significant contributions have been made by developing and developed nations. The Journal of Endodontics and Jazan University have been identified as the leading journal and institute.

The Role of Cone-Beam Computed Tomography CT Extremity Arthrography in the Preoperative Assessment of Osteoarthritis

Osteoarthritis (OA) is a prevalent disease and the leading cause of pain, disability, and quality of life deterioration. Our study sought to evaluate the image quality and dose of cone-beam computed tomography arthrography (CBCT-A) and compare them to digital radiography (DR) for OA diagnoses. Overall, 32 cases of CBCT-A and DR with OA met the inclusion criteria and were prospectively analyzed. The Kellgren and Lawrence classification (KLC) stage, sclerosis, osteophytes, erosions, and mean joint width (MJW) were compared between CBCT-A and DR. Image quality was excellent in all CBCT-A cases, with excellent inter-observer agreement. OA under-classification was noticed with DR for MJW (p = 0.02), osteophyte detection (<0.0001), and KLC (p < 0.0001). The Hounsfield Unit (HU) values obtained for the cone-beam computed tomography CBCT did not correspond to the values for multi-detector computed tomography (MDCT), with a greater mean deviation obtained with the MDCT HU for Modeled Based Iterative Reconstruction 1st (MBIR1) than for the 2nd generation (MBIR2). CBCT-A has been found to be more reliable for OA diagnosis than DR as revealed by our results using a three-point rating scale for the qualitative image analysis, with higher quality and an acceptable dose. Moreover, the use of this imaging technique permits the preoperative assessment of extremities in an OA diagnosis, with the upright position and bone microarchitecture analysis being two other advantages of CBCT-A.

Comparison of symptoms, signs and magnetic resonance imaging in children aged 5-18 years with temporomandibular joint disease

BACKGROUND

Temporomandibular joint diseases (TMD) are an important clinical condition in childhood as in adults. There is variation in the frequency and distribution of complaints in children about this disorder.

MATERIALS AND METHODS

This study was conducted on 407 children aged 5-18 years. Patients with dentofacial function problems, trauma, history of surgery, and malignancy were excluded from the study. Patients with temporomandibular magnetic resonance imaging in their records were classified as normal, reduction disc displacement and non-reduction disc displacement.

RESULTS

Patients symptoms were click (77.2%), pain (71.5%), headache (61.2%), bruxism (31.9%), locking (28%), difficulty in mouth opening (24.3%). The most common clinical findings are normal mouth opening (62.2%) and deviation (44.9%). When the MR results were examined, 55.1% of female and 66.6% of male were observed to be normal, and this statistically shows that males have more normal MR findings.

CONCLUSION

TMD are also observed in children. Clinical history and findings are helpful in diagnosis, but the contribution of imaging methods may be limited. If head and neck pain is detected in children, TMD should be kept in mind.

Imaging signs of temporomandibular joint osteoarthritis in an urban population of 65-year-olds: A cone beam computed tomography study

BACKGROUND

Symptoms of osteoarthritis (OA) in the temporomandibular joint (TMJ) may vary and possible causes should be further explored, such as prevalence and characteristics of imaging features.

OBJECTIVES

Investigate prevalence, gender differences and characteristics of imaging signs of TMJ-OA by cone beam computed tomography (CBCT) in a population-based sample of 65-year-old Oslo citizens.

MATERIALS AND METHODS

159 (86 women, 73 men) individuals randomly recruited from a cohort of 460 Oslo citizens were examined with CBCT. The TMJs were categorised as with imaging signs of OA, no OA or indeterminate for OA.

RESULTS

CBCT signs of TMJ-OA were found in 35% of the 159 participants: 47% of the women and 22% of the men. CBCT signs of TMJ-OA were unilateral in two-thirds of the TMJs and characterised by articular surface flattening and condylar osteophytes. In almost all joints with bone erosive findings, bone productive findings were also found. Participants with and without CBCT signs of TMJ-OA showed no significant difference in TMD pain screener. Fourteen of the 159 participants (9%) had pain-related TMD and 12 (8%) had been in contact with health care services due to TMD.

CONCLUSIONS

CBCT signs of TMJ-OA was common in this study group of 65-year-old Oslo citizens, found in every second woman and every fifth man. Articular surface flattening and bone productive changes, in particular condylar osteophytes, were the most frequent imaging features. Despite the high frequency of CBCT signs of TMJ-OA, few of the participants had pain-related TMD.

Temporomandibular joint disorders in seronegative spondyloarthritis: what a rheumatologist needs to know?

Temporomandibular joint (TMJ) can be affected in the context of spondyloarthritis (SpA) with detrimental impact on individuals' quality of life. Intra-articular inflammation, synovitis, enthesitis, disc displacement and cervical vertebrae malalignment are some of the pathophysiological phenomena involved. Temporomandibular joint disorders (TMD) incidence appears to be higher in patients with ankylosing spondylitis and psoriatic arthritis, especially when clinical evaluation includes not only imaging but relevant history, TMJ examination and diagnostic criteria for TMD. The Visual Analogue Scale (VAS) pain score and Health Assessment Questionnaire Disability Index (HAQ) quality of life score could be useful tools. Panoramic radiographs and ultrasound can be used for screening but in symptomatic patients magnetic resonance imaging (MRI) is preferable. Conservative management and early pharmacological treatment can prevent permanent joint impairment. For refractory cases, early referral to Legislation for Oral and Maxillofacial Surgery (OMFS) specialists is indicated. The aim of this narrative review is to address the involvement of TMJ in SpA and to encourage clinicians to incorporate TMJ assessment in their physical examination and basic screening.

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.

Effect of Molar Distalization on Condyle-Glenoid Fossa Relationship

Objective

It is essential to be aware of the potential effects of orthodontic treatment on tissues and anatomical structures associated with the masticatory system, especially the temporomandibular joint (TMJ). Little information is available about the consequences of molar distalization on the TMJ. Therefore, this study is aimed at investigating the changes of the condyle-fossa relationship after molar distalization using the distal jet appliance.

Materials and Methods

The sample consisted of twenty-five patients (mean age 20.4 ± 2.6) who underwent molar distalization by the distal jet appliance. CBCT scans were taken before (T0) and after (T1) the completion of the molar distalization. Joint spaces (anterior, superior, and posterior) and cephalometric vertical angles (SN.GOME and Björk sum) were measured and compared at T0 and T1.

Results

Superior and posterior joint spaces increased significantly after molar distalization (PS 0.29 mm, P < 0.001, SS 0.06 mm, P < 0.5). Vertical cephalometric angles also increased after molar distalization by the distal jet appliance (SN.GOME 0.92°, Björk 1.11°).

Conclusion

There was a statistically significant increase in the superior and posterior joint spaces after molar distalization. However, this increase may not be of clinical importance. The vertical dimension has also increased.

