Evaluation of Bone Heating, Drill Deformation, and Drill Roughness After Implant Osteotomy: Guided Surgery and Classic Drilling Procedure

Purpose: This study evaluated and compared bone heating, drill deformation, and drill roughness after several implant osteotomies in the guided surgery technique and the classic drilling procedure. Materials and Methods: The tibias of 20 rabbits were used. The animals were divided into a guided surgery group (GG) and a control group (CG); subgroups were then designated (G0, G1, G2, G3, and G4, corresponding to drills used 0, 10, 20, 30 and 40 times, respectively). Each animal received 10 sequential osteotomies (5 in each tibia) with each technique. Thermal changes were quantified, drill roughness was measured, and the drills were subjected to scanning electron microscopy. Results: Bone temperature generated by drilling was significantly higher in the GG than in the CG. Drill deformation in the GG and CG increased with drill use, and in the CG a significant difference between GO and groups G3 and G4 was observed. In the GG, a significant difference between GO and all other groups was found. For GG versus CG, a significant difference was found in the 40th osteotomy. Drill roughness in both groups was progressive in accordance with increased use, but there was no statistically significant difference between subgroups or between GG and CG overall. Conclusion: During preparation of implant osteotomies, the guided surgery technique generated a higher bone temperature and deformed drills more than the classic drilling procedure. The increase in tissue temperature was directly proportional to the number of times drills were used, but neither technique generated critical necrosis-inducing temperatures. Drill deformation was directly proportional to the number of times the drills were used. The roughness of the drills was directly proportional to the number of reuses in both groups but tended to be higher in the GG group.

A Quality Assessment of Titanium Castings Produced in an Experimental Short-Heating-Cycle Investment

The aim of this study was to evaluate the quality of casting produced in an experimental short-term heating-cycle investment. Thus, reaction layer and castability of titanium casting using an experimental spinel-based investment (VR) with short heating cycle were compared with the commercial short-heating-cycle spinel-based investment Trinell (TR), the silica-phosphate-based investment Rematitan Plus ( RP), and the conventional spinel-based investment Rematitan Ultra (RU). VR has polymeric fibers added to inorganic particles. Reaction layer assessments were carried out using Vickers hardness and elemental analysis using dispersive X-ray microanalysis (EDX). Mesh patterns were used for castability test, and powder characterization was made by scanning electron microscopy (SEM). Hardness evaluation showed no difference among the investments between 100 and 200 mu m. The most important contaminant element for VR, TR, and RU was oxygen. Higher levels of mold filling were found for TR, VR, and RU compared with that obtained with RP. The quality of castings, characterized by means of the assessments of reaction layer and castability, made from the VR was similar to the commercial investments TR and RU but superior to the RP.

Home range and habitat selection by the tropical screech-owl in a Brazilian savanna

Coordenação de Aperfeiçoamento de Pessoal de Nível Superior (CAPES)

Home Cooking and Phenolics: Effect of Thermal Treatment and Addition of Extra Virgin Olive Oil on the Phenolic Profile of Tomato Sauces

Tomato products are a key component of the Mediterranean diet, which is strongly related to a reduced risk of cardiovascular events. The effect of cooking time (15, 30, 45, and 60 min) and the addition of extra virgin olive oil (5 and 10%) on the phenolic content of tomato sauces was monitored using liquid chromatography coupled to tandem mass spectrometry. Concentration of phenolics in the tomato sauces decreased during the cooking process, with the exception of caffeic acid and tyrosol. The main degradation observed was the oxidation of quercetin, since the hydroxy-function at the C-ring of this flavonoid is not blocked by a sugar moiety, unlike rutin. Higher levels of virgin olive oil in tomato sauce seemed to enhance the extraction of phenolic compounds from the tomato, leading to higher phenolic contents in the sauces. Thus, the food matrix containing the phenolic compounds plays a crucial role in determining their accessibility.

Heating value of eucalypt wood grown on SRC for energy production

Conselho Nacional de Desenvolvimento Científico e Tecnológico (CNPq)

Home ranges of Guiana dolphins (Sotalia guianensis) (Cetacea: Delphinidae) in the Cananeia estuary, Brazil

Fundação de Amparo à Pesquisa do Estado de São Paulo (FAPESP)

Estudo de caso do conforto térmico de dois modelos construtivos em madeira: wood frame e log home

