49 research outputs found
Subcutaneous tissue reaction to castor oil bean and calcium hydroxide in rats
Castor oil bean cement (COB) is a new material that has been used as an endodontic sealer, and is a candidate material for direct pulp capping. OBJECTIVE: The purpose of this study was to evaluate the biocompatibility of a new formulation of COB compared to calcium hydroxide cement (CH) and a control group without any material, in the subcutaneous tissue of rats. MATERIAL AND METHODS: The materials were prepared, packed into polyethylene tubes, and implanted in the rat dorsal subcutaneous tissue. Animals were sacrificed at the 7th and 50th days after implantation. A quantitative analysis of inflammatory cells was performed and data were subjected to ANOVA and Tukey's tests at 5% significance level. RESULTS: Comparing the mean number of inflammatory cells between the two experimental groups (COB and CH) and the control group, statistically significant difference (p=0.0001) was observed at 7 and 50 days. There were no significant differences (p=0.111) between tissue reaction to CH (382 inflammatory cells) and COB (330 inflammatory cells) after 7 days. After 50 days, significantly more inflammatory cells (p=0.02) were observed in the CH group (404 inflammatory cells) than in the COB group (177 inflammatory cells). CONCLUSIONS: These results demonstrate that the COB cement induces less inflammatory response within long periods
Effectiveness of carbamide peroxide and sodium perborate in non-vital discolored teeth
OBJECTIVE: To evaluate the efficacy of 16% carbamide peroxide gel (CP16%), tetrahydrate sodium perborate (SP) and mixture (CP16% + SP), in walking bleaching of non-vital discolored teeth. MATERIALS AND METHODS: Sixty single-rooted human premolars with intact crowns were used and initial color was assessed using Vita shade guide and standardized photos. The teeth were stained using rabbit fresh blood for 18 days and photos of discolored teeth and color evaluation were performed. The teeth were divided into 4 groups (n= 15), according to bleaching agent used: G1) CP16% gel; G2) CP16% gel + SP; G3) SP + distilled water; G4: control. The bleaching agents were replaced twice at 7-day intervals for 21 days. All teeth were evaluated by two endodontists at days 0, 7, 14 and 21 and the color changes were assessed using Vita shade guide and standardized photos. The results were analyzed by Kruskal-Wallis and Dunn's tests (p=0.05). RESULTS: The experimental groups presented statistically similar bleaching results (p>;0.05) at the end of 7, 14 and 21 days. These groups presented significantly higher bleaching efficacy than control group (G4) (
Avaliação do pH das soluções de hipoclorito de sódio 1% e 2,5% e digluconato de clorexidina 2% em função do tempo
This study compared the pH values among 2% chlorexidine gluconate solution manipulated, and 1% and 2,5% sodium hypochlorite solution manipulated and commercial in different periods of time. Different concentrations and presentations were used (commercial or manipulated) of sodium hypochlorite and chlorexidine gluconate solutions. The pH of samples was measured by digital pHmetro submerging the electrode in 2ml of solution in intervals of 0, 1, 7, 14 and 30 days after opening of the flasks of solutions. The results were submitted to dispersion test (Minitab 1.4 version) and it was verified that commercial mark Carrefour presented higher pH values in relation to other solutions and that 2% chlorexidine (Byoformula) it showed small pH values in relation to all of tested solutions.. It concluded that: endodontic irrigants presented pH stability for 30 days and 2% chlorexidine solution showed the smallest pH values.Este trabalho teve como objetivo comparar os valores de pH entre a solução de digluconato de clorexidina 2% manipulada, e o hipoclorito de sódio 1% e 2,5% manipulado e comercial em diferentes períodos de tempo. Foram utilizadas diferentes concentrações e apresentações (comerciais ou manipuladas) das soluções de hipoclorito de sódio e clorexidina. O pH das amostras foi aferido com um pHmetro digital submergindo o eletrodo em 2ml de cada solução em intervalos de 0, 1, 7, 14 e 30 dias após a abertura dos frascos das soluções. Os resultados foram submetidos ao teste de dispersão (Minitab versão 14) e verificou-se que a marca comercial Carrefour apresentou maiores valores de pH em relação às demais soluções e que a Clorexidina 2% (Byoformula) mostrou valores inferiores de pH em relação a todas as soluções testadas.. Conclui-se que as soluções irrigadoras testadas apresentaram estabilidade de pH durante 30 dias e a solução de clorexidina 2% mostrou os menores valores de pH
Preparation, Characterization and Biological Studies of B-TCP and B-TCP/Al2O3 Scaffolds Obtained by Gel-Casting of Foams
