Effects of pressure and measurement time on the fluid filtration method in endodontics

The purpose of this study was to evaluate the influence of the measurement time and the pressure on the outcome of a fluid filtration test. Thirty-six roots were prepared with a Profile device and filled with Thermafil. The leakage along the filling material was recorded under a 15 cm H2O pressure (n = 18) or a 150 cm H2O pressure (n = 18) at 3 min, 1 h, and 24 h. The fluid flow expressed as microl min(-1) decreased with an increased measurement time (p = 0.001) and was higher in the high pressure group (p = 0.001). The fluid flow of this study, where all of the teeth were filled with the same technique, ranged from 3.8 x 10(-5) microl min(-1) cm H2O(-1) to 43 x 10(-5) microl min(-1) cm H2O(-1), depending on the pressure and measurement time. This shows the need for standardization to compare the results from various studies.