Abstract: The osteolytic activity of odontogenic cysts and tumors is directly associated with their growth and aggressiveness. The influence of proteins expressed by epithelial and mesenchymal cells on this biological event differs between indolent cystic lesions, aggressive cystic lesions, and odontogenic tumors. The objective of this study was to compare the immunohistochemical expression of factors that stimulate (receptor activator of nuclear factor kappa-Β ligand – RANKL, cathepsin K – CatK and matrix metallopeptidase 8 – MMP-8) and inhibit (osteoprotegerin – OPG) osteoclastogenesis between dentigerous cyst (DC), glandular odontogenic cyst (GOC), odontogenic keratocyst (OKC), and ameloblastoma (AB). Paraffin-embedded sections of nine DCs, nine GOCs, 20 OKCs, 21 ABs, and four dental follicles (DFs) were subjected to immunohistochemistry. Immunoreactivity was analyzed semiquantitatively and quantitatively in epithelium and connective tissue, respectively. The proteins were immunoexpressed in epithelial and mesenchymal cells of all lesions studied. The expression of RANKL and CatK was higher in OKC, AB, and GOC (p<0.005). Higher expression of OPG was found in DF and DC compared to the other markers (p<0.005). MMP-8 expression was high in GOC and OKC. This study demonstrated the differential expression of factors that inhibit and stimulate bone resorption during the development of DC, GOC, OKC, and AB. Higher expression of RANKL and CatK was observed in more aggressive lesions. OPG appears to be one of the molecules responsible for the slower growth of DC.

Abstract Introduction The prolonged or incorrect use of facial masks, respirators and glasses or visors results in friction, pressure and shear forces that constantly act on the facial skin, leading to lesions and dermatitis. Objective To develop and validate algorithms to guide health professionals in the correct use of personal protective equipment (PPE) and indicate preventive measures against skin injuries caused by inappropriate use during the COVID-19 pandemic. Methods For the develoment of the algorithms, an integrative literature review was performed using the following databases: PubMed, SciELO, and LILACS. The algorithms were evaluated by 59 health professionals (nurses, doctors, and physiotherapists), using the Delphi technique. A content validity index (CVI) was used for the statistical analysis. Results The experts classified the items of the algorithms from fully inadequate to fully adequate in the first round of consultations, and from partially adequate to fully adequate in the second round. The overall CVI values were of 0.83 and 1.0 in the first and second rounds respectively. Conclusion The algorithms validated by the expert panel can be used by health professionals when donning and doffing PPE, and to prevent the facial-skin lesions caused by their use.

Abstract Objectives The present study aimed to develop an application to guide healthcare professionals on using personal protective equipment (PPE) during the COVID-19 pandemic and prevent and treat skin lesions caused by these devices. Methods This is a study on technological production. The framework for application development consisted in the following phases: Phase 1-“Design: identification of application development requirements;” Phase 2-“Application prototype development”: including an integrative literature review in major databases; Phase 3-“Application construction”: elaboration of the decision tree, algorithm, database structuring, and software development; Phase 4-“Transition”: application functionality test. Result Our application Simplifica EPI is an innovative technology; this software is a tool to assist healthcare professionals in using PPE. In addition, it describes how to prevent and care for skin lesions caused by PPE. Simplifica EPI has 25 screens and 32 images. It will be available on the Google Play Store after its registration with the Brazilian National Institute of Industrial Property. Conclusions After an integrative literature review, the application Simplifica EPI was developed as an innovative technology with great potential for use by healthcare professionals.