The influence of COVID-19 on temporo-mandibular disorders.

Temporomandibular disorders are multi-factorial conditions affected by psychological, biomechanical, and neuromuscular factors. Stress and anxiety experienced during the pandemic are capable of influencing and aggravating temporomandibular disorders and orofacial pain. The study aimed to analyze whether the coronavirus infection can directly affect these diseases. All participants were asked to complete the Pain Screener and Patients Health Questionnaire and were assigned to Group I: healthy participants and Group 2: participants with existing complaints. In group II participants filled the questionnaires twice the Temporomandibular Disorders Symptom Questionnaire and Graded Chronic Pain Scale. The first time to self-report the severity of chronic pain before COVID-19 (T1 timeline) and the second time- to self-report the level of pain after COVID-19 infection (T2 timeline). Totally 150 participants were included in the study. In group II the difference between T1 and T2 timeline was significant for the level of average pain (p = 0.022) and highest facial pain (p = 0.043); Difference in level of interference of daily activities (p > 0.05), recreational activities (p > 0.05) and ability to work (p > 0.05) was statistically not significant. Graded chronic pain status was the same "Grade I" for T1 and T2 timeline. There was no statistically significant difference in stress level between group I and II.

Mesenchymal stem cell transplantation attenuates growth of chemotherapy treated oral squamous cell carcinoma in an animal model.

BACKGROUND: Recent studies have demonstrated mesenchymal stem cell migration toward tumor locations. When applied locally, MSCs interact with the locally residing host cells. The mechanisms behind this are still unclear. We aimed to detect the possible action mechanisms of MSCs on the in vivo growth of primary human oral squamous cell carcinoma. METHODS: In mouse model of OSSC, chemotherapy with Cisplatin was done beginning from 9 day of tumor visualization. 3 weeks after tumor cell injection cultivated MSCs were administrated in tail vein or directly intra-tumorally. Animals underwent surveillance and afterward were sacrificed. Tumor growth was measured. MSCs biodistribution was assessed with bioluminescent analysis. Tumor tissues were tested morphologically and immunohistochemically for angiogenesis, hypoxia status, and cell apoptosis. RESULTS: In the group treated with Cisplatin in combination with mesenchymal stem cell injection, the average size of the tumor was 98.9 ± 7.65 mm3 . In the experimental group, tumor tissues were less outlined and the presence of necrotic areas and connective tissue basal layers was detected. Immunohistochemical surveys with CD31 and anti-carbonic anhydrase 9 demonstrated strongly developed micro-vessel structures and small isles of hypoxia in the tumor tissues. TUNEL assay revealed in the same group that tumor tissues were mostly comprised of apoptotic cells. Viable cell communities presented as small isles. CONCLUSION: The study demonstrates that intra-tumorally injected MSCs, combined with Cisplatin, leads to a minimal hypoxia status and increased apoptotic activity in tumor tissues, compared with the control group. This finding can be explained with better distribution of Cisplatin due to increased angiogenesis.

Benign osteoblastoma of the mandible in a 12-year-old female: A case report.

Benign osteoblastoma refers to a benign tumor of the bone. Osteoblastoma most commonly affects the vertebrae and long tubular bones, however, in rare cases is observed in the facial bones. The current study presents the case of a 12-year-old female patient with a tumor in the mandibular body. Radiological imaging revealed a lesion with regular contours. The lesion was radically resected and histological analysis of the specimen demonstrated features that are typical of a benign osteoblastoma. The consequential defects of the jaw were reconstructed using titanium implants and autologous bone transplantation. The patient remains disease free subsequent to a five-month follow-up period. The aim of the present report is to present a rare case of benign osteoblastoma of the mandible. This study demonstrated that correct diagnosis and complete surgical excision are important to reduce the risk of recurrence of a benign osteoblastoma.