Effect of blood contamination on the push-out bond strength of calcium silicate cements

Abstract This study investigated the effect of blood-contamination on the push-out bond strength of BiodentineTM (BD) and MTA Angelus® (MTA-A) to root dentin over time. Twenty-five teeth were sectioned horizontally to obtain 120 root slices. The lumens were filled with MTA-A or BD: 60 for each cement (30 uncontaminated and 30 blood contaminated). Push out bond strength to dentin was assessed at 24 h (n=10), 7 days (n=10) and 28 days (n=10). Failure modes were classified as: cohesive, adhesive or mixed failure. Two-way ANOVA was used to investigate the interaction between blood contamination vs. hydration period. Mann Whitney test compared different materials in each period, and it also compared the contaminated versus uncontaminated material for each period. Friedman, followed by Dunn`s test, compared periods of hydration for each material, regardless of blood contamination. Failure modes were reported descriptively. The interaction hydration period vs. blood contamination was highly significant for MTA-A (P=0.001) and it was not significant for BD (P=0.474). There were no differences between bond strength of uncontaminated and contaminated BD in any of the periods. Bond strength of uncontaminated MTA-A increased at each time of hydration; but it remained stable over time for blood-contaminated samples. BD had higher bond strength than MTA-A in all periods of hydration. Cohesive failure predominated. Only for MTA-A, the over time bond strength to dentin was affected by blood contamination.

Resumo Este estudo investigou o efeito da contaminação sanguínea na resistência de união do BiodentineTM (BD) e do MTA Angelus® (MTA-A) à dentina, em diferentes períodos. Vinte e cinco dentes foram seccionados para obter 120 fatias de dentina. Os lúmens das fatias foram preenchidos com MTA-A ou BD: 60 para cada cimento (30 não-contaminados e 30 contaminados com sangue). A resistência de união à dentina foi medida por teste push-out em 24 horas (n=10), 7 dias (n=10) e 28 dias (n=10). Os tipos de falha foram classificados como: falha coesiva, adesiva ou mista. Two-way ANOVA foi usado para investigar a interação entre contaminação sanguínea vs. período de hidratação. O teste de Mann Whitney comparou os diferentes materiais em cada período, e comparou as amostras contaminadas e não contaminadas de cada material em cada tempo. O teste de Friedman, seguido pelo teste de Dunn, comparou os períodos de hidratação de cada material, independentemente da contaminação. A análise estatística mostrou a interação entre contaminação sanguínea vs. período de hidratação. Os tipos de falha foram reportados de maneira descritiva. A interação entre contaminação sanguínea vs. período de hidratação foi altamente significativa para o MTA-A (P=0,001), e não foi significativa para o BD (P=0,474). Não houve diferenças entre a resistência de união entre o BD contaminado e não-contaminado independente do período. A resistência de união do MTA-A não-contaminado aumentou a cada tempo de hidratação; mas, permaneceu estável ao longo do tempo para as amostras contaminadas com sangue. BD obteve maior resistência de união que o MTA-A em todos os períodos de hidratação. Falhas coesivas predominaram. A contaminação ao longo do tempo influenciou a resistência de união no grupo MTA-A.

Comparison of Bonding Strength by Cleaning Method of Pediatric Zirconia Crown Contaminated with Saliva or Blood / 대한소아치과학회지

The objective of this study was to compare the shear bonding strength of zirconia after cleaning the crown contaminated by saliva or blood and determine the effect of thermocycling. 180 specimens were embedded in acrylic resin. 20 Specimens in the positive control group were bonded with resin cement without contamination. 20 Specimens in the negative control group were washed with water for 20 seconds and then dried for 10 seconds. 120 Specimens contaminated by saliva or blood were cleaned by using three cleaning methods: 37% phosphoric acid gel, commercial cleanse, and 2.5% NaOCl. All samples were bonded with resin cement and divided into two subgroups: One was not aged, and the other was tested with 30,000 thermocycling. In both groups contamination by saliva and blood, no statistically significant difference was not found in control, groups cleansed by commercial cleanser and 2.5% NaOCl. When the groups cleansed with water and 37% phosphate gel were compared with the control, significantly low shear bond strength was shown. Thermocycling group showed statistically significantly low shear bond stress compared to the groups without thermocycling. When zirconia was contaminated by saliva or blood, its original shear bond strength could be obtained if it was cleaned with commercial cleanser or 2.5% NaOCl.