Replacement tissues for tissue engineering can be produced by seeding human cells onto scaffolds. In order to guarantee adequate bio-compatibility, porosity and mechanical resistance for promoting cellular growth, proliferation and differentiation within scaffold structures, it is necessary to investigate and improve materials and processing routes. beta-tricalcium phosphate can be considered a very suitable bio-ceramic material for bone therapy because of its biocompatibility, osteo-conductivity and neo-vascularization potential. Alumina is commonly used as a sintering additive. In this study, beta-TCP and beta-TCP/Al2O3 scaffolds were obtained by gel-casting method. The scaffolds showed high porosity (8688%) and pore sizes ranging from 200 to 500 mu m. Even though alumina did not promote improvement in beta-TCP/Al2O3 scaffolds in terms of mechanical performance, they showed great cytocompatibility as there was no cytotoxic and genotoxic effect. Therefore, beta-TCP and beta-TCP/Al2O3 scaffolds are good candidates for application in tissue engineering.Sao Paulo Research Foundation - FAPESPNational Council for Scientific and Technological DevelopmentNational Council for Scientific and Technological DevelopmentUniv Fed Sao Paulo UNIFESP, Sci & Technol Inst ICT, Bioceram Lab BIOCERAM, 330 Talim St, BR-12231280 Sao Jose Dos Campos, SP, BrazilCNPEM, Brazilian Nanotechnol Natl Lab LNNANO, POB 6192, BR-13083970 Campinas, SP, BrazilUniv Estadual Paulista Julio de Mesquita Filho UN, Sch Dent, Dept Biosci & Oral Diag, 777 Engenheiro Francisco Jose Longo Ave, BR-12245000 Sao Jose Dos Campos, SP, BrazilUniv Fed Sao Paulo UNIFESP, Sci & Technol Inst ICT, Bioceram Lab BIOCERAM, 330 Talim St, BR-12231280 Sao Jose Dos Campos, SP, BrazilFAPESP: 2010/00863-0National Council for Scientific and Technological Development: 456461/2014-0]CNPq/PIBITI/UNIFESPWeb of Scienc
Efficacy and safety of blood transfusion in obstetric patients: systematic review of the literature
Objectives: To evaluate the efficacy of blood transfusion compared to no intervention in obstetric patients. Material and methods: A systematic review was performed with Cochrane Database of Clinical Trials, PubMed, EMBASE and LILACS databases searched as of September, 2016. Two authors independently selected relevant clinical trials, assessed their methodological quality and extracted data, using the GRADE approach.
Results: Five studies within a total of 6,297 met the inclusion criteria, with women generally aged 20–40 years. Three included studies allocated women to receive blood transfusion or no intervention. Two other studies allocated women with either restricted or full blood supplies. The major issue regarding risk of bias was the extent of concealment of randomization and blinding. There was no statistically significant difference between blood transfusion versus no transfusion or restricted blood supply on mortality (relative risk 0.82 [95% confidential interval 0.32 to 2.09], p = 0.68; two studies; I2 = not applicable). Conclusions: Very low-quality evidence suggests no significant difference between blood transfusion and no intervention in obstetric patients, underlining the need for more robust clinical trials evaluating this area
Influence of prior 810-nm-diode intracanal laser irradiation on hydrophilic resin-based sealer obturation
Dentin wall structural changes caused by 810-nm-diode laser irradiation can influence the sealing ability of endodontic sealers. The objective of this study was to evaluate the apical leakage of AH Plus and RealSeal resin-based sealers with and without prior diode laser irradiation. Fifty-two single-rooted mandibular premolars were prepared and divided into 4 groups, according to the endodontic sealer used and the use or non-use of laser irradiation. The protocol for laser irradiation was 2.5W, continuous wave in scanning mode, with 4 exposures per tooth. After sample preparation, apical leakage of 50% ammoniacal silver nitrate impregnation was analyzed. When the teeth were not exposed to irradiation, the Real Seal sealer achieved the highest scores, showing the least leakage, with significant differences at the 5% level (Kruskal-Wallis test, p = 0.0004), compared with AH Plus. When the teeth were exposed to the 810-nm-diode laser irradiation, the sealing ability of AH Plus sealer was improved (p = 0282). In the Real Seal groups, the intracanal laser irradiation did not interfere with the leakage index, showing similar results in the GRS and GRSd groups (p = 0.1009)
Subcutaneous tissue reaction to castor oil bean and calcium hydroxide in rats
Castor oil bean cement (COB) is a new material that has been used as an endodontic sealer, and is a candidate material for direct pulp capping. OBJECTIVE: The purpose of this study was to evaluate the biocompatibility of a new formulation of COB compared to calcium hydroxide cement (CH) and a control group without any material, in the subcutaneous tissue of rats. MATERIAL AND METHODS: The materials were prepared, packed into polyethylene tubes, and implanted in the rat dorsal subcutaneous tissue. Animals were sacrificed at the 7th and 50th days after implantation. A quantitative analysis of inflammatory cells was performed and data were subjected to ANOVA and Tukey's tests at 5% significance level. RESULTS: Comparing the mean number of inflammatory cells between the two experimental groups (COB and CH) and the control group, statistically significant difference (p=0.0001) was observed at 7 and 50 days. There were no significant differences (p=0.111) between tissue reaction to CH (382 inflammatory cells) and COB (330 inflammatory cells) after 7 days. After 50 days, significantly more inflammatory cells (p=0.02) were observed in the CH group (404 inflammatory cells) than in the COB group (177 inflammatory cells). CONCLUSIONS: These results demonstrate that the COB cement induces less inflammatory response within long periods
