Evaluation of three thermoplasticized gutta‐percha filling techniques using a leakage modelin vitro

Publisher Website
Google Scholar
Abstract
Summary. In an experimetal model the leakge of three endodontic filling techniques using the thermoplasticity of gutt‐percha, was compared with the leakge occurring in canals filled by lateral condensation.Forty‐six blocks of artificial dentine, comprised of hydroxyapatite and polyethylene, containing standardized curved and prepared ‘root canals’, were mounted in open‐ended tubes. Five groups of eight canals each were obturated by: (i) a combination of lateral condensation and thermomechanical compaction (hybrid technique), (ii) by lateral condensation with the use of a heated spreader (Endotec), (iii) by injection of low‐temperature thermoplasticized gutta‐percha, (iv) by conventional lateral condensation performed by an experienced operator, and (v) by lateral condesation performed by an inexperienced operator. Two blocks with canals left open served as positive controls. Four blocks without canals served as negative controls. At the coronal end of the canals the tubes were filled with 0.5 per cent butyric acid and 0.1 per cent valeric acid in water. The apical reservoir was filled with 0.1 per cent valeric acid. The tubes were closed with rubber membrace stoppers at both ends. The butyric acid was the material to leak, the valerate served and an internal standard. Six and 11 days after obutration, samples which were drawn from the apical reservoir, were acidified and injected into a gas chromatograph for butyric and valeric acid concentration analysis. Six day samples did not show a statistical difference in leakage among groups. Eleven‐day samples, after 5 days of forced leakage through elevated pressure at hte coronal reservoir did, however, show a statistical difference using one‐way analysis of variance. The Student‐Keuls multiple comparison test revealed that the group filled with the use of the Endotec had significantly less leakage than any of the other groups. Nodifference was observed in leakage between the tow lateral conddensation group. Correspondence: Dr H. W. Kersten, Academic Centre for Dentistry Amsterdam (ACTA), Department of Cariology and Endodontology, Louwesweg 1,1066 EA Amsterdam, The Netherlands.