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.

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).

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.

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.

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).

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.