Prevalence of Bacterial Contamination when using a Diversion Pouch during Blood Collection: A Single Center Study in Malaysia

Background: The implementation of diversion pouches is to minimise the risk of bacterial contamination as the initial blood flow is prevented from entering primary bag collections as it is diverted into a pouch. This study was carried out to determine the prevalence of bacterial contamination in the diversion pouches used  during blood collections in the Transfusion Department of Hospital Seberang Jaya, Penang, Malaysia. Methods: BD Bactec™ Fx instrument detection system was performed on 702 samples of 20 mL of  diverting blood in diversion pouch. The  inocullum  volume was 10 mL for both aerobic and anaerobic bottles cultures and incubated for 5 days in  the BD Bactec™ Fx instrument. Positive sample was flagged by BD Bactec™ Fx instrument and  subculture  to identify the species of organism. Results: The results  showed that of 702 samples, 12 (1.7%) were contaminated. The bacterial species identified were coagulase negative Staphylococcus, Staphylococcus aureus and Gram positive Bacilli. Conclusion: The results  strongly suggest that the usage of diversion pouch is of significant importance in reducing bacterial contamination during blood collection.

Evaluation of the effect of blood contamination on the compressive strength of MTA modified with hydration accelerators

OBJECTIVES: This study was performed to evaluate the effect of blood contamination on the compressive strength (CS) of Root MTA (RMTA) modified with Calcium chloride (CaCl2) and Disodium hydrogen phosphate (Na2HPO4) as setting accelerators over time. MATERIALS AND METHODS: A total of 110 cylindrical specimens of RMTA were divided into 6 experimental groups as follows: Group1, RMTA; Group 2, RMTA modified with CaCl2 (RMTA-C); Group 3, RMTA modified with Na2HPO4 (RMTA-N); Group 4, RMTA contaminated with blood; Group 5, RMTA-C contaminated with blood; Group 6, RMTA-N contaminated with blood. The CS of specimens in all groups was evaluated after 3 hr, 24 hr, and 1 wk. In the modified groups (groups 2, 3, 5, and 6) the CS of five specimens per group was also evaluated after 1 hr. RESULTS: Blood contamination significantly reduced the CS of all materials at all time intervals (p < 0.05). After 3 hr, the CS of specimens in the RMTA groups (with and without blood contamination) was significantly lower than those in the RMTA-C and RMTA-N groups (p < 0.05). The CS values were not significantly different at the other time intervals. In all groups, the CS of specimens significantly increased over time (p < 0.05). CONCLUSIONS: Blood contamination decreased the CS of both original and accelerated RMTA.

Do blood contamination and haemostatic agents affect microtensile bond strength of dual cured resin cement to dentin?

Objective: The purpose of this study was to evaluate the effects of blood contamination and haemostatic agents such as Ankaferd Blood Stopper (ABS) and hydrogen peroxide (H2O2) on the microtensile bond strength between dual cured resin cement-dentin interface. Material and Methods: Twelve pressed lithium disilicate glass ceramics were luted to flat occlusal dentin surfaces with Panavia F under the following conditions: Control Group: no contamination, Group Blood: blood contamination, Group ABS: ABS contamination Group H2O2: H2O2 contamination. The specimens were sectioned to the beams and microtensile testing was carried out. Failure modes were classified under stereomicroscope. Two specimens were randomly selected from each group, and SEM analyses were performed. Results: There were significant differences in microtensile bond strengths (µTBS) between the control and blood-contaminated groups (p<0.05), whereas there were no significant differences found between the control and the other groups (p>0.05). Conclusions: Contamination by blood of dentin surface prior to bonding reduced the bond strength between resin cement and the dentin. Ankaferd Blood Stoper and H2O2 could be used safely as blood stopping agents during cementation of all-ceramics to dentin to prevent bond failure due to blood contamination.

