Comparison of the calcified barrier formed by calcium hydroxide paste and MTA during apexification procedure

Abstract

ABSTRACT
Background: Apexification had been found to be high effective in the management of immature necrotic
permanent teeth. It is the induction of an apical calcified barrier or the creation of an artificial barrier across an open
apex against which filling material can be packed. The aim of this study was to evaluate appearance, thickness,
and time needed for the apical calcified barrier formation by using calcium hydroxide paste and MTA.
Materials and Methods: Forty premolars with single root canals were prepared to simulate an open apex of 1mm
diameter. These roots were divided into 2 groups: group A consists of 20 roots filled with Ca(OH)2 paste and group B
consists of 20 roots filled with MTA. Each root was placed in a polyethylene vial containing synthetic tissue fluid. The
presence of apical calcified barrier of each root was checked at weeks 1, 2, 3, 4, 5, 6, 7, and 8. At the end of the test
period, each root was taken out and the thickness of the formed apical calcified barrier was measured by vernier.
Results: All samples have calcified barrier at the end of 8 weeks. This barrier formed in 55% of the roots filled with
Ca(OH)2 paste at the beginning of 3rd week and in 40% of the roots filled with MTA at the beginning of 5th week. The
calcified barrier that formed by Ca(OH)2 paste had a chalky and irregular surface while that formed by MTA had a
glassy and regular surface. There was a highly significant difference in the thickness of this barrier between these two
groups.
Conclusions: The apical calcified barrier can be formed without the involvement of Hertwig’s epithelial root sheath.
There was a difference in the appearance of the calcified barrier formed by Ca(OH)2 paste and MTA. The apical
calcified barrier formed earlier and faster and was thicker in the roots filled with Ca(OH)2 paste as compared with
those filled with MTA.
Keywords: Apexification, Calcium hydroxide past, MTA. J Bagh Coll Dentistry 2010; 22(1):98-100.