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Similar expression of through-and-through fluid movement along orthograde apical plugs of MTA Bio and white Portland cement.

AIM
To compare the sealing ability of four hydraulic cements when used as an apical plug in teeth with wide-open apices.


METHODOLOGY
A sample of 70 maxillary central incisors were divided into four groups (n = 15) and a further 10 teeth served as controls. An artificial open apex was created in the teeth using Gates Glidden drills numbers 6-1 in a crown-down manner until the size 1 bur passed through the foramen. A divergent open apex was prepared to a size of 1.24 mm at the foramen by retrograde apical transportation using a number 8 (0.60) Profile Series 29 0.4 taper instrument inserted to the length of the cutting blade. In G1, the open apices were repaired with WMTA Angelus whilst in G2, G3 and G4 MTA Bio, Pro-Root MTA and Portland cement was employed respectively. Each root was assembled in a hermetic cell to allow the evaluation of fluid filtration. Leakage was measured by the movement of an air bubble travelling within a pipette connected to the teeth. Measurements of the air bubble movement were made after 10 min at a constant pressure of 50 cm H(2)O. The Kruskal-Wallis H-test was applied to the fluid flow data to detect differences between the experimental groups (P < 0.05).


RESULTS
Fluid movement occurred in every sample but was variable in all the experimental groups, ranging from 0.61 to 2.45 microL min(-1). There was no significant difference in mean fluid flow between the experimental groups (P > 0.05).


CONCLUSIONS
Fluid movement through teeth with open apices and filled with four hydraulic cements was similar. All cements allowed fluid movement.