Novel Coatings to Minimize Corrosion of Titanium in Oral Biofilm
The aim of this work is to investigate the effects produced by polymicrobial biofilm (Porphyromonas gingivalis, Streptococcus mutans, Streptococcus sanguinis, and Streptococcus salivarius) on the corrosion behavior of titanium dental implants. Pure titanium disks were polished and coated with titanium nitride (TiN) and silicon carbide (SiC) along with their quarternized versions. Next, the disks were cultivated in culture medium (BHI) with P. gingivalis, S. mutans, S. sanguinis, and S. salivarius and incubated anaerobically at 37 °C for 30 days. Titanium corrosion was evaluated through surface observation using Scanning Electron Microscope (SEM) and Atomic Force Microscopy (AFM). Furthermore, the Ti release in the medium was evaluated by Inductively Coupled Plasma Mass Spectrometry (ICP-MS). SEM images showed that coated Ti disks exhibited lower corrosion compared to non-coated disks, except for the quartenized TiN. This was confirmed by AFM, where the roughness was higher in non-coated Ti disks. ICP showed that Ti levels were low in all coating disks. These results indicate that these SiC and TiN-based coatings could be a useful tool to reduce surface corrosion on titanium implant surfaces
Penetração de peróxido de hidrogênio 38% no interior da câmara pulpar de dentes bovinos e humanos com ou sem restauração submetidos ao clareamento externo
Acredita-se que a penetração de peróxido de hidrogênio através do esmalte e dentina pode causar danos à polpa. A proposta deste trabalho foi avaliar a quantidade de peróxido de hidrogênio no interior da câmara pulpar de dentes bovinos e humanos com ou sem restauração, após clareamento pela técnica de consultório. Os dentes foram seccionados 3mm à junção amelo-cementária e divididos em dois grupos: A (setenta terceiros molares humanos) e B (setenta incisivos laterais bovinos) que foram subdivididos em: A1 e B1 restaurados com resina composta (Esthetic-X, Dentsply), A2 e B2 com CIV (Vidrion-R, SSWhite), A3 e B3 com CIV modificado por resina (CIV-MR) (Vitremer, 3M); A4, A5, B4 e B5 não foram restaurados. No interior da câmara pulpar de todos os dentes foi colocado tampão acetato. Os subgrupos A1 a A4 e B1 a B4 foram expostos ao peróxido de hidrogênio 38% (Opalescence XtraBoost, Ultradent) por 40 min. Os subgrupos A5 e B5 permaneceram em água deionizada por 40 min. O tampão acetato foi transferido a um tubo de ensaio reagindo com corante violeta leucocristal e peroxidase. A densidade óptica da solução foi avaliada em espectrofotômetro, os valores de absorbância convertidos em microgramas de peróxido e submetidos aos testes de Dunnett, Kruskal-Wallis, ANOVA e Tukey (5%). Verificou-se maior penetração de peróxido nos dentes bovinos (0,79l0,61æg) e humanos (2,27l0,41æg) restaurados com CIV-MR. A penetração do agente clareador foi maior em dentes humanos para qualquer situação experimental. Concluiu-se que a penetração de peróxido depende do material restaurador e que dentes humanos são mais susceptíveis à penetração do agente clareador para o interior da câmara pulpar do que dentes bovinos.It is believe that externally applied bleachings agents could penetrate into the pulp chamber.This study was conducted to evaluate pulp chamber penetration of peroxide bleaching agent in human and bovine teeh, after office bleach technique. All the teeth were sectioned 3mm apical of the cemento-enamel junction and were divided into 2 groups: A (70 third human molars) and B (70 bovine lateral incisor) that were subdivided in: A1 and B1 restored using composite resin (Esthetic-X, Dentsply), A2 and B2 using glass ionomer cement (Vidrion-R, SSWhite), A3 and B3 using resin-modified glass ionomer cement (Vitremer, 3M); A4, A5, B4 and B5 were not restored. Acetate buffer was placed in the pulp chamber and the treatment agent was applied for 40 min as follow: A1 to A4 and B1 to B4 38% hydrogen peroxide exposure and A5 and B5 immersion into distilled water. The buffer solution was transferred to a glass tube where leuco crystal violet and horseradish peroxidase were added, producing a blue solution. The optical density of the blue solution was determined determined by spectrophotometer and converted into microgram equivalents of hydrogen peroxide. Data were submitted to ANOVA and Dunnett, Kruskal-Wallis, and Tukey tests (5%). A higher level of hydrogen peroxide penetrated into the pulp chamber in resin-modified glass ionomer cements groups, bovine (0,79l0,61æg) and human (2,27l0,41æg). The bleaching agent penetration was higher in human teeth for any experimental situation. The penetration of the hydrogen peroxide depend on restorative materials and that human teeth are more susceptible to penetration of bleaching agent into the pulp chamber than bovine teeth.Fundação de Amparo à Pesquisa do Estado de São Paulo (FAPESP