Dental implant and abutment in PEEK: stress assessment in single crown retainers on anterior region.

OBJECTIVE: Stress distribution assessment by finite elements analysis in poly(etheretherketone) (PEEK) implant and abutment as retainers of single crowns in the anterior region. MATERIALS AND METHODS: Five 3D models were created, varying implant/abutment manufacturing materials: titanium (Ti), zirconia (Zr), pure PEEK (PEEKp), carbon fiber-reinforced PEEK (PEEKc), glass fiber-reinforced PEEK (PEEKg). A 50 N load was applied 30o off-axis at the incisal edge of the upper central incisor. The Von Mises stress (σvM) was evaluated on abutment, implant/screw, and minimum principal stress (σmin) and maximum shear stress (τmax) for cortical and cancellous bone. RESULTS: The abutment σvM lowest stress was observed in PEEKp group, being 70% lower than Ti and 74% than Zr. On the implant, PEEKp reduced 68% compared to Ti and a 71% to Zr. In the abutment screws, an increase of at least 33% was found in PEEKc compared to Ti, and of at least 81% to Zr. For cortical bone, the highest τmax values were in the PEEKp group, and a slight increase in stress was observed compared to all PEEK groups with Ti and Zr. For σmin, the highest stress was found in the PEEKc. Stress increased at least 7% in cancellous bone for all PEEK groups. CONCLUSION: Abutments and implants made by PEEKc concentrate less σvM stress, transmitting greater stress to the cortical and medullary bone. CLINICAL RELEVANCE: The best stress distribution in PEEKc components may contribute to decreased stress shielding; in vitro and in vivo research is recommended to investigate this.

Effects of disinfection with a vinegar-hydrogen peroxide mixture on the surface characteristics of denture acrylic resins.

OBJECTIVE: This study aimed to investigate changes in the surface characteristics of two denture resins when disinfected with a vinegar-hydrogen peroxide (VHP) mixture. MATERIALS AND METHODS: Microwave-polymerized or 3D printed acrylic resin disks were immersed for 900 min (simulating 90 daily uses) in the following solutions (N = 10): water; 0.5% sodium hypochlorite; hydrogen peroxide and water dilution (1:1 ratio); vinegar and water dilution (1:1 ratio); and VHP mixture. Surface roughness, Knoop microhardness, surface free energy, and scanning electron microscopic images were assessed before and after the immersions. Results were compared using the 2-way ANOVA for repeated measures and Tukey test, at 5% significance. RESULTS: Surface roughness and microhardness did not differ (P > .05) among the solutions and times. Surface free energy and its dispersive component increased (P < .05) for all solutions. All solutions, except for water and VHP mixture, degraded microtopography. CONCLUSIONS: The VHP mixture was not deleterious to conventional and 3D-printed resin surfaces. CLINICAL RELEVANCE: Conventional and 3D printed resin dentures can be disinfected with a VHP mixture in a 1:1 ratio because this mixture does not substantially affect the surface characteristics after 90 daily immersions. On the contrary, sodium hypochlorite, hydrogen peroxide, and vinegar solutions, even in low concentrations, should be used with caution for denture disinfection because they may alter the resin microtopography over time.

Differential protein expression of osteoclastogenic factors in odontogenic cysts and tumors.

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.

Three names, one species: junior synonyms for the Atlantic Forest emerald dragonfly Navicordulia atlantica (Odonata: Corduliidae s.s.)

ABSTRACT Three Atlantic Forest endemic species of emerald dragonflies of the genus Navicordulia Machado & Costa, 1995 are reviewed through a morphological comparative analysis. All name-bearing types and additional specimens of the Navicordulia atlantica-complex—Navicordulia atlantica Machado & Costa, 1995, Navicordulia mielkei Machado & Costa, 1995 and Navicordulia miersi Machado & Costa, 1995—were investigated to assess their taxonomic and nomenclatural status. Based on our results the hypothesis of these three nomina corresponding to distinct species is no longer supported. The proportional size of caudal appendages, an additional crossvein in cubito-anal space in the hind wing, as well as minor differences in coloration of pterostigma are not reliable diagnostic characters for supporting their specific status. We consider the three simultaneously available nomina as synonyms, and by action of the first reviser, Navicordulia atlantica Machado & Costa, 1995 is selected as valid nomen, hence N. mielkei syn. nov. and N. miersi syn. nov. are their subjective junior synonyms. Photos, other illustrations, and a new species-level diagnosis are given. Despite of the advances of taxonomic knowledge of Navicordulia, the second species-rich corduliid genus in the Neotropical region, the status of some species still necessitates a full revision.