Investigation of Morphologic Changes in Temporomandibular Joint With Anterior Disk Displacement Based on 3-Dimensional Reconstructive Imaging

The objective of this study was to measure the association between the disk position and condylar alteration in patients diagnosed with anterior disk displacement (ADD) of temporomandibular joint (TMJ). A retrospective cross-sectional study was designed, dividing into 4 groups: normal articular disk position (NADP) of unilateral ADD patients (n=10), ADD with reduction (ADDwR, n=16), ADD without reduction (ADDwoR, n=24), and healthy volunteers (HV, n=30) based on magnetic resonance imaging and cone-beam computed tomography. After morphologic parameters were calculated from 3-dimensional reconstructive images, differences in parameters with respect to ADD status were tested with analysis of variance and Fisher least significant difference multiple comparisons were performed. Condylar volume of ADDwR, ADDwoR, NADP, and HVs were 1768.29±404.19, 1467.13±438.20, 1814.48±753.60, and 1914.66±476.48 mm, respectively, showing a significant downward trend from healthy disk to a displaced one ( P <0.05). Same trend also found in condylar superficial area, with the condylar superficial area of the ADDwR, ADDwoR, NADP, and HVs were 842.56±138.78 mm, 748.52±157.42 mm, 842.87±263.00 mm, and 892.73±164.19 mm, respectively. From NADP to ADDwR to ADDwoR, superior joint space (SJS) was declined, [SJS (NADP) (2.10±0.91 mm) > SJS (ADDwR) (1.85±0.61 mm) > SJS (ADDwoR) (1.50±0.50 mm), P =0.034]; medial joint space was significantly associated with the different disk displacement types ( P(HV-ADDwR) =0.001; P(HV-ADDwoR) =0.021; P(NADP-ADDwR) =0.022; P(ADDwR-ADDwoR) =0.001). Our findings suggest that condylar volume and superficial area, and superior and medial joint space, albeit with a small sample size, are significantly associated with different disk displacement types, detection of which might therefore be worth exploring for assessing ADD.

Comparative Evaluation of the Horizontal Condylar Guidance Using Protrusive Interocclusal Records, OPG, and CBCT in Edentulous Patients: An In Vivo Study

AIMS

A clinical study to compare the horizontal condylar guidance using protrusive interocclusal records, orthopantomography (OPG), and cone-beam computed tomography (CBCT) in edentulous patients.

SUBJECTS AND METHODS

Thirty-six edentulous subjects were selected as per predetermined criteria. Horizontal condylar guidance was recorded using protrusive interocclusal records (PIR), OPG, and CBCT for each patient. The PIR were obtained using extraoral Gothic arch tracers to program the Hanau articulator. The horizontal condylar guidance angles (HCGAs) were digitally constructed using appropriate software along the posterior slope of articular eminence for all radiographs. The collected data were recorded, tabulated, and statistically analyzed.

RESULTS

The condylar guidance angle values were tested for significance to compare the different angles. The correlation of HCGA measurements on both sides between the three groups was analyzed. The PIR and OPG methods (p = 0.001), as well as the OPG and CBCT methods (p = 0.001), show substantial differences on both sides. On the contrary, the PIR and CBCT methods did not differ significantly (p = 0.11).

CONCLUSION

Cone-beam computed tomography is as reliable and accurate as the clinical method. A significant correlation exists between the clinical method and CBCT. It can be used as a dependable adjunct to the clinical method of HCGA measurement.

CLINICAL SIGNIFICANCE

Cone-beam computed tomography can overcome the shortcomings of the conventional clinical methods to determine the accurate horizontal condylar guidance angulation measurement. It is safer with minimum discomfort and wastage of time for the patients.

Cone-beam computed tomographic characteristics in degenerative temporomandibular joint disease patients with chewing side preference

OBJECTIVES

This study is aimed at assessing the Cone-beam computed tomographic (CBCT) characteristics of temporomandibular joints (TMJ) in degenerative temporomandibular joint disease (DJD) patients with chewing side preference (CSP).

MATERIALS AND METHODS

CBCT images of 98 patients with DJD (67 with CSP and 31 without CSP) and 22 asymptomatic participants without DJD were measured retrospectively to compare the osteoarthritic changes and the morphology of TMJ. Quantitative analysis of the TMJ radiographic images was performed to present a comparison between the three inter-group groups and between the two sides of the joints.

RESULTS

The frequencies of the articular flattening and surface erosion occur more often in the preferred side joints of DJD patients with CSP than the contralateral side. In addition, the horizontal angle of condyle, the depth of glenoid fossa (DGF), and the inclination of articular eminence (IAE) were larger in DJD patients with CSP than that in asymptomatic participants (p<0.05). Also, the condylar anteroposterior dimension of preferred side joints was significantly less than that of non-preferred side (p=0.026), while the width of condyles (p=0.041) and IAE (p=0.045) was greater.

CONCLUSIONS

DJD patients with CSP appear to have a higher prevalence of osteoarthritic changes, with the morphological changes such as flat condyle, deep glenoid fossa, and steep articular eminence, which might be considered the characteristic imaging features.

CLINICAL RELEVANCE

This study found that CSP is a predisposing factor for the development of DJD, and attention should be paid to the existence of CSP in DJD patients during the clinical practice.

Mechanism and potential contributing factors to temporomandibular joint osteoarthritis

OBJECTIVE

To investigate the mechanism of and potential contributing factors to temporomandibular joint osteoarthritis (TMJOA) caused by oestrogen deficiency with a persistent high bite force.

MATERIALS AND METHODS

A TMJOA model was generated by subjecting 6-week-old female rats to ovariectomy (OVX) and feeding them a hard feed. The rats (n = 12/group) were divided into sham (control); OVX; OVX+hard feed (HF); OVX+hard feed+local-joint injection of 17β-oestradiol (an oestrogen) (E2); and OVX+hard feed+local-joint injection of rapamycin (an autophagy activator) (RAPA)groups. Condyles were stained with haematoxylin-eosin and Safranin O Fast Green. The expression of Beclin 1, LC3 and p-mTOR in condylar cartilages was analysed.

RESULTS

Tissue staining revealed thinner condylar cartilage, varying numbers or fewer hypertrophic chondrocytes, and lower proteoglycan content in the cartilage matrix of the OVX group. These characteristics were more pronounced in the HF group, but were significantly recovered in the E2 and RAPA groups. Immunohistochemical staining revealed significantly lower autophagic flux in OVX/HF groups and a higher one in E2/RAPA groups.

CONCLUSIONS

A persistent high bite force could aggravate TMJOA induced by oestrogen deficiency, and the application of oestrogen or rapamycin could delay its progression. Additionally, autophagy may play a role in the development of TMJOA.

