Evaluation of different materials used for post construction and stress distribution in the radicular dentin using finite element method

This study was designed to evaluate the stress distributions of different post materials in radicular dentine for providing a useful clinical guideline. In this experimental study, 5 three - dimensional models of maxillary central incisors were simulated by using ANSYS software and Finite Element Method. The models included: 1] Stainless Steel post 2] Titanium post 3] Carbon fiber post 4] Glass fiber post, and 5] Quartz fiber post. A composite core and PFM crown was constructed for all samples. Each model contained gingival, cortical and spongy bone, PDL and gutta-percha as well. All specimens were subjected to a compressive load at 45-degree angle to its long axis with a constant intensity of 100N. In all models there were two stress concentration sites: 1- a point between middle third and cervical third of the root and 2 - the cervical edge of the root. The amount of stresses between middle and the cervical third of fiber reinforced posts were nearly 1 MPa greater than those of the metallic ones. Compared to other materials, the metallic posts caused less stress in the radicular dentin and therefore are recommended for clinical use. Among fiber reinforced posts, Quartz fiber post showed the lowest stress peak

relationship between serum vitamin D level, coronary artery diseases and the associated risk factors in female carpet weavers

Regarding some evidences, the mortality of coronary artery diseases may be related to vitamin D [VD] deficiency. This kind of deficiency is more common among female carpet weavers. To determine the relationship between serum vitamin D level, coronary artery diseases [CAD] and the associated risk factors in female carpet weavers. This case-control study was conducted on 460 postmenopausal carpet-weavers and noncarpet- weavers in the villages of Isfahan with similar socio-economic conditions. The participants initially underwent the clinical examinations and electrocardiography and if necessary, ecocardiography and exercise tests. Blood pressure, blood lipids and both serum and dietary vitamin D were measured and a questionnaire was completed for every participant. The presence of CAD was determined based on the Rose questionnaire and/or Minnesota electrocardiography coding system. The frequency of CAD and the mean values of other factors were insignificant between two groups [p>0.05]. There was no statistical association between the serum vitamin D level and some of the CAD risk factors among carpet and non-carpet weavers and persons with or without CAD [p>0.05]. There was only a direct relationship between abdominal obesity and serum vitamin D level [OR=0.69, p= 0.03]. Regarding our data, no relationship was found between CAD and serum vitamin D. However, more investigations including the determination of serum and dietary calcium, serum phosphorus and PTH are needed. Also a research, analyzing the vitamin D receptor [VDR] gene polymorphisms is proposed

[Preparation and physicochemical evaluation of diazepam suppository in infantile febrile seizures]

Introduction and Objective: febrile seizures are the most common form of convulsions in childhood. Rectal diazepam in solution is very suitable for acute treatment of febrile convulsions. Furthermore, diazepam suppositories are used prophylactically. The aims of this study were to prepare a suitable and efficient formulation of diazepam suppository and to elucidate the influence of suppository base on dissolution rate using various techniques

Materials and Methods: suppositories containing diazepam [5 mg] were manufactured with Witepsol H35, PEG300 plus PEG4000, PEG1000 plus PEG4000 and PEG1000 plus PEG6000, by the fusion method. Physical characteristics of suppositories such as weight variation, liquefaction time, mechanical strength, content uniformity and percent of drug released were studied and compared to a brand of diazepam suppository. Dissolution testing was done by three methods: the USP basket, paddle and dialysis cell

Results: the results showed that the release of drug from PEG1000+4000, PEG1000+6000 and Witepsol H35 is greater than PEG300+4000 and brand one. In dialysis cell method drug was released slower than the paddle and basket methods

Conclusions: it was recognized that a dissolution testing method would be useful in both formulation design and also in quality procedures relating to the products

Prevalence of hypertension and associated risk factors in Isfahan, Islamic Republic of Iran

A population-based cross-sectional survey was conducted to determine the mean levels of blood pressure and prevalence rates of hypertension and to identify differences in the prevalence of other risk factors in hypertensive and nonhypertensive people. A total of 8624 men and women > or = 19 years were randomly selected. Overall, 18.0% [16.8% males and 19.4% females] had systemic hypertension. The mean levels of systolic and diastolic blood pressure and the prevalence of hypertension increased with age, but no significant differences were found between the sexes when adjusted for body mass index. There was a high prevalence of obesity, hyperlipidaemia and diabetes mellitus among hypertensive people compared with nonhypertensive. Our study suggests that the prevalence of hypertension in Isfahan is greater than supposed