Comparative in-vitro evaluation of three chelator pastes.
OBJECTIVE
To compare the effect of three paste chelating agents on the root dentine of extracted teeth: Calcinase-Slide (lege artis, Dettenhausen, Germany), Glyde-File (DeTrey/Dentsply, Konstanz, Germany), RC-Prep (Premier, Norristown, USA).


METHODS
Ten slices of root dentine were covered with one of the chelating agents for 30 s, 1 min and 2 min and irrigated with 5 mL H2O2 and NaOCl. This was repeated five times. Pre- and postoperative Vickers hardness of root dentine was measured. Twenty slices of root dentine were covered with 0.1 mL of the chelating agents for 3, 6 and 9 min. Differences between pre- and postoperative weight were recorded. Ten root canals of extracted teeth were enlarged five ISO-sizes with 0.1 mL chelator paste for each file. The teeth were split longitudinally and cleanliness of the root-canal walls was evaluated under the SEM using a four-score evaluation index. Results were statistically analysed using the Wilcoxon-Mann-Whitney test, the Friedman test and the Kruskal-Wallis test with P<0.05 for all tests.


RESULTS
No significant differences between the chelating agents were found in terms of changes in dentine hardness. Loss of hardness increased significantly with increasing time of contact of the chelating pastes with dentine. There were significant differences between the three chelating agents and the control for loss of weight. After 3 min there was no significant difference between the chelating agents, after 6 and 9 min Calcinase-Slide showed significantly more weight loss than RC-Prep; after 6 min Glyde-File showed significantly more weight loss than RC-Prep. In the coronal and middle parts of the root canals, the cleaning ability of Calcinase-Slide was significantly better than of RC-Prep and Glyde-File; in the apical third no differences could be found.


CONCLUSIONS
Under the circumstances of this in vitro study, the three chelator pastes evaluated had no or only slight differences in terms of weight loss, changes of Vickers hardness in root dentine and cleanliness of root-canal walls. The use of a chelating agent may be useful to enhance cleanliness of the coronal and middle part of the root canal.
Department of Operative Dentistry, Preventive Dentistry and Periodontology, University of Göttingen, Germany. michael.huelsmann@med.uni-goettingen
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Hülsmann
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Heckendorff
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Schäfers
D000077463:Carbamide Peroxide; D002614:Chelating Agents / Q000008:administration & dosage / Q000494:pharmacology*; D016009:Chi-Square Distribution; D003786:Dental Pulp Cavity / Q000187:drug effects*; D003804:Dentin / Q000187:drug effects*; D004338:Drug Combinations; D004492:Edetic Acid / Q000008:administration & dosage / Q000494:pharmacology; D006244:Hardness / Q000187:drug effects; D006801:Humans; D008855:Microscopy, Electron, Scanning; D009824:Ointments; D010545:Peroxides / Q000008:administration & dosage / Q000494:pharmacology; D018915:Root Canal Preparation / Q000379:methods; D016369:Smear Layer; D018709:Statistics, Nonparametric; D014508:Urea / Q000008:administration & dosage / Q000031:analogs & derivatives* / Q000494:pharmacology
D002614:Chelating Agents; D004338:Drug Combinations; D009824:Ointments; D010545:Peroxides; D000077463:Carbamide Peroxide; D014508:Urea; D004492:Edetic Acid