Estudio mediante resonancia magnética de la posición y morfología del disco articular en pacientes con sintomatología temporomandibular

Résumé

Objective: The aims of this study are to demonstrate if articular disc displacement is determinant for degenerative changes, assesses if disc subluxation is associated with structural changes in the jaw condyle and how can even change the translation movement of the condyle, and determine whether depending on the subluxation of the disc vary the pain, clicking and blockage of the temporomandibular joint. We have also studied if disc subluxation can modify the position of the contralateral articular disc, as well as trigger clinical symptoms and structural changes in the opposite joint. We have as well examined if disc displacement with reduction could be responsible for structural changes in the disc and in the mandibular condyle, and if all these findings are different in both sexes. And finally, we want to analyze whether the alteration of the normal position of the disc affects the diameters of the condylar position in the MRI studies. Matherial and methods: We have designed a retrospective cross-sectional observational study to achieve the objectives described above, selecting 159 patients who came to the Central Hospital of the Defense Gómez Ulla radiology department describing signs or symptoms related to the temporomandibular joint. Most patients are referred from maxillofacial surgery and odontology departments, and a minority from otolaryngology department. The patient data collection process takes place between 2012 and 2015. Exclusion criteria were those patients with a personal history of mandibular fractures, tumor pathology, acute trauma, pacemaker or any other contraindication to perform an MRI, or those who did not endure the exploration due to claustrophobia. Results: The study included 159 patients, 136 women and 23 men. The average age was 47 years in both groups (slightly lower among males). Clear results have been obtained about the relationship between disc subluxation and disc degeneration. However, final results have not been so conclusive regarding the symptomatology: pain and clicking seem to be related to the position of the disc in the left TMJ studied, while on the right side we have found statistically significant results only regarding the relationship with the mandibular blockage. The relationship between disc subluxation and condylar remodeling (flattening and osteophyte formation) is also clearly significant, as well as the obvious decrease of the condylar movement. Another relevant factor is that disc displacement is related with degenerative changes and alterations in the position of the contralateral articular disc. On the opposite, it does not seem to influence the symptomatology of the contralateral side. Likewise, the diameters obtained in our study population, comparing patients with and without disc subluxation, are statistically significant. Nevertheless, disc displacement with reduction does not seem to be directly related to degenerative changes in the articular disc, even though protects from degenerative changes in the mandibular condyle as the osteophyte formation. Finally, disc displacement with or without reduction it that not seem to be related (once again) to TMJ symptomatology. Conclusions: The alteration of the position and morphology of the temporomandibular joint disc determine degenerative changes both in the disc itself and in the rest of the joint structures. The symptomatology (pain, clicking and blockage) is associated with disc displacement, although in some cases we must take into account other factors to explain it. The position of the disc is determinant in the movement of the mandibular condyle. The temporomandibular joints work as a single functional complex, and degenerative changes in one of them affect the contralateral one. Disc subluxation (with or without reduction) accelerates the degenerative changes of the disc. There are significant differences between both sexes regarding the pathology of the temporomandibular joint (prevalence in women), although the cause of this disparity is not yet well known. The diameters obtained from the condylar position in the magnetic resonance imaging studies could be used in future lines of research, with the aim of assessing the possibility of being extrapolated to computerized tomography studies (CT scans). In this way, we could achieve a more accurate diagnosis in clinical practice.