Effects of osseous structure based on three-dimensional reconstructive imaging evaluation in the assessment of temporomandibular joint disc position

OBJECTIVES

This pilot morphological study aimed to investigate the association between anterior disc displacement (ADD) and the status of the mandibular condyle and articular fossa.

MATERIALS AND METHODS

Thirty-four patients were divided into a normal articular disc position group and an ADD with and without reduction group. Images reconstructed were used to determine multiple group comparisons of these three different types of disc position, and the diagnostic efficacy for the morphological parameters with significant group difference was analyzed to assess.

RESULTS

The condylar volume (CV), condylar superficial area (CSA), superior joint space (SJS), and medial joint space (MJS) all exhibited obvious changes (P < 0.05). Additionally, they all had a reliable diagnostic accuracy in differentiating between normal disc position and ADD with an AUC value from 0.723 to 0.858. Among them, the CV, SJS, and MJS (P < 0.05) had a significantly positive impact on the groups by analysis of multivariate logistic ordinal regression model.

CONCLUSIONS

The CV, CSA, SJS, and MJS are significantly associated with different disc displacement types. The condyle in ADD exhibited altered dimensions. These could be promising biometric markers for assessing ADD.

CLINICAL RELEVANCE

The morphological changes of mandibular condyle and glenoid fossa were significantly influenced by the status of disc displacement, and condyles with disc displacement had three-dimensionally altered condylar dimensions, irrespective of age and sex.

A Comparative Preliminary Randomized Clinical Study to Evaluate Heavy Bupivacaine Dextrose Prolotherapy (HDP) and Autologous Blood Injection (ABI) for Symptomatic Temporomandibular Joint Hypermobility Disorder

Purpose

Temporomandibular joint (TMJ) sub-luxation can have a significant psycho-social impact on a patients' well-being. Several treatment modalities have been described in the literature for the same. The present study was undertaken to investigate the efficacy of heavy bupivacaine-dextrose prolotherapy (HDP) for the peri-articular tissues, superior joint space and the retro-discal area in the patients with symptomatic chronic sub-luxation.

Materials and Methods

A preliminary clinical study was conducted among 60 patients diagnosed with chronic painful sub-luxation of the TMJ. Patients were divided into control group (CG), n = 30, where autologous blood was injected in the superior joint space, peri-capsular tissues and retro-discal area bilaterally as per the predetermined protocol; and the study group (SG), n = 30 patients were administered heavy bupivacaine-dextrose injection bilaterally in the peri-articular tissues, superior joint space and retro-discal area. The efficacy of the treatment was evaluated by assessing pain, maximum inter-incisal opening (MIO), changes in computed tomography scan, magnetic resonance imaging study, number and need for subsequent injections in both the groups.

Result

Among the 60 patients, majority of the patients exhibited successful outcome after both the interventions, ABI and HDP. There was statistically significant reduction in recorded pain score with reduced MIO post-treatment. No morphological changes were noted in the condyle in both the groups. No complications were recorded among the study population.

Conclusion

HDP is a safe and simple modality for treating symptomatic sub-luxation with predictable clinical outcome. Heavy bupivacaine-dextrose can be considered as a prolotherapeutic agent for symptomatic chronic temporomandibular joint sub-luxation with the pharmacological benefit of local anaesthesia and proliferent delivery through the same injection.

Classifying Temporomandibular Disorder with Artificial Intelligent Architecture Using Magnetic Resonance Imaging

This study proposes a new diagnostic tool for automatically extracting discriminative features and detecting temporomandibular joint disc displacement (TMJDD) accurately with artificial intelligence. We analyzed the structural magnetic resonance imaging (MRI) images of 52 patients with TMJDD and 32 healthy controls. The data were split into training and test sets, and only the training sets were used for model construction. U-net was trained with 100 sagittal MRI images of the TMJ to detect the joint cavity between the temporal bone and the mandibular condyle, which was used as the region of interest, and classify the images into binary categories using four convolutional neural networks: InceptionResNetV2, InceptionV3, DenseNet169, and VGG16. The best models were InceptionV3 and DenseNet169; the results of InceptionV3 for recall, precision, accuracy, and F1 score were 1, 0.81, 0.85, and 0.9, respectively, and the corresponding results of DenseNet169 were 0.92, 0.86, 0.85, and 0.89, respectively. Automated detection of TMJDD from sagittal MRI images is a promising technique that involves using deep learning neural networks. It can be used to support clinicians in diagnosing patients as having TMJDD.

Do TMJ MRI diagnosis support clinical examination diagnosis following DC/TMD criteria?

PURPOSE

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.

METHODS

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.

RESULTS

A total of fifty patients (100 TMJs) were enrolled with 38 females and 12 males. The mean ages were 31.92 and 31.75 years, 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.

CONCLUSION

The DC/TMD clinical examination performed well in all types of disc displacement but is less reliable in detecting the presence of degenerative disc diseases and subluxation.

Comprehensive positional and morphological assessments of the temporomandibular joint in adolescents with skeletal Class III malocclusion: a retrospective CBCT study

BACKGROUND

Condyle-fossa relationships in adolescents with skeletal Class III malocclusion remain unclear. Therefore, this study used cone-beam computed tomography (CBCT) to evaluate the position and morphology of the temporomandibular joint (TMJ) in adolescents with skeletal Class III malocclusion.

METHODS

In this cross-sectional retrospective study, CBCT images from 90 adolescents with skeletal Class III malocclusion and 30 controls were analysed. Adolescents with skeletal Class III malocclusion were divided into different groups based on (1) sex (male and female), (2) sides (right and left), (3) age (early, middle, and late adolescence), and (4) vertical skeletal patterns (hyperdivergent, normodivergent, and hypodivergent). Morphology of the condyle and fossa as well as condylar position, was compared among groups. Data were collected and submitted for statistical analysis. This study adheres to STROBE guidelines.

RESULTS

Regarding the intergroup comparisons, there were significant differences in TMJ position and morphology between the skeletal Class III malocclusion with different vertical skeletal patterns and control groups (P < 0.05). Within groups, condyle-fossa relationships differed significantly according to sex, age, and vertical skeletal patterns (P < 0.05); however, the mean values were not statistically different between left and right sides in adolescents with skeletal Class III malocclusion.

CONCLUSIONS

Our findings can be used clinically and radiographically to evaluate the condyle and glenoid fossa features in adolescents with skeletal Class III malocclusion, providing a basis for better TMD diagnosis and orthodontic treatment.

Temporomandibular joint involvement in individuals with ankylosing spondylitis: A scoping review

OBJECTIVE

This scoping review aimed to identify the signs and symptoms of temporomandibular joint (TMJ) involvement in individuals with ankylosing spondylitis (AS).

