In less than four months, an unprecedented pandemic changed the world scenario, closing institutions and commerce, paralyzing sports championships, blocking frontiers, and putting almost all populations in a house quarantine regimen. Immunocompromised patients are within the high-risk group to severe outcomes from COVID-19. However, there is no clear evidence of the association between impaired immune host status and complications from SARS-CoV-2 infection so far. The virus is transmitted by inhalation or direct contact with infected secretions, and therefore the dental office is a highly susceptible environment for such transmission. Here, we review the literature and discuss immunological COVID-19 related issues. We also make suggestions for immunocompromised patients’ support in this new emerging context of clinical dental practice. Until comprehensive findings are published, individuals with impaired immunity should be considered as high-risk. Cross infection control procedures for the clinical care of immunocompromised patients should follow the same guidelines that are being proposed for immunocompetent ones. However, during the active outbreak, people under immunosuppressive conditions should not receive elective procedures, even if they do not have symptoms or exposure history to COVID-19, and in case of emergence, care must be done in a separate airborne room. In the pos-pandemic phase, the dental care general recommendations should be the same for all subjects. Changes in the current guidelines have been proposed to SARS-CoV-2 infection control in order to provide the best and safe dental practice. However, they still need to be validated by future studies.

Oral squamous cell carcinoma (OSCC) is the sixth most common type of cancer globally. While smoking is a key risk factor, rising cases in non-smokers highlight the need to explore other factors like diet. This scoping review aims to deepen the evidence on the relationship between OSCC and diet, following PRISMA-ScR guidelines, and was registered on Open Science Framework. Searches were performed in four electronic databases: MEDLINE, Embase, Web of Science, and Lilacs, without date or language restrictions. Studies were evaluated, extracted, and compiled in a narrative table. Seventeen studies with 10,954 patients were analyzed. Most patients were male (74.63%), aged 18–89 (average 50.62). Studies were mainly from high (82%) and medium (17%) Human Development Index (HDI) countries. Dietary surveys included a Food Frequency Questionnaire (FFQ) (58.8%), interviews/questionnaires (17.6%), and an FFQ with a photographic atlas (5.9%). Certain foods in excess like fruits, vegetables, and tea were inversely associated with OSCC, while salty meats, dairy, coffee, sausages, and fried and spicy foods were positively associated. Due to the heterogeneity of the tools used to obtain food frequency data, the results should be interpreted cautiously. New standardized studies and randomized trials are essential to advance understanding and control confounding factors in this field.