Relation between Calcium Loss and Its Effect on Microhardness of Root Canal Dentin Following Treatment With 17% Ethylene Diamine Tetraacetic Acid(EDTA) at Different Time Intervals: An Ex-Vivo Study.

Decalcification and its effect on microhardness of root canal dentin by an aqueous solution of 17% EDTA at different time intervals were studied.Single rooted forty extracted human premolar teeth after adequate processing and embedded with acrylic resin were randomly divided into 8 groups based on different time intervals. Each sample group was assessed for Ca²⁺ release into the test solution by Atomic Absorption Spectrophotometer, respectively and then were subjected for microhardness testing.17% EDTA and 0.9% Saline, test solutions were used; EDTA was adjusted to 7.5 pH. Data analysis was done by One Way analysis of variance (ANOVA) and the comparison of means was done by using Tukey’s multiple comparison tests. The decalcifying activity of 17% EDTA solution was time dependent and increased immersion time showing very high significant influence on the amount of calcium extracted (<strong>F=154.304, p). The reduction in microhardness for 17% EDTA solution was time dependent and increased immersion time showing very high significant decrease in the microhardness among the different time intervals tested (<strong>F=249.925, p < 0.0005</strong>).Effect of 17 % EDTA solution as root canal irrigant is time dependent as evidenced by dentin microhardness reduction.

The effect of 0.5% sodium hypochlorite and 2% glutaraldehyde spray disenfectants on irreversible hydrocolloid impression material.

Infection control has assumed prime importance in dentistry. It is a prime concern in prosthodontics as well, where impressions materials are most commonly used. Impression materials can act as a medium for cross infection. To prevent cross infection many products are being developed. Among them 0.5% Sodium hypochlorite and 2% Glutaraldehyde are considered effective. This study was done to asses the efficacy of 0.5% Sodium hypochlorite and 2% Glutaraldehyde on irreversible hydrocolloid impression material. The result of the study indicated that they are effective against both Gram positive and Gram negative organisms and their use is recommended.