DESIGN

Systematic literature searches were performed on PubMed, Embase, and Web of Science databases (up to April 2022). Studies with signs and symptoms of temporomandibular joint disorder (TMD) in adults with AS were included. TMJ outcomes were extracted and analyzed qualitatively.

RESULTS

From 527 potentially eligible studies, 22 were included. A total of 4309 individuals with AS were evaluated, aged between 18 and 80 years, being males approximately 65% of the sample. Signs and symptoms of pain, tenderness to palpation on TMJ and masticatory muscles, joint noises (i.e., clicking or crepitus), limited mouth opening, disc displacement, and radiographic changes were often observed.

CONCLUSION

The available evidence shows that different signs and symptoms of TMD co-occur with AS disease, with a higher prevalence of TMD observed in individuals with AS than in individuals without AS. Indeed, it seems that individuals suffering from AS disease have an increased risk of developing TMD.

Evaluation of treatment with unilateral mandibular sagittal split ramus osteotomy and maxillary osteotomy in patients with condylar osteochondroma and mandibular asymmetry: A retrospective case series

The aim of the study was to describe an approach where condylar resection with condylar neck preservation was combined with Le Fort I osteotomy and unilateral mandibular sagittal split ramus osteotomy (SSRO). Patients with a unilateral condylar osteochondroma combined with dentofacial deformity and facial asymmetry who underwent surgery between January 2020 and December 2020 were enrolled. The operation included condylar resection, Le Fort I osteotomy and contralateral mandibular sagittal split ramus osteotomy (SSRO). Simplant Pro 11.04 software was used to reconstruct and measure the preoperative and postoperative craniomaxillofacial CT images. The deviation and rotation of the mandible, change in the occlusal plane, position of the "new condyle" and facial symmetry were compared and evaluated during follow-up. Three patients were included in the present study. The patients were followed up for 9.6 months on average (range, 8-12). Immediate postoperative CT images showed that the mandible deviation and rotation and occlusion plane canting decreased significantly postoperatively; facial symmetry was improved but still compromised. During the follow-up, the mandible gradually rotated to the affected side, the position of the "new condyle" moved further inside toward the fossa, and both the mandible rotation and facial symmetry were more significantly improved. Within the limitations of the study it seems that for some patients a combination of condylectomy with condylar neck preservation and unilateral mandibular SSRO can be effective in achieving facial symmetry.

Machine-learning-based detection of degenerative temporomandibular joint diseases using lateral cephalograms

INTRODUCTION

Degenerative temporomandibular joint diseases (DJDs) are common diseases in dental practice, characterized by a series of degenerative processes in the temporomandibular joint. Early clinical detection of DJD by dental practitioners can be beneficial to prevent or alleviate the further progression of the disease. This study aimed to develop a cephalogram-based multidimensional nomogram to screen DJD.

METHODS

A total of 502 patients (170 normal and 332 with DJD) were randomly assigned to a training set (n = 351) or a validation set (n = 151). Thirty-six cephalometric parameters were extracted from the cephalograms to be used as input for a predictive machine-learning algorithm. Multivariable logistic regression was used to construct a combined model for visualization in the form of a nomogram. Receiver operating characteristic curve, calibration testing, and decision curve analyses were conducted to evaluate the performance of the combined model.

RESULTS

A Ceph score consisting of 22 cephalometric parameters were significantly associated with DJD (P <0.01). A combined model that consisted of Ceph scores and clinical features (including age, gender, limited mouth opening, crepitus, etc.) performed well in the receiver operating characteristic curve (area under the curve, 0.893), calibration test, and decision curve analyses, indicating its potential clinical value.

CONCLUSIONS

This study constructed and verified a multidimensional nomogram consisting of Ceph scores and clinical features, which may contribute to the clinical screening of DJD in dental practice. Future studies are needed to test the reliability of the model with similar parameters.

Temporomandibular Joint Osteoarthritis Diagnosis Employing Artificial Intelligence: Systematic Review and Meta-Analysis

The aim was to systematically synthesize the current research and influence of artificial intelligence (AI) models on temporomandibular joint (TMJ) osteoarthritis (OA) diagnosis using cone-beam computed tomography (CBCT) or panoramic radiography. Seven databases (PubMed, Embase, Scopus, Web of Science, LILACS, ProQuest, and SpringerLink) were searched for TMJ OA and AI articles. We used QUADAS-2 to assess the risk of bias, while with MI-CLAIM we checked the minimum information about clinical artificial intelligence modeling. Two hundred and three records were identified, out of which seven were included, amounting to 10,077 TMJ images. Three studies focused on the diagnosis of TMJ OA using panoramic radiography with various transfer learning models (ResNet model) on which the meta-analysis was performed. The pooled sensitivity was 0.76 (95% CI 0.35-0.95) and the specificity was 0.79 (95% CI 0.75-0.83). The other studies investigated the 3D shape of the condyle and disease classification observed on CBCT images, as well as the numerous radiomics features that can be combined with clinical and proteomic data to investigate the most effective models and promising features for the diagnosis of TMJ OA. The accuracy of the methods was nearly equivalent; it was higher when the indeterminate diagnosis was excluded or when fine-tuning was used.

Myogenous Temporomandibular Disorders: Diagnostic Concepts and Prospective Pilot Study on Extracorporeal Shockwave Therapy

The aims of this article are to discuss the current, and potential future directions, in the diagnosis of myogenous temporomandibular disorders (M-TMD), as well as to report a pilot study to investigate the feasibility and clinical outcomes of extracorporeal shockwave therapy (ESWT) in the treatment of M-TMD. Forty-one adult patients presented with M-TMD were recruited into the study and randomized into two groups: Group 1 received ESWT treatment, whereas Group 2 received placebo treatment. The variables investigated were pain, measured by a numerical rating scale (NRS) and mouth opening. Twenty-six patients (Group 1: n = 14, mean age = 45.3 (16.7) years; Group 2: n = 12, mean age = 46.8 (19.7) years) completed 1-year follow up and were included into the final analysis. In both groups, reduction in pain and increase in MO (unassisted maximum, assisted maximum, and pain-free) were seen at post-treatment 1 year. There were more reduction in pain and increase in all MO in Group 1 than Group 2, but statistical significance was not detected. No major complications were encountered in this study. Although significant differences were not seen between groups, this prospective pilot study provided preliminary evidence that ESWT is safe and potentially beneficial in the treatment of M-TMD.

