Histological study of the extratympanic portion of the discomallear ligament in adult humans: a functional hypothesis

Otological symptoms in patients with rheumatoid arthritis of the temporomandibular joint

OBJECTIVE

The aim of the current study was to describe the pattern of otological symptoms in patients with rheumatoid arthritis (RA), having clinical temporomandibular joint (TMJ) involvement. This issue had not been previously addressed.

METHODS

A questionnaire and examination findings protocol was applied for 141 patients with RA and 141 control subjects.

RESULTS

Otological symptoms (otalgia, hearing loss, tinnitus, and vertigo), all had a significantly higher incidence in RA patients, compared to control subjects (P = .001).

CONCLUSION

The onset and maintenance of otological symptoms in patients with TMJ involvement by RA probably result from peripheral, as well as central nervous system alterations in sensory stimuli programming.

Arthroscopic osteoplasty of the medial and anteromedial wall of temporomandibular joint: surgical technique and anatomical considerations

The anterior displacement of the articular disc is the most frequent cause of pathological alterations in the TMJ. Although it is an extremely common pathology, there is no certainty about the aetiopathogenesis of this disease. The main aim of the present report is to describe new anatomical findings that could help clarifying the aetiopathogenesis of this disease and determine a typology of treatment based on the cause of the disease. All the operative records of patients who underwent arthroscopic osteoplasty of the medial TMJ wall in our centre from January 2021 to September 2021 were reviewed and analysed to identify specific anatomical features observed in every procedure. Fifty-two joints were included for analysis in this study. Twenty-two joints were classified as Wilkes stages II-III and 30 as Wilkes stages IV-V. The most common complication observed in our sample was the dysaesthesias found in the temporal and preauricular regions. Other complications observed were frontal branch paresis (n = 2), intraoperative bleeding (n = 1), and postoperative malocclusion (n = 1). The compression of the superior head of pterygoid lateral muscle (SPLM) on the medial bony wall and the consequent muscle atrophy could be key for the aetiology of the anterior TMJ disc displacement. Therapeutic actions on the osseous and muscular component in this anatomical area could improve the outcomes of patients affected by TMJ internal derangement. A meticulous dissection of the fascia of the superior fascicle of the lateral pterygoid muscle allows a remodelling of the bone surfaces with minimal complications.

Temporomandibular disorder: A previously unreported complication of chronic suppurative otitis media

OBJECTIVE

The aim of the current clinical study was to test the hypothesis that chronic suppurative otitis media (CSOM) might be significantly associated with signs of temporomandibular joint (TMJ) internal derangement.

METHODS

The study involved 79 patients with CSOM and 79 control subjects. The TMJ was clinically examined in both groups.

RESULTS

Signs of internal derangement of the TMJ(s) were found in 67.1% of CSOM patients versus 26.6% of control subjects (p = .001).

CONCLUSION

CSOM may be associated with the extension of the inflammatory process into the TMJ, thereby predisposing to internal derangement of the joint.

Microscopic reconstruction and immunohistochemical analysis of discomalleolar ligament

Discomalleolar ligament represents the vestiges of the primitive lateral pterygoid muscle which penetrates in the caudal end of Meckel's cartilage; during the development of newborn, the petrotympanic fissure close almost completely leaving inside the discomalleolar ligament. After entering in tympanic cavity, some fibers of the discomalleolar ligament insert to walls of cavity, other fibers continue with the lateral margin of the anterior ligament and insert in the neck of malleus; in contrast, other Authors demonstrated that discomalleolar ligament is an independent structure inserted in proximity of the neck of the malleus. Although the discomalleolar ligament can be considered as a structure of clinical importance, it is not described by anatomy textbooks. Moreover, it is likely that important correlations between temporomandibular diseases and otological symptoms exist. We have studied discomalleolar ligament submitting the specimens to the 3D volume rendering technique, light microscopy, reconstructing a wide light microscopic fields to analyze the real connection between retrodiscal connective tissue and middle ear, and immunofluorescence methods in order to analyze the consistence of ligament. We have shown two types of connections between TMJ and ear: first, with external acoustic meatus and, second, with middle ear through discomalleolar ligament. The different insertion represents a strong support in order to demonstrate that the TMJ disorders can determine variations of tension that are transmitted on the tympanic membrane provoking tinnitus in according to clinical features. Then, we propose that it is necessary to mention, also in anatomy textbook, the discomalleolar ligament as ligament distance of TMJ.

An Investigation of the Morphology of the Petrotympanic Fissure Using Cone-Beam Computed Tomography

Objectives

The purpose of the present study was: a) to examine the visibility and morphology of the petrotympanic fissure on cone-beam computed tomography images, and b) to investigate whether the petrotympanic fissure morphology is significantly affected by gender and age, or not.

Material and Methods

Using Newtom VGi (QR Verona, Italy), 106 cone-beam computed tomography examinations (212 temporomandibular joint areas) of both genders were retrospectively and randomly selected. Two observers examined the images and subsequently classified by consensus the petrotympanic fissure morphology into the following three types: type 1 - widely open; type 2 - narrow middle; type 3 - very narrow/closed.

Results

The petrotympanic fissure morphology was assessed as type 1, type 2, and type 3 in 85 (40.1%), 72 (34.0%), and 55 (25.9%) cases, respectively. No significant difference was found between left and right petrotympanic fissure morphology (Kappa = 0.37; P < 0.001). Furthermore, no significant difference was found between genders, specifically P = 0.264 and P = 0.211 for the right and left petrotympanic fissure morphology, respectively. However, the ordinal logistic regression analysis showed that males tend to have narrower petrotympanic fissures, in particular OR = 1.58 for right and OR = 1.5 for left petrotympanic fissure.

Conclusions

The current study lends support to the conclusion that an enhanced multi-planar cone-beam computed tomography yields a clear depiction of the petrotympanic fissure's morphological characteristics. We have found that the morphology is neither gender nor age-related.

Analysis by Light, Scanning, and Transmission Microscopy of the Intima Synovial of the Temporomandibular Joint of Human Fetuses during the Development

Objective. To characterize morphologically and ultrastructurally using light microscopy, the scanning electron microscopy and transmission electron microscopy the intima synovial of the temporomandibular joint (TMJ) of human fetuses between the 10th and the 38th week of development. Materials and Methods. The TMJ was dissected bilaterally in 37 human fetuses belonging to the Institute of Embryology of the University Complutense of Madrid and of the Federal University of São Paulo. Results. The outcome by light microscopy showed the morphology of the TMJ and that the formation of inferior joint cavity precedes the superior joint cavity and the presence of blood vessels in the synovial. Conclusion. By scanning and transmission electron microscopy we observed the presence of two well-defined cell types in the intima layer of synovial of the TMJ of human fetuses, macrophage-like type A cell and fibroblast-like type B cell, and the presence of the a third cell type, defined by the name of intermediate lining cell in the intima layer of the synovial.