Immunocompromised patients and coronavirus disease 2019: a review and recommendations for dental health care

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

Anti-apoptotic gene transcription signature of salivary gland neoplasms

BACKGROUND: Development of accurate therapeutic approaches to salivary gland neoplasms depends on better understanding of their molecular pathogenesis. Tumour growth is regulated by the balance between proliferation and apoptosis. Few studies have investigated apoptosis in salivary tumours relying almost exclusively on immunohistochemistry or TUNEL assay. Furthermore, there is no information regarding the mRNA expression profile of apoptotic genes in salivary tumors. Our objective was to investigate the quantitative expression of BCL-2 (anti-apoptotic), BAX and Caspase3 (pro-apoptotic genes) mRNAs in salivary gland neoplasms and examine the association of these data with tumour size, proliferative activity and p53 staining (parameters associated with a poor prognosis of salivary tumours patients). METHODS: We investigated the apoptotic profile of salivary neoplasms in twenty fresh samples of benign and seven samples of malignant salivary neoplasms, using quantitative real time PCR. We further assessed p53 and ki-67 immunopositivity and obtained clinical tumour size data. RESULTS: We demonstrated that BCL-2 mRNA is overexpressed in salivary neoplasms, leading to an overall anti-apoptotic profile. We also found an association between the anti-apoptotic index (BCL-2/BAX) with p53 immunoexpression. A higher proliferative activity was found in the malignant tumours. In addition, tumour size was associated with cell proliferation but not with the transcription of apoptotic genes. CONCLUSION: In conclusion, we show an anti-apoptotic gene expression profile in salivary neoplasms in association with p53 staining, but independent of cell proliferation and tumour size

Age-Related Metabolic Pathways Changes in Dental Follicles: A Pilot Study

Aging is not a matter of choice; it is our fate. The “time-dependent functional decline that affects most living organisms” is coupled with several alterations in cellular processes, such as cell senescence, epigenetic alterations, genomic instability, stem cell exhaustion, among others. Age-related morphological changes in dental follicles have been investigated for decades, mainly motivated by the fact that cysts and tumors may arise in association with unerupted and/or impacted teeth. The more we understand the physiology of dental follicles, the more we are able to contextualize biological events that can be associated with the occurrence of odontogenic lesions, whose incidence increases with age. Thus, our objective was to assess age-related changes in metabolic pathways of dental follicles associated with unerupted/impacted mandibular third molars from young and adult individuals. For this purpose, a convenience sample of formalin-fixed paraffin-embedded (FFPE) dental follicles from young (<16 y.o., n = 13) and adult (>26 y.o., n = 7) individuals was selected. Samples were analyzed by high-performance liquid chromatography-mass spectrometry (HPLC-MS)-based untargeted metabolomics. Multivariate and univariate analyses were conducted, and the prediction of altered pathways was performed by mummichog and Gene Set Enrichment Analysis (GSEA) approaches. Dental follicles from young and older individuals showed differences in pathways related to C21-steroid hormone biosynthesis, bile acid biosynthesis, galactose metabolism, androgen and estrogen biosynthesis, starch and sucrose metabolism, and lipoate metabolism. We conclude that metabolic pathways differences related to aging were observed between dental follicles from young and adult individuals. Our findings support that similar to other human tissues, dental follicles associated with unerupted tooth show alterations at a metabolic level with aging, which can pave the way for further studies on oral pathology, oral biology, and physiology

A clinical case of peripheral ameloblastoma

ipheral ameloblastoma (PA) is a rare, benign, extraosseous odontogenic soft tissue tumour that is confined to the gingiva or alveolar mucosa. The PA presents the same histological characteristics of intraosseous ameloblastoma, although it is less aggressive than this classical subtype. We report a clinical case of PA of the alveolar mucosa in the right posterior maxilla, highlighting the importance of histological examination to the diagnosis

A clinical case of peripheral ameloblastoma

The peripheral ameloblastoma (PA) is a rare, benign, extraosseous odontogenic soft tissue tumour that is confined to the gingiva or alveolar mucosa. The PA presents the same histological characteristics of intraosseous ameloblastoma, although it is less aggressive than this classical subtype. We report a clinical case of PA of the alveolar mucosa in the right posterior maxilla, highlighting the importance of histological examination to the diagnosis