Temporomandibular Joint Osteoarthritis: Pathogenic Mechanisms Involving the Cartilage and Subchondral Bone, and Potential Therapeutic Strategies for Joint Regeneration

The temporomandibular joint (TMJ) is a specialized synovial joint that is crucial for the movement and function of the jaw. TMJ osteoarthritis (TMJ OA) is the result of disc dislocation, trauma, functional overburden, and developmental anomalies. TMJ OA affects all joint structures, including the articular cartilage, synovium, subchondral bone, capsule, ligaments, periarticular muscles, and sensory nerves that innervate the tissues. The present review aimed to illustrate the main pathomechanisms involving cartilage and bone changes in TMJ OA and some therapeutic options that have shown potential restorative properties regarding these joint structures in vivo. Chondrocyte loss, extracellular matrix (ECM) degradation, and subchondral bone remodeling are important factors in TMJ OA. The subchondral bone actively participates in TMJ OA through an abnormal bone remodeling initially characterized by a loss of bone mass, followed by reparative mechanisms that lead to stiffness and thickening of the condylar osteochondral interface. In recent years, such therapies as intraarticular platelet-rich plasma (PRP), hyaluronic acid (HA), and mesenchymal stem cell-based treatment (MSCs) have shown promising results with respect to the regeneration of joint structures or the protection against further damage in TMJ OA. Nevertheless, PRP and MSCs are more frequently associated with cartilage and/or bone repair than HA. According to recent findings, the latter could enhance the restorative potential of other therapies (PRP, MSCs) when used in combination, rather than repair TMJ structures by itself. TMJ OA is a complex disease in which degenerative changes in the cartilage and bone develop through intricate mechanisms. The regenerative potential of such therapies as PRP, MSCs, and HA regarding the cartilage and subchondral bone (alone or in various combinations) in TMJ OA remains a matter of further research, with studies sometimes obtaining discrepant results.

Occlusal Splint Therapy Combined with Cranio-Temporomandibular Kinesiotherapy in Patients with Temporomandibular Disorders-A CBCT Study

Occlusal splints are used as a non-invasive treatment for patients diagnosed with temporomandibular disorders (TMD). Another non-invasive treatment option for TMD patients is kinesiotherapy, which may be used alone or in conjunction with occlusal splint therapy. The aim of this study was to evaluate the changes in the intra-articular spaces of the temporomandibular joint (TMJ) after occlusal splint therapy combined with cranio-temporomandibular kinesiotherapy in TMD patients. Twenty-four patients (N = 24) diagnosed with TMD according to Research Diagnostic Criteria for Temporomandibular Disorders (RDC/TMD) were included. Cone beam computed tomography (CBCT) images were taken before and after treatment. The anterior, superior, posterior, and medial joint spaces were measured on the CBCT images, and the condylar ratio was calculated using Pullinger and Hollender's formula. Additionally, the thickness of the glenoid fossa (GFT), condylar medio-lateral widths (MLW), and condylar height (HCo) were measured. The condylar ratio was significantly higher after treatment (p = 0.049). The changes in dimensions of the anterior, superior, posterior and medial joint spaces were not statistically significant after treatment. No statistically significant differences were found in the dimensions of the GFT, MLW, and HCo post treatment. The condylar position did not shift anteriorly in a statistically significant way after occlusal splint therapy combined with cranio-temporomandibular kinesiotherapy in TMD patients.

Association between Psychological Status and Condylar Bony Changes in Adults: A Retrospective Survey-Based Study

Background: This article studies the association between psychological status and condylar bony changes in adults and assesses psychological questionnaires as an indicator of potential condylar bony changes. It is meaningful because condylar bony changes, a severe subtype of TMD and big concern in orthodontic treatment, would likely be ignored in patients with few TMD symptoms, in which case, even with potential psychological problems (depression, somatization and anxiety) being noticed, orthodontists may underestimate the possibility or severity of condylar bony changes and thus may not perform relevant examinations. Methods: A total of 195 adults (145 female and 50 male) who consulted orthodontists and had clinical records were included in this study. Initial CBCT images taken before orthodontic treatment were used for observing their condylar bony changes, and a comprehensive questionnaire conducted by each adult to evaluate psychological status was collected. Age, sex, TMD symptom history, scores on Patient Health Questionnaire-9 (PHQ-9), PHQ-15 and Generalized Anxiety Disorder-7 (GAD-7), and condylar bony changes of these adults were recorded. Odds ratios (OR) and 95% confidence intervals (CIs) for identifying the independent risk factors associated with condylar bony changes were calculated with univariate and multivariate logistic regression analysis. The kappa statistic was used to assess intraobserver reliability of CBCT analysis. Results: The scores of PHQ-15 (OR: 2.088, 95% CI: 1.061−4.108, p < 0.05) and GAD-7 (OR: 2.133, 95% CI: 1.082−4.204, p < 0.05) were correlated with the condylar bony changes on CBCT. Besides, the probability of having condylar bony changes was positively correlated with the number of psychological problems concomitantly present in an adult (OR: 1.440, 95% CI: 1.10−1.867, p < 0.01). The intraobserver agreement value for CBCT analysis was substantial (κ = 0.732). Conclusions: This study found that positive PHQ-15 (somatization) and GAD-7 (anxiety) scores were associated with condylar bony changes in adults. Moreover, the number of psychological problems concomitantly present in an adult was positively associated with the probability of having condylar bony changes.

Evaluation of Cortical Bone Formation on Mandibular Condyle in Asymptomatic Adolescents and Young Adults Using Cone-Beam Computed Tomography

The aim of this study was to evaluate cortical bone formation on the mandibular condyle using cone-beam computed tomography (CBCT) in asymptomatic adolescents and young adults and to evaluate the relationship between age and sex. CBCT images that can evaluate the shape of the mandibular condyle were selected from asymptomatic patients aged 13−25. The degree of cortication on the mandibular condyle (CMC) was evaluated using CBCT images reconstructed in the axial, sagittal, and coronal planes. CBCT data of 829 patients (413 males, 416 females) were selected and then the left and right images of all patients were acquired; consequently, a total of 1658 temporomandibular joint-related images were evaluated in this study. The degree of CMC was correlated with age in men and women (p < 0.05). The frequency of CMC 0 disappeared in woman aged 20 years and in men aged 21 years. Cortical bone formation of the mandibular condyle was completed at age 22 years in women and 24 years in men. The degrees of cortical bone formation of the mandibular condyle between men and women showed significant differences between the ages of 15−19 and 22 years. This difference can be interpreted as a different mandible growth period between the sexes.

