Effect of thermal treatment on the morphology of PLZT thin films prepared from polymeric precursor method

Lead lanthanum zirconate titanate (PLZT) thin films with (9/65/35) stoichiometry were prepared by dip coating from polymeric precursor method. The films deposited on silicon (100) substrates, were thermally treated from 450° to 700°C for 6 hours in order to study the influence of thermal treatment on the crystallinity, microstructure, grain size and roughness of the final film. X-ray diffraction results showed that PLZT phase crystallizes at low temperature (500°C) and present preferential orientation. It was observed by scanning electron microscopy (SEM) that it is possible to obtain dense thin films at temperatures around 650°C. The atomic force microscopy (AFM) studies showed that the grain size and roughness are strongly influenced by the annealing temperature.

Effect of a heat-treatment on the linear dimensional change of a hard chairside reline resin

Statement of problem. Little data are available regarding the effect of heat-treatments on the dimensional stability of hard chairside reline resins. Purpose. The objective of this in vitro study was to evaluate whether a heat-treatment improves the dimensional stability of the reline resin Duraliner II and to compare the linear dimensional changes of this material with the heat-polymerized acrylic resin Lucitone 550. Material and methods. The materials were mixed according to the manufacturer's instructions and packed into a stainless steel split mold (50.0 mm diameter and 0.5 mm thickness) with reference points (A, B, C, and D). Duraliner II specimens were polymerized for 12 minutes in water at 37°C and bench cooled to room temperature before being removed from the mold. Twelve specimens were made and divided into 2 groups: group 1 specimens (n=6) were left untreated, and group 2 specimens (n=6) were submitted to a heat-treatment in a water bath at 55°C for 10 minutes and then bench cooled to room temperature. The 6 Lucitone specimens (control group) were polymerized in a water bath for 9 hours at 71°C. The specimens were removed after the mold reached the room temperature. A Nikon optical comparator was used to measure the distances between the reference points (AB and CD) on the stainless steel mold (baseline readings) and on the specimens to the nearest 0.001 mm. Measurements were made after processing and after the specimens had been stored in distilled water at 37°C for 8 different periods of time. Data were subjected to analysis of variance with repeated measures, followed by Tukey's multiple comparison test (P<.05). Results. All specimens exhibited shrinkage after processing (control, -0.41%; group 1, -0.26%; and group 2, -0.51%). Group 1 specimens showed greater shrinkage (-1.23%) than the control (-0.23%) and group 2 (-0.81%) specimens after 60 days of storage in water (P<.05). Conclusion. Within the limitations of this study, a significant improvement of the long-term dimensional stability of the Duraliner II reline resin was observed when the specimens were heat-treated. However, the shrinkage remained considerably higher than the denture base resin Lucitone 550. Copyright © 2002 by The Editorial Council of The Journal of Prosthetic Dentistry.

Effect of the Clinical Application of the GaA1As Laser in the Treatment of Dentine Hypersensitivity

Objective: The aim of this study was to evaluate the effectiveness of the clinical use of the gallium-aluminum-arsenium (GaAlAs) laser at the maximum and minimum energies recommended by the manufacturer for the treatment of dentine hypersensitivity. Background Data: Dentine hypersensitivity (DH) is a response to a stimulus that would not usually cause pain in a healthy tooth. It is characterized by sharp pain of short duration from the denuded dentin. Its etiology is unknown. The dentin only begins to show sensitivity when exposed to the buccal environment. This exposure can result after removal of the enamel and/or dental cement, or after root denudation. Different treatments are proposed for this disorder. Materials and Methods: In this study, 25 patients, with a total number of 106 cases of DH, were treated with GaAlAs low-level laser therapy (LLLT). 65% of the teeth were premolars; 14% were incisors and molars; 6.6% were canines. The teeth were irradiated with 3 and 5 J/cm 2 for up to six sessions, with an interval of 72 h between each application, and they were evaluated initially, after each application, and at 15 and 60 days follow-up post-treatment. Results: The treatment was effective in 86.53% and 88.88% of the irradiated teeth, respectively, with the minimum and maximum energy recommended by the manufacturer. There was a statistically significant difference between DH and after a follow-up of 60 days for both groups. The difference among the energy maximum and minimum was not significant. Conclusion: The GaAlAs low-level laser was effective in reducing initial DH. A significant difference was found between initial values of hypersensitivity and after 60 days follow-up post-treatment. No significant difference was found between minimum (3 J/cm 2) and maximum (5 J/cm 2) applied energy.