Detection of Bartonella henselae in defibrinated sheep blood used for culture media supplementation

Bartonella henselae was detected in defibrinated sheep blood employed in supplementing a selective bacteria culture medium by nested PCR. We recommended that highly sensitive technical tests be run to ensure a sterile culture medium for Bartonella spp. isolation, since infected blood samples used in preparation could lead to false-positive results.

Effect of blood contamination and decontamination procedures on marginal adaptation and bond strength of composite restorations / Efeito da contaminação com sangue e de procedimentos de descontaminação na adaptação marginal e na resistência de união de restaurações de resina composta

Purpose: To evaluate the effect of blood contamination and different decontamination procedures on marginal adaptation and bond strength of a two-step total-etch adhesive system to dentin. Methods: A total of 135 bovine incisors had the labial surfaces ground to receive cylindrical cavities, and were randomly divided into a control and 8 experimental groups (n=15) according to contamination and decontamination procedures. Freshly collected human blood was applied onto the cavity either before or after light-curing of the adhesive. Four decontamination protocols were tested (drying with paper, water rinsing, phosphoric acid etching, and 10% NaOCl rinsing). The cavities were restored with Adper Single Bond and Filtek Z250 (3M ESPE). The specimens were subjected to thermal cycling before the dye staining test. The cavity floor was removed and the restorations were subjected to a push-out test. Data were analyzed by two-way ANOVA and Tukey's test (α=0.05). Results: Blood contamination after adhesive light-curing increased marginal gap and yielded lower push-out bond strength values (P<0.01). Conclusion: Water rinsing seems to be a reliable procedure for cavity decontamination. The decontamination procedures tested do not recover marginal sealing and bond strength when blood contamination occurs after light-curing of the adhesive.

Objetivo: Avaliar o efeito da contaminação com sangue e de procedimentos de descontaminação na adaptação marginal e resistência de união de um adesivo convencional de dois passos à dentina. Metodologia: Um total de 135 incisivos bovinos receberam cavidades cilíndricas na superfície vestibular, previamente desgastada. Os dentes foram divididos em grupo controle e 8 grupos experimentais (n=15), com base no momento da contaminação e nos procedimentos de descontaminação. Sangue recém-coletado foi aplicado nas cavidades, antes ou após a fotoativação do adesivo. Quatro procedimentos de descontaminação foram testados: secagem com papel, lavagem com água, condicionamento com ácido fosfórico e lavagem com hipoclorito de sódio a 10%. As cavidades foram restauradas com Adper Single Bond e Filtek Z250 (3M ESPE). Os espécimes foram submetidos à termociclagem antes da marcação com corante. O assoalho das cavidades foi removido e as restaurações foram submetidas ao teste de push-out. Os dados foram analisados por two-way ANOVA e teste de Tukey (α=0,05). Resultados: A contaminação após fotoativação do adesivo gerou fendas marginais maiores e resistência de união menor (P<0,001). Conclusão: A lavagem com água parece ser um método confiável de descontaminação. Os procedimentos testados não recuperam o selamento marginal e a resistência de união quando a contaminação ocorre após fotoativação do adesivo.

