Introduction: The purpose of this in vitro study was to evaluate three common gutta-percha solvents’ effectiveness in dissolving three different types of root canal sealers.Materials and Methods: The solubility of three different root canal sealers (AH PLUS, APEXIT PLUS and Endoflas FS) was assessed in xylene, refined orange oil, tetrachloroethylene and distilled water (control). One-hundred twenty samples of root canal sealers were prepared and then divided into three equal groups (n=40). Each group was further divided into four equal subgroups (n=10) for immersion in the respective solvents for a 10 minute immersion period. The mean amount of weight loss was determined for each material in each solvent during the specified immersion period, and the values were subjected to statistical analysis.Results: Xylene exhibited the greatest dissolving efficacy for AH PLUS, followed by refined orange oil and tetrachloroethylene. Xylene was also able to dissolve the greatest amount of APEXIT PLUS, followed by refined orange oil and tetrachloroethylene which were equally effective in dissolving APEXIT PLUS. For Endoflas FS, maximum dissolving efficacy was seen with tetrachloroethylene followed by refined orange oil and xylene.Conclusion: The results showed that xylene, refined orange oil and tetrachloroethylene can be used for the removal of AH PLUS, APEXIT PLUS and Endoflas FS sealers during endodontic retreatment. Further clinical investigations are needed to evaluate the efficacy of these solvents on different sealers.

Introduction: The purpose of this in-vitro study was to investigate the influence of the remaining calcium hydroxide (CH) as an intracanal dressing on the apical sealing ability of three endodontic sealers.Materials and Methods: Sixty-six single and straight canals of recently extracted human permanent maxillary central incisors were used. All canals were prepared and sixty of them were randomly divided into two groups with (group 1) and without (group 2) CH medication.Each of these groups was divided into three experimental groups using AH26 (group a), Dorifill (group b), and APEXIT (group c). Six remained teeth were divided into positive and negative groups of three each. Root canals were filled with gutta-percha and AH26 (groups 1a, 2a), Dorifill (groups 1b, 2b) and APEXIT (groups 1c, 2c) using lateral condensation technique. The apical third of the roots were placed in Pelikan ink for one week. Linear dye penetration was recorded using a stereomicroscope and a digital caliper. Data were compared with analysis of variance (ANOYA).Results: Observed leakage in groups which were filled with APEXIT sealer was significantly different (P<0.002). There was no significant difference among groups which were filled with Dorifill and AH26.Conclusion: Calcium hydroxide did not influence the apical sealing ability of AH26 and Dorifill, while it did improve the apical sealing ability of APEXIT sealer.

Background & Aim: There are a few conditions that prove a sealer to be suitable for use in practice. One of the important factors in a good sealer is its biocompatibility. The purpose of this in-vivo study was to compare the biocompatibility of two types of endodontic sealers; AH26 and APEXIT by using animal model. Materials & Methods: A total of eleven white rats were included in this interventional in-vivo study. After sedation of rats, two sealers (AH26 and APEXIT) were implanted in the subcutaneous tissue of each rat. AH26 was implanted in two sites of subcutaneous tissue in the left side and APEXIT was implanted in two sites in the right side and the control site was designated in between them. In control group, the incisions were made similar to AH26 and APEXIT groups and sutured without insertion of any material. Biopsies were taken from five rats after three days and from the other six rats after thirty days. Histological specimens were studied by pathologist and findings were reported. Data was analyzed using appropriate statistical procedures as well as Mann–Whitney and Kruskal-Wallis tests in order to report the significance level.Results: Although APEXIT caused more inflammation compared to AH26, after 3 and 30 days, but such difference was not statistically significant (P>0.05). However, both sealers initiated mild to moderate inflammation when judged against control group and the difference was statistically significant (P<0.05). Conclusion: Even though AH26 and APEXIT cause inflammation in subcutaneous tissues of rats but they have moderate biocompatibility as the inflammation was graded two in this study according to the pathologic report.

