Microleakage of IRM® used to restore endodontic access preparations

Abstract

The effect on microleakage of varying the powder-to-liquid ratio (P/L) of IRM used to restore endodontic access preparations was evaluated. Crowns of noncarious, nonrestored extracted human teeth were used in this study. Microleakage was measured using a fluid filtration technique prior to access preparation to obtain control measurements. After access preparation, IRM restorations were placed using P/L of 2, 3, 4, 5, and 6 g/ml, using the manufacturer's recommended dispensing scoop and dropper, and using 2 P/L in a new capsulated IRM delivery system (IRM CAPS). Microleakage measurements were made after various time intervals and after thermal stress. The results indicated that the lower P/L provided the best seals. All groups demonstrated significant microleakage measurements after thermal stress. Significantly greater microleakage measurements were obtained with the P/L of 6 g/ml and the manufacturer's recommended dispensing scoop and dropper. A P/L of 2 g/ml demonstrated less microleakage than the other groups tested.

Time‐dependence of coronal seal of temporary materials used in endodontics

“…This could be attributed to the different methodologies, especially when techniques for measuring microleakage are considered. This ratio leads to a thick mixture with low viscosity then difficulty in handing of the cement (applying and condensing) (25)(26)(27). In this study IRM and ZP cements were mixed in a powder/liquid ratio according to manufacturer's instructions (5.5-6/1, 5/1 respectively).…”

Temporization for endodontics

“…IRM is a ZOE cement reinforced with polymethyl methacrylate. This reinforcement provides the restoration with improved compressive strength, abrasion resistance and hardness (Blaney et al . 1981, Anderson et al .…”

“…Following these recommendations usually results in a less than ideal seal but provides more optimum physical properties. The use of less powder provides a better seal at the expense of minimally compromising the physical properties (Pashley et al . 1988, Anderson et al .…”

Role of provisional restorations in endodontic therapy

“…This reinforcement provides the restoration with improved compressive strength, abrasion resistance and hardness. [26] The manufacturers recommend the use of IRM as a temporary restoration for cavities for up to 1 year using a powder to liquid ratio of 6:1 (g ml −1 ). Following these recommendations usually results in a less than ideal seal but provides more optimum physical properties.…”