Overload of the Temporomandibular Joints Accumulates γδ T Cells in a Mouse Model of Rheumatoid Arthritis: A Morphological and Histological Evaluation

Recently, it has been reported that γδ T cells are associated with the pathology of rheumatoid arthritis (RA). However, there are many uncertainties about their relationship. In this study, we investigated the morphological and histological properties of peripheral as well as temporomandibular joints (TMJ) in a mouse model of rheumatoid arthritis with and without exposure to mechanical strain on the TMJ. Collagen antibody-induced arthritis (CAIA) was induced by administering collagen type II antibody and lipopolysaccharide to male DBA/1JNCrlj mice at 9−12 weeks of age, and mechanical stress (MS) was applied to the mandibular condyle. After 14 days, 3D morphological evaluation by micro-CT, histological staining (Hematoxylin Eosin, Safranin O, and Tartrate-Resistant Acid Phosphatase staining), and immunohistochemical staining (ADAMTS-5 antibody, CD3 antibody, CD45 antibody, RORγt antibody, γδ T cell receptor antibody) were performed. The lower jawbone was collected. The mandibular condyle showed a rough change in the surface of the mandibular condyle based on three-dimensional analysis by micro-CT imaging. Histological examination revealed bone and cartilage destruction, such as a decrease in chondrocyte layer width and an increase in the number of osteoclasts in the mandibular condyle. Then, immune-histological staining revealed accumulation of T and γδ T cells in the subchondral bone. The temporomandibular joint is less sensitive to the onset of RA, but it has been suggested that it is exacerbated by mechanical stimulation. Additionally, the involvement of γδ T cells was suggested as the etiology of rheumatoid arthritis.

Intraoperative Positioning in Maxillofacial Trauma Patients With Cervical Spine Injury – Is It Safe? Radiological Simulation in a Healthy Volunteer

Introduction Cervical spine (C-spine) injury is present in up to 10% of patients with maxillofacial fractures. Uncertainty over the status of the C-spine and permitted head movements may delay maxillofacial surgical intervention, resulting in prolonged patient discomfort and return to oral nutrition, reducing quality of life. This study aimed to investigate the effects on the C-spine of positioning patients for maxillofacial procedures by simulating intraoperative positions for common maxillofacial procedures. Methods Magnetic resonance imaging was used to assess the effects of head position in common intraoperative configurations – neutral (anterior mandible position), extended (tracheostomy position) and laterally rotated (mandibular condyle position) on the C-spine of a healthy volunteer. Results In the tracheostomy position, maximal movement occurred in the sagittal plane between the cervico-occipital junction and C4–C5, as well as at the cervico-thoracic junction. Minimal movement occurred at C2 (on C3), C5 (on C6) and C6 (on C7). In the mandibular condyle position, C-spine movements occurred in both rotational and sagittal planes. Maximal movement occurred above the level of C4, concentrated at atlanto-occipital and atlanto-axial (C1–2) joints. Conclusion Neck extension is likely to be relatively safe in injuries that are stable in flexion and extension, such as odontoid peg fracture and fractures between C5 and C7. Head rotation is likely to be relatively safe in fractures below C4, as well as vertebral body fractures, and laminar fractures without disc disruption. Early dialogue with the neurosurgical team remains a central tenet of safe management of patients with combined maxillofacial and C-spine injuries.

Is the Mandibular Condyle Involved in Medication-Related Osteonecrosis of the Jaw? Audit of a Single Tertiary Referral Center and Literature Review

Background: Medication-related osteonecrosis of the jaw (MRONJ) may manifest as exposed mandible bone. Recent reviews of the incidence of MRONJ report primarily as exposed cortical bone of the mandibular body, ramus, and symphysis with no reports of condylar involvement. Objective: The aim of this study is to analyze the topographical incidence of MRONJ, comorbidities, demographics data, and clinical characteristics of patients diagnosed with MRONJ between 2014 and 2019 in the Maxillo-Facial Surgery Department University of Campania “Luigi Vanvitelli”, and compare these results with published reports. Methods: Data on 179 patients were collected for the study, including gender, age, underlying malignancy, medical history, and specific lesion location-identifying premaxilla and posterior sectors area involvement for the maxilla and symphysis, body, ramus, and condyle area for the mandible. A literature review was performed in order to compare our results with similar or higher sample sizes and find if any condylar involvement was ever reported. The research was carried out on PubMed database identifying articles from January 2003 to November 2020, where MRONJ site distribution was discussed, and data were examined to scan for condylar localization reports. Results: 30 patients had maxillary MRONJ, 136 patients had mandibular MRONJ, and 13 patients had lesions located in both maxilla and mandible. None of the patients reported condylar involvement, neither as a single site nor as an additional localization. Literature review results were coherent to our findings showing no mention of condylar MRONJ. Conclusion: Results do not show reports of condylar involvement in MRONJ. Although the pathophysiology of the disease has not been fully elucidated, two possible explanations were developed: the first one based on the condyle embryogenetic origin; the second one based on the bisphosphonate and anti-resorptive medications effects on the different vascular patterns of the mandible areas.

