[Evaluation of antimicrobial effects of different calcium hydroxide preparation methods with direct exposure test]

Calcium hydroxide has a pronounced antimicrobial activity against most of the bacterial species found in the root canal and now is widely used as an intracanal medicament in endodontic therapy. The aim of this study was to evaluate the antimicrobial effect of different calcium hydroxide preparations with Normal saline, Lidocaine 2%, Chlorhexedin 2% and 0/2%, Iodine Potassium Iodide 2% and Glycerin on Entrococcus faeealis with direct exposure method. For conducting this experimental in-vitro study 375 sterile paper points were contaminated with the microbial suspension of Entrococcus faecalis. The samples were placed in sterile dishes and covered with creamy mixture of six different calcium hydroxide preparations. After 1.3, and 7 days tile paper points were immersed in test tubes containing BHI. Microbial growth was evaluated by turbidity in culture mediums. Data obtained showed that all of tested materials had perfect antimicrobial action but only in calcium hydroxide with Chlorhexidine 2% and 0.2% groups perfect antimicrobial action and no microbial growth was observed after 24 hours. Regarding the results of this study it is concluded that the vehicle of calcium hydroxide has not any significant effect on its antimicrobial activity, however, more studies on the effect of vehicles of chemical properties of calcium hydroxide such as its diffusion in similar conditions of root canal system, are needed

Different duration of colchicine for preventing recurrence of gouty arthritis

Gout is a Common recurrent clinical syndrome characterized by increased serum uric acid and recurrent attacks of acute arthritis. Colchicine is used for Prophylaxis against recurrence of arthritis, but the duration of its administration has mentioned variable. In this study, optimal duration of prophylactic colchicine for prevention of gouty arthritis was assessed. In a clinical trial 190 patients with gouty arthritis divided randomly to group 1,2and 3 and received colchicine for 3 to 6, 7 to 9 and 10 to 12 months then colchicine discontinued and the patients followed one year for recurrence of arthritis. Result assessed by survival analysis with Kaplan 'Meier method. The probability of recurrence of arthritis [in order of duration of colchicine prophylaxis] was 54%, 27.5% and 23%, respectively. The difference between group one and others was statistically significant, but between group 2 and 3 was not statistically significant. The most suitable duration of colchicine prophylaxis that accompanied with lower recurrence rate was 7-9 months, which seems more cost -effective than 10-12 months regimen