Oral squamous cell carcinoma (OSCC) is one of the most common malignances. In epithelial-mesenchymal transition (EMT), epithelial cells switch to mesenchymal-like cells exhibiting high mobility. This migratory phenotype is significant during tumor invasion and metastasis. Objective: The aim of this study is to evaluate the expression of the EMT markers E-cadherin, N-cadherin and vimentin in OSCC.Material and Methods : Immunohistochemical detection of E-cadherin, N-cadherin and vimentin was performed on 20 OSCC samples. Differences in the expression of each protein at the invasive front (IF) and in the central/superficial areas (CSA) of the tumor were assessed. Differences in the expression of each protein at the IF of both histologically high- and low-invasive OSCCs were evaluated. Associations among expression of proteins at the IF were assessed. Correlations between the expression levels of each protein at the IF and the tumor stage and clinical nodal status were also evaluated.Results : Reduced expression of E-cadherin was detected in 15 samples (75%). E-cadherin expression was reduced at the IF when compared to the CSA and in high-invasive tumors when compared to low-invasive tumors. All samples were negative for N-cadherin, even though one sample showed an inconspicuous expression. Positive expression of vimentin was observed in 6 samples (30%). Nevertheless, there was no difference in vimentin expression between the IF and the CSA regions or between the low- and high-invasive tumors. Furthermore, no association was observed among protein expression levels at the IF. Finally, no correlations were observed between each protein’s expression levels and tumor stage or clinical nodal status.Conclusions : Reduced E-cadherin expression at the IF and its association with histological invasiveness suggest that this protein is a noteworthy EMT marker in OSCC. Although vimentin was also detected as an EMT marker, its expression was neither limited to the IF nor was it related to histological invasiveness.

The Calcifying Odontogenic Cyst (COC) is a simple cyst lined by ameloblastoma-like epithelium with ghost cells. The peripheral COC is a rare lesion and few reports have been published considering its clinical and histopathological features. This article aimed to report on a case of a peripheral COC, discussing its clinical, imaginological and histopathological features. A 9-year-old male patient presented a 10x5 mm painless nodule in the palatal mucosa of the left central incisor. Panoramic, occlusal and periapical radiographs did not show alterations. A computed tomography exam showed a slight soft tissue swelling located in the palatal mucosa of the left maxillary central incisor. An excisional biopsy was performed. The histopathological analysis showed a cystic lesion adhered to an oral mucosa fragment and lined by an ameloblastoma-like epithelium with ghost cells. The diagnosis of peripheral COC was established and the patient has been disease-free for 5 years. Although rare, peripheral COC is an important lesion that should be considered as a differential diagnosis of gingival hyperplastic lesions. Key words:Calcifying odontogenic cyst, odontogenic tumors, peripheral calcifying odontogenic cyst.

The SARS-CoV-2 virus, which causes COVID-19, can be transmitted directly, by contact and by air. In this context, dental practice presents risks of contamination, as it involves very close communication between professional and patient, frequent exposure to saliva, blood, and other body fluids, as well as aerosols and droplets generated in oral procedures. Objective: Aiming to contribute to increase the professionals and their patients’ safety, the purpose of this review was to conduct a brief overview of SARS-CoV-2 infection, its pathogenesis, diagnosis, transmission, and control routes in dental practice, in addition to recommendations for clinical care. Material and methods: The bibliographic search was performed using the descriptors “COVID-19”, “security measures”, and “dental care” in the databases: PubMed, MEDLINE, Latin-American and Caribbean Health Sciences (Lilacs) and Scientific Electronic Library Online (SciELO), without language restriction and published between 2000 and 2020. Results: The review of the scientific literature revealed that a careful anamnesis of the patient should be performed before any dental treatment. However, in the face of the current pandemic, if it is not possible to postpone dental intervention, procedures should be performed following recommendations that aim to decrease the generation of aerosols and droplets seeking to increase individual protection. Conclusion: According to the current context and scenario, the universal measures of infection control must be maintained, reviewed, and reinforced during any dental care. Further studies are needed to investigate and validate additional protective measures not only for dental professionals, but also for their patients.