The effect of powder:liquid ratio and pre-mixing on sealing properties of Roth 801 sealer.

To investigate the sealing ability of Roth 801 sealer mixed using two different powder/liquid ratios and prepared up to seven days prior to canal obturation. Of the 152 maxillary anterior teeth endodontically instrumented for this study, 144 were randomly assigned to the treatment group, and eight were assigned to the control group. Of the 144 teeth in the treatment group, 72 were obturated using gutta-percha and Roth 801 sealer mixed with a 10:1 ratio, while the remaining 72 were obturated with a sealer ratio of 7.5:1. Within both treatment groups, the teeth were further subdivided into six groups of 12 teeth based upon the amount of time between sealer mixing and canal obturation, which varied from 0 days to seven days. Teeth were analyzed with fluid filtration either immediately after obturation or 14 weeks after obturation. The data were analyzed using a three-way analysis of variance. For teeth tested at the time of obturation, leakage decreased for older sealer, p < 0.0001. After the 14-week storage period, there was no significant difference in leakage. No significant differences were noted between either powder/liquid ratios. Pre-mixed Roth 801 sealer maintained an apical seal when prepared up to seven days prior to canal obturation. Varying the powder/liquid ratio of Roth 801 sealer did not significantly affect the apical seal.