Progressive systemic sclerosis with unilateral osteolysis of the mandible: a unique case report and review

Objectives: This case report is aimed to discuss case findings of Progressive Systemic Sclerosis (PSS), an overview of the characteristics in the form of osteolysis on one side of the mandible, and a theoretical review. Case Report: A 30-year old male patient came to an oral surgeon after tooth extraction. Clinical extraoral examination revealed hyperpigmentation on the right side of the face. A radiological study showed widening periodontal space on posterior teeth, and the angles of the mandibular arch, the jaw branch and the mandibular condyle neck were dissolved in the form of bone resorption. Conclusion: Characteristics of Progressive Systemic Sclerosis (PSS) in radiographs appear in the form of expansion of the periodontal space and osteolysis of the mandibular angle, branch, and even condyle. This disease is caused by an autoimmune disease that affects the entire body, but it can manifest on one side of the body.

A modified endaural approach to the fractured condyle: a clinical case report

The authors present a modified endaural incision with a caudal extension for surgical access to the mandibular condyle. The approach combined the advantages of good scar cosmesis and sufficient access to the surgical site for optimal placement of the osteosynthesis with lesser risk of nerve damage.

The Influence of the Mandibular Chin Angle on the Occurrence of Mandibular Condylar Fracture: A Retrospective Study

Background. Condylar fractures are commonly associated with symphysis/parasymphysis fractures. Condylar fractures have been attributed to direct and indirect traumatic forces, the direction and magnitude of the forces, and the condylar anatomy. The chief aim of this study was to determine the association between the newly defined mandibular chin angle and the occurrence of condylar fractures. Materials and Methods. A retrospective study was conducted to analyze two-dimensional computed tomography (2D CT) scans of patients with a history of chin trauma. The outcome was a symphysis/parasymphysis fracture with or without fracture of the mandibular condyle. The Mediff InstaRISPACS web-based platform was used to measure the chin angle. The cerebral aqueduct of Sylvius in the corresponding 2D CT midsagittal image was the standard reference plane to measure the chin angle. The SPSS Version 20 (IBM Corp, Armonk, NY) was used for data analysis. Results. The sample size included 120 2D CT scans of patients with symphysis/parasymphysis fractures (60 associated with condylar fractures and 60 without condylar fractures). The mean chin angle in the group without condylar fracture was 133.35 ± 3.87°, which was approximately 15° lesser than in the condylar fracture group (mean, 148.56 ± 5.49°), and these findings were statistically significant P < 0.05 . Conclusion. Individuals with a high chin angle are potentially at a higher risk of sustaining associated condylar fractures.

A Case of Synovial Chondromatosis of Temporomandibular Joint with Numerous Loose Bodies

Here, we report a case of synovial chondromatosis of the temporomandibular joint (TMJ) with numerous loose bodies. A 56-year-old woman was examined in the oral surgery department for trismus and pain in the left TMJ when opening the mouth. Imaging indicated TMJ synovial chondromatosis, and the patient was referred to our department for further examination. Her facial features were symmetrical, and no occlusal abnormalities were found. The maximum mouth opening was 30 mm, and movement of the left mandibular condyle was restricted and accompanied by pain and joint sounds. Panoramic radiography showed deformation of the left mandibular condyle and radiopaque lesions surrounding it. Computed tomography showed numerous small granules around the left mandibular condyle, some of which were calcified. Magnetic resonance imaging showed anterior disc displacement without reduction in the left TMJ and hypointense lesions on T2-weighted images. Bone scintigraphy showed an accumulation in the area of the left TMJ. Based on the diagnosis of the left TMJ synovial chondromatosis, the lesions were removed, and plastic surgery on the mandibular condyle was performed under general anesthesia. We removed 386 white loose bodies. Histopathologically, the loose bodies were consistent with synovial chondromatosis lesions. The postoperative course was uneventful, with no recurrence or TMJ dysfunction approximately 5 years after the surgery, indicating that open surgery is the best course of intervention in such cases.