Application of sealer is essential in every obturating technique. Since apical extrusion of sealer during obturation is not uncommon, biocompatibility is of prime importance. Roth's 800, Grossman's formula with ZOE base, APEXIT with calcium hydroxide and Roth's 801 (Apadana Co.) were examined for biocompatibility. 80 male Sprague-Dawley rats with average weight of 800-400 grams were used. All the sealers were mixid according to the manufacture's instructions and placed into polyethylene tubes. Polyethylene tubes were selected as controls. The animals were classified in four groups, each containing 20 rats. After incisions, the materials were implanted subcutaneously in dorsal surfaces of animals. The materials were evaluated 4, 10, 30 and 60 days after surgery. After these periods, four rats of each group were selected and sacrificed with high doses of chloroform. After dissecting, the samples were inserted into 10% formalin solution and examined single blindly by oral pathologist in two stages at the Tehran dental faculty. The samples were classified on the basis of inflammation into four groups. Group 0 (Zero) (without inflammation), group 1 (with mild inflammation), group 2 (with moderate inflammation), group 3 (with severe inflammation). All the results were statistically evaluated by Kruskal-Wallis and Mann-Whitney tests. In the 4th day, in the control group moderate inflammation were observed which is statistically significant. In the 10th day, in the control group mild inflammation and in the other three remaining groups sever inflammation were observed which is statistically significant. In the 20th day, in the control group no,inflammation and in the APEXIT group and Grossman's group moderate inflammation and in the Apadana's sealer group moderate to severe inflammation were seen which were statistically significant. In the 60th day, there was no inflammation in the control group. In Grossman's sealer group mild inflammation and in APEXIT's sealer group mile to moderate inflammation were observed. In statistical manner, there is no significant difference between the Apadana's Roth sealer and APEXIT's sealer but between these two sealers and Grossman's and the control group, there are significant statistical difference with P=0.008.

Background & Aim: Most of the endodontic ally treated teeth require extensive restorations, including dowel and core. Post space preparation involves differen stages. Someclinicians make it immediatelyafter the conletion of RCT while some prefer if done several days after the root treatment is comleted. To compare the performance immediate and delayed post space several important factors such as apical microleakage and type of sealer affect the results of final treatment. This research was carried out to compare Apical Microleakage in preparation immediateand delayed post space preparation using two different sealers (AH26 and APEXIT). Material and Methods: The method of intotal, 96 single rooted human teeth were selected and divided randomly into four groups in this study was experimental. Two positive and negative control groups were also designatol for this study. Results: Result revealed no significant difference of microleakage level between two groups (delayed and immediate) using two differen types sealer (AH26- APEXIT). Conclusion: It seems that the usae of the sealer has no effect on micro leakage level of the root fillings white different operatory systems of immediate and delayed had a significant effect on the result of microleakage measuremen

The more clearly the clinician comprehends the processes of clinical perception and of linking the experience with explanation, the more thoughtfully clinical students can be guided to construct an accurate clinical memory of cases, and to construct a sound working knowledge structure from their personal examined experience. The structuring of the steps of clinical learning is intended as a check list to optimise their coverage, and as a framework for examining and codifying clinical working knowledge within which continuing education can be conducted.

Background: Monotherapy is not usually effective in the treatment of hirsutism. Objective: Comparison of two therapeutic regimens in the treatment of hirsutism. Patients and Methods: In this open parallel controlled clinical trial, 101 patients suffering from hirsutism were randomly divided into two equal groups. Fifty patients were treated with spironolactone ( 50 mg /day) PLUS cyproterone compound (from 5th to 26th day of menstrual cycle) and the other group (51 patients) received cyproterone acetate 50 mg /day (from 5thto 14thday of menstrual cycle) in addition to the above mentioned drugs for 6 months. The serum level of sex hormones and hirsutism score (Ferriman-Gallway) were determined before and after treatment. T-test, chi-2 test and linear regression analysis were used for data analysis. Results: Mean hirsutism score was 22/12±0/34 in first group and 22/15±0/34 in second groups before treatment. Hirsutism score was reduced to 12/74± 0/32 after treatment with 3 drugs and reduced to 16/73± 0/35 after treatment with two drugs. This reduction was significantly more in the first group after adjustment for other confounding variables (P<0/001). Conclusion: These two therapeutic regimens were both effective in the treatment of hirsutism without serious hepatic, renal and metobolic side effects. Treatment with 3 antiandrogen drugs was more effective in reduction of hirsutism scores.  

Background: Root canal sealer is a helpful material to increase the quality of root the canal obturation. The aim of this study which has been carried out in vitro and by the use of dye penetration method was comparison between apical leakage of four root canal sealers. Material and Methods: In this study, 140 anterior natural teeth having one canal each, were divided into 4 experimental groups and 2 positive and negative control groups. Each of the four mentioned groups were obturated with one of four sealers; 1-AH26, 2-ZOE, 3- APEXIT, 4-Dorifill and gutta percha with lateral condensation method. After decalcification procedures the teeth were put in india ink and centrifuged 3000 rpm for 15 minutes, and were left immersed in the dye for 72 hours . After longitudinally sectioning , the rate of dye penetration were studied by 3 dentists using double blind method , the results were analyzed by Anova and t-test Results: The mean leakage of groups were as follows: AH26:3.08mm, ZOE:3.25mm, Apex it: 3.82mm, Dorifill:3.86 mm. There was no remarkable statistically different between AH26 and ZOE in leakage rate but the difference in the results between Dorifill and ZOE were considerable. Conclusion: The results showed that the Ah26 sealers are the best from the apical leakage stand point. It needs a clinical long term study in human or animal.