Effect of ceramic surface treatment on the microtensile bond strength between a resin cement and an alumina-based ceramic

Purpose: The objective of this study was to test the following hypothesis: the silica coating on ceramic surface increases the bond strength of resin cement to a ceramic. Materials and Methods: In-Ceram Alumina blocks were made and the ceramic surface was treated: G1 - sandblasting with 110-μm aluminum oxide particles; G2 - Rocatec System: tribochemicai silica coating (Rocatec-Pre powder + Rocatec-Plus powder + Rocatec-Sil); G3 - CoJet System: silica coating (CoJet-Sand) + ESPE-Sil. The ceramic blocks were cemented to composite blocks with Panavia F resin cement (under a load of 750 g/1 min). The cemented blocks were stored in distilled water at 37°C for 7 days and sectioned along the x and y axes with a diamond disk. Samples with an adhesive area of ca 0.8 mm 2 (n = 45) were obtained. The samples were attached to an adapted device for the microtensile test, which was performed in a universal testing machine (EMIC) at a crosshead speed of 1 mm/min. Results: The obtained results were submitted to ANOVA and Tukey's test. Mean values of tensile strength (MPa) and standard deviation values were: (G1) 16.8 ± 3.2; (G2) 30.6 ± 4.5; (G3) 33.0 ± 5.0. G2 and 63 presented greater tensile strength than G1. There was no significant difference between G2 and G3. All the failures took place at the ceramic/resin cement interface. Conclusion: The silica coating (Rocatec or CoJet systems) of the ceramic surface increased the bond strength between the Panavia F resin cement and alumina-based ceramic.

Effect of thermal treatment under oxygen atmosphere on the superconducting properties of RuSr2GdCu2O8

The discovery of the spatial uniform coexistence of superconductivity and ferromagnetism in rutheno-cuprates, RuSr2GdCu2O8 (Ru-1212), has spurred an extraordinary development in the study of the competition between magnetism and superconductivity. However, several points of their preparation process and characterization that determine their superconductive behavior are still obscure. The improvement of sample preparation conditions involves some thermal treatments in inert atmosphere. The first treatment results in the immediate formation of Sr2GdRuO 6. Using the CuO composition as a precursor, we produced Ru-1212. To turn it metallic and superconductor, besides the previous treatment, a final sinterization is carried out in oxygen flow for several days. Three Ru-1212 samples were produced by varying the last sinterization time (two, four, and six days under oxygen flow). Through measurements of x-ray diffraction, scanning electron microscopy, differential thermal analysis, magnetic susceptibility and mechanical spectroscopy, it was studied the influence of the treatments under oxygen atmosphere on the structural and superconducting properties of the material.

Effect of milk treatment on acidification, physicochemical characteristics, and probiotic cell counts in low fat yogurt

The effect of milk treatment (heat, high hydrostatic pressure - HHP, or combined heat and HHP) on acidification, physicochemical characteristics, and probiotic cell counts in low fat yogurt was studied. All samples were analyzed for fermentation time, pH, titratable acidity, total solids, water-holding capacity, syneresis, Hunter L*, a*, and b* values, Streptococcus thermophilus, Lactobacillus delbrueckii ssp bulgaricus, L. acidophilus, and Bifidobacterium longum. The application of HHP combined with thermal treatment resulted in yogurt gels with attractive physicochemical characteristics and high water-holding capacity. In addition to this, the milk treatment did not affect the probiotic bacteria growth. The balance of strains in the starter culture and level of inoculation influenced the yogurt fermentation and properties. The use of combined heat and HHP to treat milk before yogurt fermentation could be an alternative process for obtaining high quality, additive-free healthy products.

Effect of periodontal treatment on the incidence of preterm delivery: a systematic review.

Preterm birth is a major problem in public health in developed and developing countries and the search for risk factors of this event is important. The aim of this study was to review the effect of periodontal treatment on the incidence of preterm delivery. A wide research was executed considering an evaluation period between November of 1998 and October of 2009 at MEDLINE/PUBMED databases. The selection strategy consisted of the search for the following key-words: periodontal therapy or periodontal disease and pregnancy outcome or preterm birth. The search was limited for articles written in English. The randomized clinical trials that evaluated the effect of the non-surgical periodontal treatment on the incidence of Preterm Low Birth Weight (PLBW) were selected. In a total of 7 papers selected, the incidence of PLBW was lower in groups of women who were submitted to periodontal treatment. Reductions of Preterm Birth (PTB) ranged from 0.8% to 28.01%, while reduction of Low Birth Weight (LBW) ranged from 0.44% to 33%. In studies that analyzed these two variables together, there was variation between 4.57% to 71.5% in rates reduction. Due to heterogeneity of the data, the meta-analysis was not applied. The majority of the studies concluded that non-surgical periodontal treatment in pregnant women reduces incidence of preterm babies with low weight.