Viscosupplementation in the upper and lower compartments of the temporomandibular joint checked by ultrasonography in an ex vivo and in vivo study

Viscosupplementation (VS) of the temporomandibular joint (TMJ) aims to treat temporomandibular dysfunction (TMD) by stimulating synovial cells to improve intracapsular lubrication. The purpose of the present study was to assess a VS protocol planned with the aid of cone-beam computed tomography (CBCT) and checked by ultrasonography (US). The study was carried out in 3 stages. The first was to check the correspondence between the proposed facial reference points and the osseous components of the joint by means of CBCT. In the second stage, the upper and lower compartments of 20 TMJs of fresh frozen cadavers were injected with coloured liquids, and the accuracy of the technique was confirmed by dissecting the anatomical specimens. The third stage consisted of VS in 10 patients (20 TMJs), with real-time verification of the location of the needle tip by means of ultrasonography. CBCT confirmed the correct locations of the marked points used in the proposed VS protocol. The dissections showed that 13 of the 14 injections effectively reached the upper and lower compartments. The location of the needle tip was effectively verified by ultrasonography, confirming the correct access to both compartments. The proposed protocol was effective for accessing the upper and lower compartments of the TMJ. The evaluated protocol proved to be accurate, safe and clinically reproducible means of VS in the upper and lower compartments of the TMJ.

Comparison of symptoms, signs, gender, and magnetic resonance images of temporomandibular joint disorder patients

OBJECTIVE

To compare patients' complaints, clinician's examination findings, and magnetic resonance imaging (MRI) findings by considering gender.

METHODS

Temporomandibular joint (TMJ) pain, difficulty in mouth opening, masseter tenderness, deviation, clicking sound, bruxism, restriction, normal occlusion and normal mouth opening symptoms, and findings of temporomandibular disorder (TMD) patients who came to the author's outpatient clinic were recorded. These recordings were compared with MRI.

RESULTS

In the study, symptoms, signs, and MRIs of 276 TMD patients were analyzed, including gender. No difference was observed in terms of symptoms, signs, or MRI results for either gender. MRI findings were correlated with restriction and normal mouth opening in both groups (p < 0.05). Normal MRI findings were observed in 52.5% of the MRI results.

CONCLUSION

Except for normal mouth opening and limitation, MRI findings did not provide a significant result. Therefore, careful detection of symptoms and signs rather than MRI helps in diagnosis.

Evaluation of condyle-fossa relationships in skeletal Class I malocclusion with variable degrees of deep overbite and open bite

OBJECTIVE

To compare the temporomandibular joint (TMJ) position and shape between skeletal Class I subjects with different degrees of deep overbite or open bite and unaffected peers.

METHODS

Cone beam computed tomography (CBCT) images of 90 participants, equally divided into deep bite, open bite, and control groups (DBG, OBG, and CG, respectively), were analyzed. The DBG and OBG were further subdivided into three subgroups based on the severity. Linear and angular measurements were used to determine the positional and morphological characteristics of the TMJ.

RESULTS

DBG showed significantly larger superior joint space, anterior inclination of the condyle, and articular eminence inclination than CG and OBG. The severity of deep bite and open bite significantly influenced the TMJ position and morphology.

CONCLUSION

In severe deep overbite and open bite cases, there were considerable alterations in TMJ components, most likely as a result of functional demands.

Diagnosis of temporomandibular disorders using artificial intelligence technologies: A systematic review and meta-analysis

Background

Artificial intelligence (AI) algorithms have been applied to diagnose temporomandibular disorders (TMDs). However, studies have used different patient selection criteria, disease subtypes, input data, and outcome measures. Resultantly, the performance of the AI models varies.

Objective

This study aimed to systematically summarize the current literature on the application of AI technologies for diagnosis of different TMD subtypes, evaluate the quality of these studies, and assess the diagnostic accuracy of existing AI models.

Materials and methods

The study protocol was carried out based on the preferred reporting items for systematic review and meta-analysis protocols (PRISMA). The PubMed, Embase, and Web of Science databases were searched to find relevant articles from database inception to June 2022. Studies that used AI algorithms to diagnose at least one subtype of TMD and those that assessed the performance of AI algorithms were included. We excluded studies on orofacial pain that were not directly related to the TMD, such as studies on atypical facial pain and neuropathic pain, editorials, book chapters, and excerpts without detailed empirical data. The risk of bias was assessed using the QUADAS-2 tool. We used Grading of Recommendations, Assessment, Development, and Evaluations (GRADE) to provide certainty of evidence.

Results

A total of 17 articles for automated diagnosis of masticatory muscle disorders, TMJ osteoarthrosis, internal derangement, and disc perforation were included; they were retrospective studies, case-control studies, cohort studies, and a pilot study. Seven studies were subjected to a meta-analysis for diagnostic accuracy. According to the GRADE, the certainty of evidence was very low. The performance of the AI models had accuracy and specificity ranging from 84% to 99.9% and 73% to 100%, respectively. The pooled accuracy was 0.91 (95% CI 0.76–0.99), I² = 97% (95% CI 0.96–0.98), p < 0.001.

Conclusions

Various AI algorithms developed for diagnosing TMDs may provide additional clinical expertise to increase diagnostic accuracy. However, it should be noted that a high risk of bias was present in the included studies. Also, certainty of evidence was very low. Future research of higher quality is strongly recommended.

Analysis of the Volumetric Asymmetry of the Mandibular Condyles Using CBCT

Objectives

The aim of this study was to analyse volumetric asymmetries between the right and left condyles in relation to age, gender, and dental status.

Materials and methods

A retrospective analysis of 150 cone beam computed tomography (CBCT) scans was conducted. A single investigator performed the volumetric analysis of the CBCT scans using Vesalius 3D software. The volumetric data were analysed in relation to the gender, age, and dental status.

Results

The mean right condylar volume was significantly higher (P < .01) than the left condylar volume. Right and left condylar volumes were significantly higher (P < .01) in male study participants when compared to female study participants. There was no significant difference (P = .47) in the volumetric asymmetry between the male and female study participants. The volumetric asymmetry was significantly higher (P < .01) in the older age groups when compared to the younger age groups. The volumetric asymmetry was significantly higher (P < .01) in the partially and completely edentulous patients when compared to the dentate study participants. The condylar volume on the side having a partially edentulous area was significantly lower than the condylar volume of the contralateral dentate side (P < .001).

Conclusions

The volumetric asymmetry between the right and left condyle significantly increases with age and edentulousness. The result of the study encourages the clinicians to perform volumetric evaluation of the condyles in cases of radiographically evident condylar asymmetries to obtain a more accurate diagnosis.

