Abstrait

Effect of EDTA on the Bovine Radical Dentine: An Integral Statistical Analysis in R Language

Alberto Marcial Manlla, Maria Mercedes Salas Lopez, Maria Macarena Puca Castronuevo, Maria Luisa De La Casa and Maria Elena Lopez

Background/Purpose: The use of 17% EDTA is frequent in endodontics during the cleaning and shaping of the root canals. The aim of the present study is to analyse the chemical action of 17% EDTA on the weight and calcium content of the bovine root dentin through the application of an integral statistical analysis of pared data adjusted to the parametric assumptions. Materials and Methods: Teeth of freshly slaughtered young bovines recently killed devoided of crown and root, were longitudinally sectioned in halves mesial and distal directions. The pulp was extracted with cotton forceps and the cement was scraped with curette and scalpel. Pieces of root dentin were washed with distilled water and dried at 20°C. Each half of root was contacted for 30 minutes with 2 ml of 17% EDTA; the other half was placed the same time in bidistilled water. Each piece was weighted before and after the contact. Previous acid hydrolysis, atomic calcium in the quelant solution was determined through atomic absorption spectrometry. For the statistical analysis the t-test for related samples was applied, since the variables adjusted to a normal distribution and showed equality of variances. In R language, the experimental data were exposed to the analysis of the parametric assumptions, to the tests to compare two paired samples and to the analysis of correlation. Results: A significant difference was evidenced between the weight of the dentin pieces before and after 30 minutes contact with 17% EDTA. A direct but non-significant association between calcium tramped by 17% EDTA and decrease in weight of the dentin was also found. Conclusion: The decrease in the dentinal weight at contact with 17% EDTA for 30 minutes could be associated with the loss of its organic component as a consequence of the mineral loss. The R language, software of free availability and virtual consultation, facilitates the integral statistical analysis of quantitative related paired data.