Effect of zoledronic acid used in the root surface treatment of late replanted teeth: A study in rats

This study evaluated the use of zoledronic acid, a resorption inhibitor, as a medication for root resorption treatment of late replanted teeth. Twenty-four maxillary right central incisors of rats were avulsed and kept dry for 30 min. Then, the teeth were divided into 2 groups. In group I, root surface was treated with 2% sodium fluoride for 20 min; in group II, 10-6M zoledronic acid solution was used for 20 min. All root canals were filled with calcium hydroxide. Next, teeth were replanted in their respective sockets. After 15 and 60 days post-replantation, the animals were killed and the anatomic pieces were obtained and prepared for microscopic and morphometric analyses. The results showed that zoledronic acid was capable of limiting the occurrence of root resorption and preserving cementum resorption. Further research must be performed to confirm the use of zoledronic acid in root surface treatment of late replanted teeth.

Effect of occlusal splint treatment on the temperature of different muscles in patients with TMD

Purpose: The aim of this study was to evaluate the effect of occlusal splint treatment on the temperature of masseter (inferior, intermediate and superior), anterior temporal, digastric and trapezius muscles in patients with temporomandibular disorder (TMD). Materials and methods: Thirty patients (6 male and 24 female) aged from 16 to 57 years (mean 37.8. ± 11.4 years) were selected. The patients were diagnosed with muscular TMD by clinical examination (application of Research Diagnostic Criteria questionnaire and physical examination). Occlusal splints in acrylic resin were inserted in all patients with a weekly follow-up. The superficial thermography (°C) on the both sides of the muscles was performed using a digital thermometer in a controlled temperature room. This procedure was performed before occlusal splint insertion (patient with pain) and after the completion of the treatment (patient without pain). The data were analyzed by 2-way repeated-measures ANOVA and means were compared by Tukey HSD test (P< .05). Results: After occlusal splint treatment a significant increase in temperature was observed in each muscle, both in the right and left sides. When the muscles were compared in the same period (before or after therapy) there was no significant difference among them. Conclusion: It can be concluded that the use of occlusal splint promoted a significant increase on the muscles temperature. There was symmetry in the temperature of muscles on the right and left sides both before and after the treatment. © 2010 Japan Prosthodontic Society.

Effect of ceramic surface treatment on the shear bond strength of a resin cement to different ceramic systems

This study evaluated three surface treatments and their effects on the shear bond strength between a resin cement and one of three ceramics. The ceramic surfaces were evaluated with scanning electron microscopy (SEM ) as well. Specimens were treated with 50 μm aluminum oxide airborne particles, 10% hydrofluoric acid etching, or a combination of the two. Using a matrix with a center hole (5.0 mm × 3.0 mm), the ceramic bonding areas were filled with resin cement following treatment. The specimens were submitted to thermal cycling (1,000 cycles) and the shear bond strength was tested (0.5 mm/minute). The failure mode and the effect of surface treatment were analyzed under SEM . Data were submitted to ANOVA and a Tukey test (α = 0.05). Duceram Plus and IPS Empress 2 composite specimens produced similar shear bond strength results (p > 0.05), regardless of the treatment method used. Hydrofluoric acid decreased the shear bond strength of In-Ceram Alumina specimens. For all materials, surface treatments changed the morphological surface. All treatments influenced the shear bond strength and failure mode of the ceramic/resin cement composites.

Effect of a hyperbolide mastication apparatus for the treatment of severe sleep bruxism in a child with cerebral palsy: Long-term follow-up