Controversial Aspects of Diagnostics and Therapy of Arthritis of the Temporomandibular Joint in Rheumatoid and Juvenile Idiopathic Arthritis-An Analysis of Evidence- and Consensus-Based Recommendations Based on an Interdisciplinary Guideline Project

Introduction: Due to potentially severe sequelae (impaired growth, condylar resorption, and ankylosis) early diagnosis of chronic rheumatic arthritis of the temporomandibular joint (TMJ) and timely onset of therapy are essential. Aim: Owing to very limited evidence the aim of the study was to identify and discuss controversial topics in the guideline development to promote further focused research. Methods: Through a systematic literature search, 394 out of 3771 publications were included in a German interdisciplinary guideline draft. Two workgroups (1: oral and maxillofacial surgery, 2: interdisciplinary) voted on 77 recommendations/statements, in 2 independent anonymized and blinded consensus phases (Delphi process). Results: The voting results were relatively homogenous, except for a greater proportion of abstentions amongst the interdisciplinary group (p < 0.001). Eighty-four percent of recommendations/statements were approved in the first round, 89% with strong consensus. Fourteen recommendations/statements (18.2%) required a prolonged consensus phase and further discussion. Discussion: Contrast-enhanced MRI was confirmed as the method of choice for the diagnosis of TMJ arthritis. Intraarticular corticosteroid injection is to be limited to therapy-refractory cases and single injection only. In adults, alloplastic joint replacement is preferable to autologous replacement. In children/adolescents, autologous reconstruction may be performed lacking viable alternatives. Alloplastic options are currently still considered experimental.

Orthodontic retreatment of an adult woman with mandibular backward positioning and temporomandibular joint disorder: A case report

BACKGROUND

The role of occlusal factors on the occurrence of temporomandibular joint disorders (TMDs) is still unclear and it is tricky for orthodontists to treat malocclusions in patients with TMDs. We report the case of the second orthodontic treatment of an adult female with Class II division 2 malocclusion associated with TMD. With the removal of anterior occlusal interference, TMD symptoms were alleviated and cone beam computed tomography (CBCT) images showed the bilateral condyles shifted forward.

CASE SUMMARY

This case report presented an orthodontic retreatment of an adult female with TMD and mandibular backward positioning based on CBCT examination and Joint Space Index (JSI) analysis. The left and right JSI values of -38.5 and -52.6 indicated that the position of bilateral condyles had posterior displacement. Ten years prior to this evaluation, she underwent orthodontic treatment resulting in the extraction of two upper premolars and one lower central incisor. The joint symptoms, including pain and sounds, were alleviated along with verified mandibular forward repositioning by extraction of another lower central incisor.

CONCLUSION

Mandibular backward positioning could be associated with TMD. JSI analysis based on CBCT is a convenient way to examine condylar positions quantitatively.

Correlation of clinical manifestations and condylar morphology of patients with temporomandibular degenerative joint diseases

OBJECTIVE

To study the correlation between condylar morphology and clinical manifestations in patients with degenerative joint disease (DJD) of the temporomandibular joint (TMJ).

METHODS

A total of 175 joints of 131 patients with DJD were included. Data on patients' basic information and symptoms were collected and analyzed. Condylar morphology was evaluated using cone beam computed tomography (CBCT). The correlation between the condylar morphology and clinical manifestations was analyzed.

RESULTS

The prevalence of joint noises, clicks, and crepitus was 93/175 (53%), 73/175 (42%), and 20/175 (11%), respectively. Condylar anteroposterior diameter and condylar height were correlated with pain. There was a correlation between the shape of the condyle in the sagittal plane and joint noise.

CONCLUSION

Condylar morphology and clinical features of DJD were correlated to some extent.

Temporomandibular joint involvement in children with juvenile idiopathic arthritis-Symptoms, clinical signs and radiographic findings

BACKGROUND

Although many children with juvenile idiopathic arthritis (JIA) develop arthritis and deformity of the temporomandibular joint (TMJ), many go undetected.

OBJECTIVE

This study investigates whether findings from patient history and clinical examination using the Research Diagnostic Criteria for Temporomandibular Disorders (RDC/TMD) can be used to diagnose TMJ involvement.

METHODS

As a part of the screening program, 59 consecutive JIA patients age 7-14 years underwent a clinical examination according to RDC/TMD including self-reported orofacial pain and pain related to jaw function, and cone beam computer tomography (CBCT). Data were obtained from the patient's medical charts. Patients were divided into two groups based on the presence or absence of TMJ deformities on CBCT.

RESULTS

Self-reported TMJ symptoms before inclusion were reported by 52% of children with and 18% of children without TMJ deformities on CBCT (p = .020). On a group level, the maximum unassisted (mouth) opening (MUO) with and without pain was within the normal range, but children with TMJ deformities showed a significantly smaller MUO with pain (p = .035). A diagnosis of osteoarthritis and osteoarthrosis was more prevalent in children with TMJ deformities.

CONCLUSION

Although there were few differences between children with and without radiographic TMJ deformities, self-reported previous TMJ symptoms and reduced MUO with pain could indicate the presence of TMJ involvement. However, radiographic examinations are needed to confirm TMJ involvement. Thus, this study indicates that the RDC/TMD protocol is a blunt tool when targeting TMJ involvement in JIA.

Molecular signaling in temporomandibular joint osteoarthritis

Objective

Temporomandibular joint (TMJ) osteoarthritis (OA) is a type of TMJ disorders with clinical symptoms of pain, movement limitation, cartilage degeneration and joint dysfunction. This review article is aiming to summarize recent findings on signaling pathways involved in TMJ OA development and progression.

Methods

Most recent findings in TMJ OA studies have been reviewed and cited.

Results

TMJ OA is caused by inflammation, abnormal mechanical loading and genetic abnormalities. The molecular mechanisms related to TMJ OA have been determined using different genetic mouse models. Recent studies demonstrated that several signaling pathways are involved in TMJ OA pathology, including Wnt/β-catenin, TGF-β and BMP, Indian Hedgehog, FGF, NF-κB, and Notch pathways, which are summarized in this review article. Alterations of these signaling pathways lead to the pathological changes in TMJ tissues, affecting cartilage matrix degradation, catabolic metabolism and chondrocyte apoptosis.

Conclusion

Multiple signaling pathways were involved in the pathological process of TMJ OA. New therapeutic strategies, such as stem cell application, gene editing and other techniques may be utilized for TMJ OA treatment.

The translational potential of this article

TMJ OA is a most important subtype of TMJ disorders and may lead to substantial joint pain, dysfunction, dental malocclusion, and reduced health-related quality of life. This review article summarized current findings of signaling pathways involved in TMJ OA, including Wnt/β-catenin, TGF-β and BMP, Indian Hedgehog, FGF, NF-κB, and Notch pathways, to better understand the pathological mechanisms of TMJ OA and define the molecular targets for TMJ OA treatment.

[Radiological analysis of size of bone elements of the temporomandibular joint in children and adolescents with class II malocclusion]

BACKGROUND

The aim of the study was to assess the ratio of bone elements of the temporomandibular joint (TMJ) in children and adolescents with distal occlusion according to cone-beam computed tomography (CBCT).

