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Background and aimsPresence of diabetes mellitus (DM) during pregnancy is important cause of maternal and fetal complications. Studies that address the effect of DM on pregnancy and birth outcome are scarce in Ethiopia. The aim of this study was to determine the effect of DM on maternal and birth outcomes in Wolaita Zone, Southern Ethiopia.MethodsA retrospective cohort study was done to compare maternal and birth outcomes of mothers with DM and non-DM who received maternity service in three hospitals and four health centers in Southern Ethiopia. A total of 136 exposed (with DM) and 272 unexposed (non-DM) mothers were included in the study. Data were extracted from medical records of mothers by experienced and trained data collectors. Means were compared for continuous variables. Logistic regression analysis model was used to check the effect of DM on pregnancy and birth outcome. Risk Ratio was calculated and p value less than 0.05 was considered statistically significant.ResultsPregnancy of diabetic mothers was significantly complicated by pre-eclampsia when compared with non-diabetic mothers, (RR = 1.8: 95% CI; 1.2–2.7). The risk of macrosomia was higher for neonates of diabetic mothers than non-diabetic mothers, (RR = 1.9: 95% CI; 1.3–2.7). From multivariate analysis, mothers with DM were 2.9 times more likely to be delivered by caesarean section than non-diabetic mothers (RR = 2.9: 95%CI; 1.3–6.2) and the risk of pre-term delivery was 2.5 times higher among mothers with DM, (RR = 2.5: 95% CI; 1.1–6.2).ConclusionsDiabetes mellitus among pregnant mothers is associated with increased risk of pre-term delivery, macrosomia and maternal complications of pre-eclampsia and caesarian delivery. Early detection and management of DM should be one of the key activities to improve maternal and child mortality and morbidity.  相似文献   
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Statement of problem

Components have been introduced that allow the screw channel of an implant crown to be angled lingually and the screws to be tightened in a non-axial direction to the implant. Information is lacking as to how the removal torque value (RTV) and force to failure (FTF) of these components compare with those of conventional screws.

Purpose

The purpose of this in vitro study was to evaluate and compare the RTV and FTF values of cyclically loaded implant-supported restorations. Specifically, values for conventional axially tightened gold screws were compared with those for non-axially tightened screws aligned at 3 different angulations.

Material and methods

A total of 28 external hexagon implants were embedded in acrylic resin and divided into 4 groups. Simulated restorations were fabricated on abutments capable of different screw channel angulations. Dynamic abutments (DA) were waxed at different angulations and then cast. Simulated restorations were placed on the implants and tightened: group 0GS: 0-degree angulation gold screw tightened to 35 Ncm (control group); group 0DAS, 0-degree angulation with dynamic abutment (DAS) screw; group 20DAS: 20-degree angulation with DA screw; group 28DAS: 28-degree angulation with DAS screw. In groups 0DAS, 20DAS, and 28DAS, the DAS screw was used and tightened to 25 Ncm. Screw removal torque values were recorded by using a digital torque gauge at baseline and, after reaching cyclic fatigue, by using a dual-axis mastication simulator for 1 200 000 cycles. The fracture strength (FS) of the implant restorations was tested under compression until failure by using a universal testing machine. Differences between baseline and removal torque (ΔRT) were calculated. Statistical analysis was performed by using 1-way ANOVA for ΔRT and FS separately (α=.05).

Results

ΔRT and FS values were not significantly different among the groups (P>.05). The screw fractured in 5 of 28 specimens (17.8%); the remaining specimens failed with fracture of the implant.

Conclusions

The removal torque and FS values of the angulated abutment screw were comparable to those of the gold screw. Angulation of the abutment had no significant influence on the screw removal torque values.  相似文献   
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