RESUMEN
Pre-eclampsia affects approximately 5-8% of pregnant women. The aim of this study was to compare the serum level of Lactate dehydrogenase [LDH], Homocystein, Hemoglubin and platelet in pregnant women diagnosed as pre-eclampsia and a normal group in Gorgan city, Northeastern Iran from 2007-2008. In this case control study, 50 cases of pre-eclampsia were compared with the control group women hospitalized in Dezyani hospital. Pre-eclampsia criteria were: Blood pressure more than or equal to 140/ 90 mm hg and Proteinuria greater or equal to 300 mg/ 24 hours urine sample in the third trimester. Hemoglobin, platelet, LDH and hemocystein were measured. Data were analyzed by the mean of SPSS-14 program and Chi-2 or t-student were used. The difference of BMI and family incomes was significant between two groups [P-value<0.01]. LDH level was not statistically different between healthy and pre-eclamptic individuals. Six cases [12%] in controls and 9 cases [18%] in pre-eclamptic group had thrombocytopenia [P-value>0.01]. Hemocystein level was more than normal range in five patients with pre-eclampsia [P-value<0.001]. In this study, hemocystein level was significantly higher in pre-eclampsia patients but LDH, hemoglobin and platelet level had no significant difference
RESUMEN
Different alternative surface treatments, which have not been fully investigated, have been suggested to improve bonding to zirconia. The aim of this study was to compare microtensile bond strength of self-adhesive resin luting cements to zirconia following different surface treatments., Three blocks of zirconia [Cercon, Degussa, Germany] and three composite blocks [Z100, 3M, ESPE, USA] with 11x11x5 mm dimension were made. The blocks were divided into three groups. The ceramic blocks were cemented to the composite blocks using G-Cem [GC, Japan] according to the manufacturer's specifications. All samples were stored in 37°C distilled water for 24 hours and later sectioned in two axes using diamond disk to obtain bar shape specimens with a cross-sectional area of approximately 1mm[2] and 10mm long [n=12]. Specimens were stored in 37°C distilled water for 72 hours and thermocycled for 2000 cycles [5°C/55°C]. Each specimen was then attached to a microtensile test device. Bond strength was measured with crosshead speed of Imm/min. Failure modes were examined under stereomicroscope [x40]. Representative specimens were observed by scanning electron microscopy [SEM]. Bond strength data were analyzed with one way ANOVA and Tukey tests [a-0.05]. Alloy Primer subgroup [49.64 +/- 7.02] had a significantly higher bond strength than silane [42.12 +/- 4.2] and silicoating with silanopen [21.78 +/- 4.7] [p<0.0001]. Silanopen had the lowest bond strength in this group. SEM observation indicate that ceramic surface in silanopen group had fewer irregularities. Primers containing MDP functional monomer like Alloy Primer affect the durability of self adhesive resin cement [G-Cem] bond strength to zirconia
Asunto(s)
Resistencia a la Tracción , Recubrimiento Dental Adhesivo , Cementos de Resina , Resinas CompuestasRESUMEN
The sealing ability of different endodontic sealers has been evaluated using micro-leakage tests and/or measuring their bond strength [adhesion] to dentin and gutta percha. However, the micro-leakage studies do not determine the location of the micro-leakage. Therefore, to determine whether the micro-leakage occurs in the dentin-sealer or the gutta percha- sealer interfaces, the bond strength studies are required. The purpose of the present study was to measure the bond strength of AH26 and Dorifill to dentin and gutta percha and to compare their relationship with their apical microleakage values using electrochemical test. In this laboratory study, to evaluate the tensile strength of AH26 and Dorfill, the dentinal coronal surface of the twenty four extracted maxillary and mandibular first and second molars were used. Twenty four disk shape specimens of the gutta-percha were prepared. Two groups of sealers [AH26, Dorifill] were placed within the aluminum customized cylinders [n=48] and stabilized on the dentin and gutta-percha. The tensile strength of each sealer with dentin; and gutta- percha were measured separately by a universal testing machine [zwick] in four groups [12 samples in each groups]. The data were analyzed using independent samples t-test. To evaluate the sealers' apical leakages using electrochemical method, 36 maxillary and mandibular canines were used. The selected teeth randomly divided into 2 groups [16 sample in each group] and 4 teeth as control. After canal preparation, each group was filled with one of the sealers and guttapercha using lateral condensation method. Measurment of current flow through the test system were recorded as a voltage drop across the 100-ohm resistance by a digital multimiter every 72 hour. The data were analyzed using Mann- Whitney test. The bond strength of AH26 to both dentin and gutta-percha was significantly stronger than Dorifill. AH26 had a significantly lower magnitude of apical microleakage than Dorifill. The results of this study showed a direct relation between sealers' bond strength to dentin and gutta-percha with their resistance to apical micro-leakages