MATERIAL AND METHODS

CBCT of the TMJ was analyzed in 121 patients aged 12-18 years, which were divided into two age groups: group I - children aged 12-15 years (62 cases in total, of which 47 patients with distal occlusion and 15 patients with physiological occlusion) and II group - adolescents aged 15-18 years (59 cases, of which 48 patients with distal occlusion and 11 patients with physiological occlusion). CBCT of the temporomandibular joint was performed by the standard method in the position of habitual occlusion and maximally open mouth. The size of the TMJ joint space in the anterior, upper and posterior sections was determined by the method of Rabukhina N.A., the analysis of the ratio of the bone elements of the TMJ was carried out using the Craniometry program.

RESULTS

The size of the joint space and the angle β of the temporomandibular joint in the anterior section on the right and left in children aged 12-15 with distal occlusion is increased compared to children with physiological occlusion in the position of habitual occlusion. In adolescents 15-18 years old with distal occlusion, the size of the TMJ joint space is increased in the anterior section on the right and left and reduced in the posterior section on the right, angle α is reduced on the right and left, angle β is reduced on the right, angle γ is increased on the right compared to adolescents with physiological occlusion. The revealed deviations indicate the presence of violations in the ratio of the bone elements of the TMJ, which are aggravated with age.

CONCLUSION

Analysis of the results obtained during CBCT in children and adolescents allows us to correct the plan of orthodontic treatment and predict its results.

Relationship between horizontal condylar angle and radiographically detectable morphological changes of the condyle in asymptomatic and symptomatic patients with TMD

Background

The relationship between horizontal condylar angle (HCA) measurements and radiographically detectable morphological changes of the condyle in patients with temporomandibular disorder (TMD) is an area of controversy in dentistry.

Aim

This study sought to determine the effect of the HCA on radiographically morphological changes in the condyles of asymptomatic and symptomatic patients with TMD.

Material & methods

Cone beam computed tomography (CBCT) scans were used of patients with 146 temporomandibular joints (TMJ) with and without symptoms of TMD. The reconstructed axial plane was adjusted to depict the condyle in maximum width. The HCA was established and measured as the angle formed between the condylar long axis intersecting with the coronal plane. Each condyle long axial was determined independently from the other joint by two oral and maxillofacial radiologists. The average of the readings from the two examiners was used for statistical analysis.

Results

Based on the clinical symptoms, the mean of the HCA in the symptomatic joint was 27.69°, which was slightly greater than the angle measured in asymptomatic patients of 25.6°; however, this was not a statistical difference. No significant differences existed in the mean of the HCA between the joint with and without radiographic arthritic findings in both groups. In both groups, none of the arthritic findings manifested in the affected joint that had influenced the HCA.

Conclusion

The HCA was increased in the symptomatic group but had no direct influence on joint's morphological changes in the asymptomatic and symptomatic patients.

Functional, physical and psychosocial impact of degenerative temporomandibular joint disease

OBJECTIVES

This study evaluated the functional, physical and psychosocial impacts of TMJ degenerative joint disease (DJD). The bearing of TMJ osteoarthrosis/osteoarthritis and early/late TMJ DJD on oral health-related quality of life (OHRQoL) were also compared.

METHODS

Participants were enrolled from a TMD/oro-facial pain centre. Those diagnosed with intra-articular conditions based on the Diagnostic Criteria for Temporomandibular disorders (DC/TMD) were subjected to CBCT assessment and categorised into four discrete groups: NN-no TMJ DJD and no arthralgia; NA-no TMJ DJD with arthralgia; TO-TMJ osteoarthrosis; and TR-TMJ osteoarthritis. The TO/TR groups were subdivided into early/late TMJ osteoarthrosis (EO/LO) and osteoarthritis (ER/LR). OHRQoL was examined using the OHIP-TMD, and data were appraised with the Kruskal-Wallis/Mann-Whitney U tests (α = 0.05).

RESULTS

The study participant (n = 358) had a mean age of 31.85 ± 12.39 years (85.6% women). Frequencies of the TMD groups were as follows: NN-23.2%; NA-27.1%; TO-19.0%; and TR-30.7%. Participants with TR/NA had significantly worse OHRQoL than those with TO/NN. Additionally, participants with ER/LR reported significantly poorer OHRQoL than their counterparts with EO/LO. For all TMD groups and TMJ DJD subgroups, the psychological discomfort domain was generally the most impaired. Differences in global OHIP scores were significant between participants with and without arthralgia (i.e., NA-NN, ER-EO and LR-LO).

CONCLUSIONS

The presence of TMJ pain appeared to impair OHRQoL more than the severity of TMJ DJD. As psychological domains were most impacted, psychosocial care should be incorporated when managing patients with painful TMJ DJD.

Effect of 17β-estradiol on the proliferation of condylar chondrocytes

OBJECTIVES

To study the effects of 17β-estradiol (E2) on the regulation of the proliferation of condylar chondrocytes and provide a preliminary discussion on the role of phosphorylate-mammalian target of rapamycin (p-mTOR) in this regulatory process.

METHODS

Condylar chondrocytes were isolated from 6-week-old female rats for primary culture. Drug treatment with different concentrations of E2 and/or rapamycin (RAPA) was carried out on second-generation cells. Cell Counting Kit 8 was used to measure the cell viability of condylar chondrocytes after culture for 24, 48, or 72 h, and reverse transcription-polymerase chain reaction (RT-PCR) was applied to detect the relative gene expression of estrogen receptor alpha (ERα), estrogen receptor beta (ERβ), collagen type Ⅱ (COLⅡ), autophagy-related gene 6 (Beclin-1), and autophagy-related gene 5 (ATG-5). Western blot was employed to determine the relative protein expression of ERα, ERβ, Beclin-1, lipid-modified light chain 3B (LC3-Ⅱ), and p-mTOR.

RESULTS

E2 could significantly promote the proliferation of chondrocytes cultured in vitro, and maximum promotion was achieved at a concentration of 10^-8 mol·L^-1. RAPA could significantly inhibit cell proliferation. E2 at aconcentration of 10^-8 mol·L^-1 could greatly improve the gene expression levels of ERα and COLⅡ (P<0.01) with the protein levels of ERα and p-mTOR (P<0.05), and decrease the gene expression levels of Beclin-1 and ATG-5 (P<0.05) with the protein levels of Beclin-1 and LC3-Ⅱ (P<0.05). RAPA could also enhance the relative protein expression of Beclin-1 and LC3-Ⅱ (P<0.01), and reduce the expression of p-mTOR (P<0.01). Treatment with the ERα antagonist significantly reduced the expression of p-mTOR in cells (P<0.01).

CONCLUSIONS

At a concentration of 10^-8 mol·L^-1, E2 could effectively activate the phosphorylation of mTOR through the ERα-p-mTOR pathway, inhibit cell autophagy, and promote the proliferation of condylar chondrocytes.