Clinical study on inversely pressing method with cotton stick after extraction of infusion needle / 中国实用护理杂志

Objective To evaluated the clinical significance of inversely pressing method with cotton stick after extraction of infusion needle to avoid blood contamination,hemorrhage and stagnation.Methods We randomized 356 patients into the experiment group(170 cases)and the control group(186cases).In the experiment group we put the cotton stick inversely on the puncture point and press the point immediately after extraction of the needle with the left thumb.In the control group we put cotton stick on puncture point and proximal vessel after extraction.The conditions of hemorrhage and stagnation were recorded.Results The hemorrhage rate and stagnation rate in the two groups were statistically different (P<0.01).Conclusion To inversely put eotton stick on the puncture point after extraction of infusion needle could lessen hemorrhage and stagnation at the puncture point and avoid contamination.

The effect of contamination on bonding of orthodontic brackets with a self-etching primer/adhesive / 대한치과교정학회지

The purpose of this study was to investigate the influence of water, saliva, and blood contamination on the bonding strenght of metal brackets with a self-etching primer/adhesive to enamel. Ninety-six extracted human teeth were divided into four groups. The brackets were bonded to enamel with a self- etching primer (3M/Unitek Dental Products, Monorovia, California) according to one of four protocols. The teeth were bonded in a dry condition (group D) or in contamination with distilled water (group W), artificial saliva (group S), or fresh human blood (group B). Shear bond strengths were tested using an Instron Universal testing machine. After debonding, bracket and tooth surfaces were examined with a stereomicroscope. In each group, four samples were selected and examined with a Scanning electron microscope of the prepared enamel surface and resin-enamel interface. The results obtained were summarized as follows: Shear bond strength in group D (15.22 +/- 2.86 MPa) and W (16.20 +/- 3.85 MPa) were higher than in group B (12.56 +/- 2.94 MPa) (p 0.05). There was a tendency to have less residual adhesive remaining on the enamel surfaces of group B than group D. The SEM morphology of group D and W showed a more roughened etching pattern than group S and B. Water or saliva contamination on bonding of orthodontic brackets with Transbond plus self etching primer had almost no influence on bond strength. In this study, the blood contaminated group showed the lowest bond strength, but it was above the clinically acceptable bond strength (5.9-7.8 MPa, Reynold, 1975). The results of this study suggest that acceptable clinical bond strengths can be obtained in wet conditions when self-etching adhesives are used.

Prenatal Determination of Fetal Rh, Kell and MN Blood Group Antigens by DNA Analysis of Amniotic Fluid / 대한임상병리학회지

BACKGROUND: Prenatal determination of a blood antigen of a fetus at risk for hemolytic disease of the newborn makes the obstetrician facilitate to take timely procedures such as intra-uterine transfusion or plasma exchange. However, determining the phenotype of a fetal antigen is of limited use because fetal RBCs must be obtained by periumbilical blood sampling which entails considerably greater adverse outcomes than an amniocentesis does. METHODS: Genotypes of Rh, MN and Kell systems using 14 amniotic fluid samples were compared with phenotypes of cord blood. The incidence of maternal blood contamination in 8 amniotic fluid samples which were obtained during mid-trimester was estimated by amplification of variable number of tandem repeat(VNTR) D1S80. The detection sensitivity of each technique was evaluated by artificially mixed samples. RESULTS: All the 14 paired samples of amniotic fluid and cord blood showed identical results between the genotype of amniocyte and the phenotype of cord blood. Of 8 paired samples of amniotic fluid and maternal blood, D1S80 VNTRs of fetuses were evidently amplified and there were no evidence of maternal blood contamination. The detection sensitivity of Rh(E) and Rh(c) genotyping was 0.5% by ethidium bromide staining, while D1S80 VNTR was 10%. Heterozygosity of D1S80 VNTR was 94%. CONCLUSIONS: Genotypes of Rh, MN and Kell systems could be prenatally determined by this technique. Since the heterozygosity of D1S80 VNTR is high up to 94% in Koreans, D1S80 VNTR could be effectively used in determining the maternal blood contamination of amniotic fluid. The prenatal determination of fetal red cell antigen genotypes by this technique will be helpful for the management of sensitized pregnancies at risk for HDN.