New adhesive protocol improves shear bond strength of Polyetherketoneketone (PEKK).

OBJECTIVE: Inert surface of Polyetherketoneketone (PEKK) jeopardizes resin bonding. This study aimed to present a new adhesive protocol to improve PEKK bonding. METHODS: A total of 360 PEKK blocks were milled, polished (maximum roughness of 0.20 µm), and randomly assigned to groups. The new protocol was applied (n = 36) and compared to conventional treatments (no treatment; sandblasting (110-µm Al2O3 and silica); no adhesive; Visiolink (Bredent); and PEKKbond (AnaxDent)) (n = 36). For the new protocol, the surface was blasted (110 µm Al2O3 and 96% isopropyl alcohol at 60 psi), followed by 96% isopropyl alcohol washing, and air drying. PEKKbond was applied (dried for 3 min at 77 °C), followed by Visiolink (dried for 3 min at 60 °C); both light-cured for 3 min (800 mW/cm2). Preopaque (GC Europe) and Opaque (AnaxDent) were applied and light-cured (5 min). Morphological topography was analyzed, and flowable gingiva-colored composite (AnaxGum, AnaxDent) was bonded. All specimens were aged for 24 h and thermocycled (5000 cycles, 5-55 °C). Shear bond strength (SBS) was measured (MPa) and data were analyzed by two-way ANOVA, Tukey, and Weibull moduli estimation (α = 0.05). RESULTS: The highest SBS values were found in the new protocol (p < 0.05), regardless of aging. Thermocycling reduced SBS (p < 0.05), while Al2O3 and PEKKbond produced higher SBS values than silica and Visiolink, respectively (p < 0.05). SIGNIFICANCE: The new protocol strongly improves PEKK adhesiveness, and this can reflect in the longevity of prostheses.

Activation and installation of orthodontic appliances temporarily impairs mastication.

OBJECTIVES: To investigate the masticatory (masticatory performance, bite force, swallowing threshold, muscle activity, and questionnaires) and nutritional (nutrient intake) impacts of the activation and/or installation of different orthodontic appliances (fixed labial, lingual appliances, and clear aligners). MATERIALS AND METHODS: Six electronic databases and gray literature were searched (up to May 2021) for relevant studies evaluating mastication and nutrition after activation/installation of orthodontic appliances. This review followed PRISMA guidelines and was registered at PROSPERO (CRD42020199510). The risk of bias (RoB 2 and ROBINS-I) and evidence quality Grading of Recommendations Assessment, Development, and Evaluation were analyzed. RESULTS: Of 4226 recorded and screened, 15 studies were finally included. Masticatory performance (standardized mean difference [SMD]: 1.069; 95% coefficient interval [CI]: 0.619 to 1.518) and bite force (SMD: -2.542; 95% CI: -4.867 to -0.217) reduced in the first 24 to 48 hours of fixed labial appliance installation/activation, but they were both normalized after 30 days (P > .05). The swallowing threshold remained constant (P > .05). Nutritional intake was rarely reported but showed copper (P = .002) and manganese (P = .016) reductions, with higher calorie and fat intake (P < .05). Lingual appliances impacted chewing more than labial, and clear aligner wearers reported fewer chewing problems (P < .001). Low to very low levels of evidence were found. CONCLUSIONS: Based on low to very low levels of evidence, mastication was reduced during the first 24 to 48 hours of fixed labial appliance activation/installation, but it was transitory (up to 30 days). Due to insufficient data, the nutritional impact of orthodontic appliances was not conclusive.

Effects of noninvasive ventilation with bilevel positive airway pressure on exercise tolerance and dyspnea in heart failure patients.

BACKGROUND: Heart failure (HF) is a syndrome that results in inadequate blood supply, leading to a number of structural and functional changes. Noninvasive ventilatory support (NIVS) is used as an adjuvant treatment to improve the functional capacity of these patients. OBJECTIVE: To investigate the effect of NIVS with bilevel positive airway pressure ventilation (BiPAP) on exercise tolerance and dyspnea in HF patients. METHODS: Forty patients with New York Heart Association class I/II/III HF were randomly assigned either to a NIVS group (n = 20) or control group (n = 20). All patients underwent two 6-min walk tests (6MWT), with a 30-min interval between them. In the NIVS group, the patients performed the BiPAP with an inspiratory positive airway pressure of 12 cmH2O and expiratory positive airway pressure of 6 cmH2O for 30 min. At baseline, and after the first and second 6MWT, the heart rate, systolic and diastolic blood pressure, peripheral oxygen saturation (SaO2), and dyspnea were evaluated. RESULTS: Forty patients completed the study safely according to the randomization protocol, and no adverse events were reported during the tests. The NIVS group showed a significant improvement in the 6MWT distance (68.3 vs. 9.8 m) and dyspnea (1.3 vs. 3.1) compared with the control group. No serious adverse events were reported. CONCLUSIONS: NIVS/BiPAP showed beneficial effects on exercise tolerance and dyspnea. It was safe and well tolerated by HF patients and should be considered for inclusion in cardiac rehabilitation programs.