Purpose: Sleep bruxism is common among the various oromotor alterations found in individuals with cerebral palsy (CP). Few studies have investigated the use of the mastication device denominated hyperbola (HB) and none was found describing the use of such a device for the treatment of bruxism in children with CP. The aim of the present study was to evaluate the effect of the HB on electromyographic (EMG) activity in the jaw-closing muscles and the reduction in sleep bruxism in a child with CP using surface EMG analysis before and after nine months of treatment. Methods: A seven-year-old boy with severe spastic CP and sleep bruxism was enrolled in this study. The HB was chosen as the treatment option for sleep bruxism in this case because the child did not accept an occlusal splint. The HB has a hyperbolic shape and is made of soft, non-toxic, odorless, tasteless silicone. There are five different sizes of HB manufactured based on the diversity of tooth sizes. This device produces proprioceptive excitation in the dentoalveolar nerve, spindles and Golgi tendon organs. HB has been employed for the treatment of temporomandibular disorder, abnormal oro-dental development, abnormal occlusion, xerostomy, halitosis and bruxism. HB therapy was performed for 5 min six times a day over a nine-week period. Surface EMG of the mandible at rest and during maximum contraction was performed on the masseter and temporalis muscles bilaterally to evaluate electromyographic activity before and after nine months of HB usage. Results: HB usage led to a visible tendency toward the reorganization of mastication dynamics, achieving a marked balance in electromyographic activity of the jaw-closing muscles and improving the child's quality of life. Conclusion: Based on the findings of the present study, this noninvasive therapy may be useful for individuals with cerebral palsy due to its positive effects and low cost, which allows its use in the public health realm. Further clinical studies with a larger sample size are needed to validate these results and allow the development of a new treatment protocol for patients with spastic cerebral palsy. © 2013 Elsevier Ltd. All rights reserved.

Effect of the treatment of root surface-adhered necrotic periodontal ligament with propolis or fluoride in delayed rat tooth replantation

Objectives: The purpose of this study was to evaluate the application of 15 % propolis and 2 % acidulated-phosphate sodium fluoride solutions on the root surface-adhered necrotic cemental periodontal ligament in delayed tooth replantation. Materials and methods: Thirty Wistar rats (Rattus norvegicus, albinus) had their right upper incisor extracted and maintained in dry storage for 60 min. After this period, the dental papilla, enamel organ, and pulp tissue were removed, and the animals were randomly assigned to three groups: group I = immersion in saline for 10 min; group II = immersion in a 2 % acidulated-phosphate sodium fluoride solution for 10 min; and group III = immersion in a 15 % propolis and propylene glycol solution for 10 min. The root canals were filled with a calcium hydroxide paste and the teeth were replanted. Results: Inflammatory resorption, replacement resorption, and ankylosis were observed in all groups without a statistically significant difference (p > 0.05) among them. Conclusions: Under the tested conditions, the application of fluoride or propolis on root surface-adhered necrotic periodontal ligament did not favor the healing process in delayed tooth replantation. © 2013 Springer-Verlag Berlin Heidelberg.

Effect of treatment with l-amino oxidase fractions, from Bothrops jararaca venom on Ehrlich ascites tumor growth

Coordenação de Aperfeiçoamento de Pessoal de Nível Superior (CAPES)

Effect of ambulatory versus hospital treatment for gestational diabetes or hyperglycemia on infant mortality rates: a systematic review

CONTEXTO E OBJETIVO:Gestações complicadas pelo diabetes estão associadas com aumento das complicações neonatais e maternas. A complicação mais grave materna é o risco de desenvolver diabetes tipo 2 após 10-12 anos do parto. Para o controle rigoroso da glicose no sangue, as mulheres grávidas são tratadas de forma ambulatorial ou com internações hospitalares. O objetivo deste estudo é avaliar a efetividade do tratamento ambulatorial versus hospitalização em gestações complicadas por diabetes ou hiperglicemia.TIPO DE ESTUDO E LOCAL:Revisão sistemática conduzida em hospital universitário público.MÉTODOS:Uma revisão sistemática da literatura foi realizada e as principais bases de dados eletrônicas foram pesquisadas. A data da pesquisa mais recente foi 4 de setembro de 2011. Dois autores selecionaram independentemente os ensaios clínicos relevantes, avaliaram a qualidade metodológica e extraíram os dados.RESULTADOS:Apenas três estudos foram selecionados, com tamanho de amostra pequeno. Não houve diferença estatisticamente significativa entre o tratamento ambulatorial versus hospitalização em relação à mortalidade em nenhuma das subcategorias analisadas: mortes perinatais e neonatais, (risco relativo [RR] 0,65; 95% de intervalo de confiança [IC] 0,11-3,84, P = 0,63); morte neonatal (RR 0,29, IC 95% 0,01-6,07, P = 0,43), e óbitos infantis (RR 0,29, IC 95% 0,01-6,07, P = 0,43).CONCLUSÕES:Com base em estudos com risco de viés alto ou moderado, esta revisão demonstrou que não há diferença estatisticamente significante entre o tratamento ambulatorial comparado com o hospitalar na redução das taxas de mortalidade em gestações complicadas por diabetes ou hiperglicemia. Esta revisão sistemática também sugere a necessidade de mais ensaios clínicos randomizados sobre o assunto.

Effect of steam thermal treatment on the drying process of Eucalyptus dunnii variables

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