O presente trabalho consiste em demonstrar valores referentes ao conforto ambiental de dois modelos construtivos, sendo o primeiro um edifício já executado e o outro em fase de implantação, ambos no Campus Experimental de Itapeva, aplicando alguns conceitos em habitação mais sustentáveis de madeira na região de Itapeva, estado de São Paulo, Brasil. A edificação construída sedia duas salas de aula a partir da tipologia construtiva wood frame, constituída basicamente de paredes autoportantes compostas de ossatura de madeira tratada de pinus.sp, chapas estruturais em OSB, manta de isolamento térmico/acústico e fechamento interno e externo, respectivamente em gesso e sidding (lambris de madeira). A habitação em fase de início de implantação foi idealizada a partir da tipologia construtiva log-home, e atenderá a necessidade de espaço físico para abrigar o Centro Acadêmico e a empresa-júnior “PROMAD”, ambos do curso de Engenharia Industrial Madeireira do Campus Experimental da UNESP/Itapeva. Esta construção foi elaborada a partir de técnicas de baixo impacto ambiental, levando em consideração os resultados de análise térmica obtidos na edificação anterior. Em ambos modelos construtivos foram empregados recursos renováveis abundantes na região, como a madeira de reflorestamento de Pinus e de Eucalipto. Foi acrescentado ainda ao segundo modelo a utilização de resíduos industriais lignocelulósicos, como rolete de laminação e outros materiais locais disponíveis. A metodologia básica empregada para a obtenção de dados sobre o conforto térmico em relação as edificações foi, para o primeiro caso, a coleta de dados de temperatura e umidade utilizando um termo-higrômetro, a sistematização e análise de dados reais obtidos no interior da edificação. No segundo caso, o dimensionamento do conforto térmico... (Resumo completo, clicar acesso eletrônico abaixo)

O impacto da utilização do Home Broker sobre o custo de transação no mercado financeiro, alocação de carteira e assimetria de informação

O Objeto de estudo dessa monografia é a introdução de uma ferramenta como o Home Broker no mercado acionário brasileiro, e como essa ferramenta impactou as aplicações dos investidores domésticos. A análise desse trabalho pretende avaliar o mercado sob a ótica de três características principais: custos de transação, alocação de carteira e assimetria de informação

Home care: uma análise

Pós-graduação em Direito - FCHS

Effect of home-bleaching gels modified by calcium and/or fluoride and the application of nano-hydroxyapatite paste on in vitro enamel erosion susceptibility

This in vitro study compared the effect of bleaching agents modified by the addition of calcium and/or fluoride and the application of a nano-hydroxyapatite paste after bleaching, on the susceptibility of enamel to erosion. Bovine enamel cylindrical samples (3 mm diameter) were assigned to six groups (n = 20 specimens/group) according to the bleaching agent: no bleaching (C-control), 7.5% hydrogen peroxide gel (HP), HP with 0.5% calcium gluconate (HP+Ca), HP with 0.2% sodium fluoride (HP+F), HP with calcium and fluoride (HP+Ca+F) and HP followed by the application of a nano-hydroxyapatite agent (HP+NanoP). The gels were applied on the enamel surface (1 h) followed by cyclic erosive challenges (Sprite Zero®-2 min), for 14 days. The paste was applied after bleaching for 5 min (HP+NanoP). The enamel surface alteration was measured by contact profilometry (µm) (after 7 and 14 days). C-control (mean ± SD: 2.29 ± 0.37 at 7 days/4.86 ± 0.72 at 14 days) showed significantly lower loss compared to the experimental groups. HP+Ca (3.34 ± 0.37/6.75 ± 1.09) and HP+F (4.49 ± 0.92/7.61 ± 0.90) presented significantly lower enamel loss than HP (4.18 ± 0.50/10.30 ± 1.58) only for 14 days and HP+Ca+F (4.92 ± 1.03/8.12 ± 1.52) showed values similar to the HP+F group. The HP+NanoP (5.51 ± 1.04/9.61 ± 1.21) resulted in enamel loss similar to the HP after 14 days. It was found that 7.5% hydrogen peroxide increased the susceptibility of enamel to erosion. The addition of calcium or fluoride to the bleaching gel reduced the erosion effect, while the nano-hydroxyapatite agent did not provide any protective effect.

25 kHz amorphous core transformer for induction heating applications

The analysis of the feasibility and economics of amorphous core power transformers for induction heating applications in the field 10-50 kHz is developped. The results obtained on a 25 kHz-150 kVA concentric winding trial unit are presented. © 1990.

Feasibility of solar heating systems composed of recyclable packaging for low-income rural communities

Solar heaters are an appropriate technology in tropical and sub-tropical climates to heat bath water by solar energy. Low-cost solar heaters meet the demand of low-income rural communities which currently do not have access to this technology. Current research analyzes the economic viability of solar heaters, built with recyclable materials, to reduce electric energy bill. A solar heating system was built consisting of recyclable materials in accordance with the manuals provided by the Secretariat of Environment of the state of Paraná (SEMA). Duration of use of electric showers by families of rural properties was determined to calculate expenses and billing of electricity. Simulation and material costs showed that the system was feasible. Commercial solar heaters could be replaced at a cost of R$ 22.61 per month during 13 months.