Growth of aluminum-free porous oxide layers on titanium and its alloys Ti-6Al-4V and Ti-6Al-7Nb by micro-arc oxidation.

The growth of oxides on the surfaces of pure Ti and two of its ternary alloys, Ti-6Al-4V and Ti-6Al-7Nb, by micro-arc oxidation (MAO) in a pH 5 phosphate buffer was investigated. The primary aim was to form thick, porous, and aluminum-free oxide layers, because these characteristics favor bonding between bone and metal when the latter is implanted in the human body. On Ti, Ti-6Al-4 V, and Ti-6Al-7Nb, the oxides exhibited breakdown potentials of about 200 V, 130 V, and 140 V, respectively, indicating that the oxide formed on the pure metal is the most stable. The use of the MAO procedure led to the formation of highly porous oxides, with a uniform distribution of pores; the pores varied in size, depending on the anodizing applied voltage and time. Irrespective of the material being anodized, Raman analyses allowed us to determine that the oxide films consisted mainly of the anatase phase of TiO2, and XPS results indicated that this oxide is free of Al and any other alloying element.

Preparation and characterization of biomimetically and electrochemically deposited hydroxyapatite coatings on micro-arc oxidized Ti-13Nb-13Zr.

Surface properties and corrosion resistance analyses of Ti-13Nb-13Zr coated by an oxide film (obtained by micro-arc oxidation at 300 V) or an oxide/hydroxyapatite (HA) film are reported. HA films were biomimetically or electrochemically deposited on the alloy/oxide surface, and their properties compared. Both the biomimetic and the electrochemical method yielded rough and globular apatite surfaces (10-20 µm globules for the former and 1-2 µm for the latter). As inferred from XRD data, the electrochemical method yielded more biologic-like HA films, while the biomimetic method yielded films containing a mixture of calcium phosphate phases. Coated Ti-13Nb-13Zr samples were immersed in an aerated PBS solution and continuously analyzed during 49 days. Considering that, after immersion, the biomimetically deposited films presented smaller variations in thickness and morphology and higher electric resistance (determined by electrochemical impedance spectroscopy), they clearly provide significantly better protection to the Ti-13Nb-13Zr alloy when in PBS solution.

Influence of hydroxyapatite on the corrosion resistance of the Ti-13Nb-13Zr alloy.

Electrochemical analyses on the biocompatible alloy Ti-13Nb-13Zr wt% in an electrolyte simulating physiological medium (PBS solution) are reported. Hydroxyapatite (HA) films were obtained on the alloy by electrodeposition at constant cathodic current. Samples of the alloy covered with an anodic-oxide film or an anodic-oxide/HA film were analyzed by open circuit potential and electrochemical impedance spectroscopy measurements during 180 days in the PBS electrolyte. Analyses of the open-circuit potential (E (oc)) values indicated that the oxide/HA film presents better protection characteristics than the oxide only. This behavior was corroborated by the higher film resistances obtained from impedance data, indicating that, besides improving the alloy osteointegration, the hydroxyapatite film may also increase the corrosion protection of the biomaterial.

Adesão ao rastreamento contra o câncer de mama no ESF Nossa Senhora das Graças, no município de Ipaba, MG

Este projeto intervencionista foi desenvolvido com base nos dados de saúde regionais da cidade de Ipaba, situada na região leste de Minas Gerais, em uma unidade de saúde denominada Nossa Senhora das Graças, com vistas a aumentar a adesão ao rastreamento de câncer de mama, controle das complicações e diminuição na taxa de mortalidade nos indivíduos do sexo feminino adscritos no PSF em questão. Este tipo de câncer é o que mais atinge as mulheres, todos os anos, possuindo uma taxa elevada de mortalidade no país devido ao diagnostico tardio. Seu prognostico tem relação com o tempo de instalação da doença, sendo necessário reduzir o tempo de diagnostico deste. Diante disto, foi elaborado um plano de intervenção para aumentar a adesão das mulheres adscritas pela Unidade de saúde aos exames preventivos do câncer de mama e auto exame regular. Observou-se a viabilidade do plano, assim como a necessidade de participação de toda a equipe de saúde na construção e aplicação deste para uma maior efetividade.