Differential protein expression of osteoclastogenic factors in odontogenic cysts and tumors

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.

A mobile application to guide healthcare professionals in the correct technique for personal protective equipment use during the COVID-19 pandemic

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. (AU)

Validation of algorithms for donning and doffing personal protective equipment during the COVID-19 pandemic

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. (AU)

A taxonomic synopsis of South American Cyanogomphini Carle with description of Cyanogomphus angelomachadoi sp. nov. from the Cerrado of Brazil (Odonata: Gomphidae).

A synopsis of Cyanogomphini Carle, 1986 (sensu Belle 1996), including all species currently under the genera Cyanogomphus Selys, 1873, and Tibiagomphus Belle, 1992, is provided. Cyanogomphus angelomachadoi sp. nov. (Holotype ♂ deposited in DZRJ: Brazil, Minas Gerais State, Jaboticatubas municipality, Parque Nacional da Serra do Cipó, collecting site "Córrego das Pedras" 19°22'17"S, 43°36'03"W, 766 m a.s.l., 12.XII.2011, A.P.M. Santos & D.M. Takiya leg.) is described and illustrated based on four males and two females from Minas Gerais and São Paulo States, southeastern Brazil. The new species is most similar to C. waltheri Selys, 1873, from which it can be distinguished by its smaller size; larger pale areas on mesepisternum; pale dorsal surface of metathoracic tibia; larger distal concavity on epiproct, with laterodistal projection, in lateral view forefinger-shaped; and occurrence in Cerrado province. Five species are recognized in Cyanogomphini, and for each one a synonymy, diagnoses, identification key and maps of distribution are presented. The status of sibling taxa Tibiagomphus uncatus (Fraser, 1947) and T. noval (Rodrigues Capítulo, 1985), as well as the Agriogomphus-complex of genera are also discussed.

When rare is just a matter of sampling: unexpected dominance of clubtail dragonflies (Odonata, Gomphidae) through different collecting methods at Parque Nacional da Serra do Cipó, Minas Gerais State, Brazil

When rare is just a matter of sampling: Unexpected dominance of clubtail dragonflies (Odonata, Gomphidae) through different collecting methods at Parque Nacional da Serra do Cipó, Minas Gerais State, Brazil. Capture of dragonfly adults during two short expeditions to Parque Nacional da Serra do Cipó, Minas Gerais State, using three distinct collecting methodsaerial nets, Malaise and light sheet trapsis reported. The results are outstanding due the high number of species of Gomphidae (7 out of 26 Odonata species), including a new species of Cyanogomphus Selys, 1873, obtained by two non-traditional collecting methods. Because active collecting with aerial nets is the standard approach for dragonfly inventories, we discuss some aspects of the use of traps, comparing our results with those in the literature, suggesting they should be used as complementary methods in faunistic studies. Furthermore, Zonophora campanulata annulata Belle, 1983 is recorded for the first time from Minas Gerais State and taxonomic notes about Phyllogomphoides regularis (Selys, 1873) and Progomphus complicatus Selys, 1854 are also given.

Esquizo-ocupação: uma ferramenta de análise da instituição Terapia Ocupacional / The Schizo-occupation: a tool for the analysis of the institution Occupational Therapy

O presente artigo propõe o conceito-exercício 'esquizo-ocupação' como uma ferramenta de análise para problematizar a instituição 'Terapia Ocupacional'. Inspirada na esquizoanálise e na análise de como a instituição 'terapia ocupacional' vem se constituindo enquanto um campo de saber, o conceito-exercício...