Diphosphonate immobilization on hydroxyapatite-coated titanium--method description.

Purpose: The aim of this study was to promote the immobilization of a bone activity biomodulator (diphosphonate) on titanium, commonly used in implant dentistry, to provide a local method of delivering this drug during the osseointegration process.

Methods: The implant material used in this study was commercially wrought titanium (Ticp), 99.9 mass%, grade II.

Evaluation of mechanical properties on three nanofilled composites.

The purpose of this study was to evaluate the mechanical behavior of three composites with nanoparticles Filtek Z350 XT (3M ESPE), Esthet X (Dentsply), Grandio (Voco) in enamel and body shades (A2) trough nanohardness, elastic modulus, compressive strength test, flexural strength test, diametral tensile strength, flexural modulus, weight filler content and Knoop microhardness. One sample of each material was submitted to nanohardness and elastic modulus. Five values of ten indentations were considered valids inside confidence intereval.

Evaluation of inorganic particles of composite resins with nanofiller content.

The purposes of this study were evaluate by energy dispersed X-ray (EDS) and scanning electron microscopy (SEM) the inorganic particles of three nanofilled composite resins, comparing particles sizes, shape and composition, and the filler weight content by thermogravimetric analyzes (TGA). Three composite resins classified as nanofilled were selected to this study: Esthet-X; Grandio; Filtek Supreme XT. The shade was standardized (A2) for enamel (E) or dentin (D).

Surface changes in denture soft liners with and without sealer coating following abrasion with mechanical brushing.

Aim: To evaluate the surface alterations of soft liners with or without sealer coating following abrasion with mechanical brushing.

Methods: Thirty specimens were made of a methacrylate- (Coe-Soft) and a siloxane-based material (Ufi-Gel SC), and 15 received two coatings of surface sealer. The specimens were submitted to a mechanical brushing-dentifrice assay under 200g of force at 250 cycles/min.

Evaluation of bond strength and internal adaptation between the dental cavity and adhesives applied in one and two layers.

This research evaluated the influence of the number of adhesive layers of three adhesive systems on microtensile bond strength (microTBS) to dentin and the internal adaptation between the dental structure and the resin composite restoration. Two cavities (C-factor = 3) were made on the buccal surfaces of 30 bovine incisors. Scotchbond Multi-Purpose (MP), Adper Single Bond 2 (SB) and Clearfil SE Bond (CSB) were applied in one layer (MP-I, SB-I and CSB-I) and in two layers (MP-II, SB-II and CSB-II).

Evaluation of tensile strength of different configurations of orthodontic retraction loops for obtaining optimized forces.

The aim of this study was to analyze the mechanical behavior of different orthodontic retraction loops. Two designs of orthodontic loops for closing space were analyzed: teardrop-shaped (T) and circle-shaped loop (C), of two different heights (6 and 8 mm), and two types of orthodontic wires (stainless steel - 0.19' x 0.

Cumulative effect of disinfection procedures on microhardness and tridimensional stability of a poly(methyl methacrylate) denture base resin.

Microwave irradiation has been used for disinfection of dentures instead of chemical solutions; yet, its effect on resin properties after repeated procedures still is unclear. This study evaluated the cumulative effect of two disinfection methods on Knoop microhardness and tridimensional stability of a poly(methyl methacrylate) denture base resin. For the microhardness measurement, 24-resin discs received mechanical polishing and were submitted to the following treatments: (1) control (no disinfection), (2) chemical disinfection (immersion in 100ppm chloride solution for 24h), or (3) microwave disinfection (irradiation at 690 W for 6 min).

Maximum occlusal force and medial mandibular flexure in relation to vertical facial pattern: a cross-sectional study.

Background: Vertical facial pattern may be related to the direction of pull of the masticatory muscles, yet its effect on occlusal force and elastic deformation of the mandible still is unclear. This study tested whether the variation in vertical facial pattern is related to the variation in maximum occlusal force (MOF) and medial mandibular flexure (MMF) in 51 fully-dentate adults.

Methods: Data from cephalometric analysis according to the method of Ricketts were used to divide the subjects into three groups: Dolichofacial (n = 6), Mesofacial (n = 10) and Brachyfacial (n = 35).

Shear bond strength of indirect resin to NiCr with different metal surface preparations.

This study sought to evaluate the shear bond strength of indirect resin to nickel chromium (NiCr) after different surface preparations. Sixty-four metal samples were divided into four groups, according to surface preparation, and two layers of opaque resin and three layers of body resin were applied. Each group was divided into two subgroups based on storage period in distilled water at 37 degrees C.

Surface modification of titanium with hydrothermal treatment at high pressure.

Surface modification of titanium was investigated by means of hydrothermal treatment with a maximum pressure of 6.3 MPa (280 degrees C temperature) in CaO solution or water to improve bioactivity and biocompatibility. As a result, calcium titanate was formed on the titanium surface.

Strengthening of calcium phosphate cement by compounding calcium carbonate whiskers.

The purpose of this study was to investigate how aragonite (calcium carbonate) whiskers influenced the strengthening and carbonating of alpha-tricalcium phosphate (alpha-TCP) based calcium phosphate cement. Aragonite whiskers of 0.95 microm width with an aspect ratio of 6.

Porous Ti-6Al-4V alloy fabricated by spark plasma sintering for biomimetic surface modification.

Porous compacts with both biological and biomechanical compatibilities and high strength were developed. Spherical powders of Ti-6Al-4V alloy, which were either as received or surface modified with the use of calcium ions by hydrothermal treatment (HTT), were fabricated by a spark plasma sintering process. The porous compacts of pure Ti were used as reference materials.

Evaluation of apatite ceramics containing alpha-tricalcium phosphate by immersion in simulated body fluid.

The purpose of this study was to estimate the availability of alpha-tricalcium phosphate (alpha-TCP) on/in hydroxyapatite (HAP) ceramics for bioactivity as bone-substitute materials by immersion in a simulated body fluid (SBF; Hanks' solution) containing ion concentrations similar to those in human blood plasma. Two alpha-TCP-surface-modified HAP and alpha-TCP-HAP composite materials were prepared by orthophosphoric acid treatment of sintered HAP and controlling the crystal phases of calcium phosphate cement, respectively. After immersion in SBF, the sintered HAP modified on the surface in an approximately 0.

Surface-layer modification of hydroxyapatite ceramic with acid and heat treatments.

The purpose of this study was to examine or characterize the surface layer of a calcium phosphate ceramic with a gradual compositional change from alpha-tricalcium phosphate (alpha-TCP) on the surface to hydroxyapatite (HAP) on the inside. The surface of a dense HAP ceramic was acid-treated for 1 hour with orthophosphoric acid (H3PO4) solutions of several concentrations (0.5, 1.