Condylar long axis and articular eminence in MRI in patients with temporomandibular disorders

Relation between Condyle Horizontal Angle and Intercondylar Angle with Disc Displacement in Patients with Temporomandibular Joint Disorders: An MRI Evaluation

Background

Internal derangement (ID) is the most common cause of temporomandibular disorders (TMDs) and extensively affects the articular disc function. The anterior disc displacement is among the most important findings in ID. Knowledge about the etiology of this condition is imperative, and the role of structural parameters in the development of TMDs has not been well evaluated.

Objectives

This study aimed to assess the relationship between condylar angulation and intercondylar angle with anterior disc displacement in patients with TMD using magnetic resonance imaging (MRI).

Materials and Methods

This case-control study evaluated 31 temporomandibular joints with internal derangement and 57 normal joints. The data retrieved from MRI included disc position in the open mouth (normal, anterior disc displacement with a reduction (DDWR) and without reduction (DDWOR), and posterior displacement (PD)), horizontal condylar angle categorized as normal (10 to 30° angle) and abnormal (<10° and >30°), and intercondylar angle. Chi-square test, T-test, and Fisher's exact were done to assess the relationship between horizontal condylar angle and intercondylar angle in patients with TMDs with DDWR and DDWOR compared with the control group.

Results

Patients with DDWR and DDWOR had higher odds of abnormal horizontal condylar angle, particularly >30° angle, which was a significant correlation (odds ratio of 0.19 and 8.3, respectively). The intercondylar angle in the patients with disc displacement was significantly smaller compared to the control group.

Conclusion

Disc displacement was correlated with abnormal horizontal angle (particularly < 30) and smaller intercondylar angle compared with the control group.

Skeletal Divergence and Condylar Asymmetry in Patients with Temporomandibular Disorders (TMD): A Retrospective Study

INTRODUCTION

This study was aimed at evaluating the association between vertical skeletal patterns, condylar height symmetry, and temporomandibular disorders in adults.

METHODS

The study sample consisted of 200 patients (ages 18-30 years old) retrospectively recruited: 100 with temporomandibular disorders (TMD) and 100 without TMD (control), diagnosed by Diagnostic Criteria for the Temporomandibular Disorders (DC/TMD). For each subject, skeletal divergence was assessed on lateral cephalograms, and condylar height symmetry was evaluated by orthopantomography (Habets' method).

RESULTS

Subjects with temporomandibular disorders showed a strong association with condylar asymmetry (p < 0.0001) and, for the skeletal pattern variables, hyperdivergence (p < 0.001). A correlation with the female sex was also found (p < 0.04), while there was no difference in terms of age in the 2 groups (p > 0.29).

CONCLUSIONS

Although it does not imply a direct cause-and-effect relationship, the present study suggests condylar asymmetry and hyperdivergent skeletal pattern are more likely to be associated with a higher risk of temporomandibular disorder joint diseases in adult patients.

Is There an Association between Temporomandibular Disorders and Articular Eminence Inclination? A Systematic Review

(1) Background: In order to determine the correlation between the inclination of articular eminence (AEI) and the development of temporomandibular disorders (TMDs), a systematic review was performed. (2) Methods: A systematic literature research was conducted between 1946 and January 2020, based on the following electronic databases: PubMed, Cochrane Library, Embase, Medline, Scope, SciELO, and Lilacs. Observational studies, analytical case-control studies, and cohort studies written in English were identified. The articles were selected and analyzed by two authors independently. The PICO format was used to analyze the studies and the Newcastle-Ottawa Scale (NOS) was used to verify the quality of the evidence. (3) Results: Sixteen articles were included in this review, ten case-control studies and six cohort studies. Eight articles (50%) established a positive relation between AEI and TMDs and eight (50%) did not. The scientific quality was medium-low, mainly influenced by the exposure to the risk of bias and the lack of clinical methods with adequate consistency and sensitivity on the diagnosis of TMDs. (4) Conclusions: It is controversial to establish a causal relationship between the TMDs and the AEI in the field of stomatology, due to limited and inconclusive evidence. However, it is suggested that the AEI defined by some specific methods may be associated with some special pathological stages of TMDs. High-quality prospective studies are required to draw any definitive conclusions.