COMPORTAMENTO DE DOIS DIFERENTES RETENTORES INTRARRADICULARES COM DIFERENTES ESTRATÉGIAS DE UNIÃO

Resumo (EN)

Objective: The aim of this study was to evaluate the adhesive interface and mode of
failure of endodontically treated bovine incisors restored with anatomized glass fiber
posts and CAD/CAM posts using different bonding strategies. Methods: 60 bovine
incisor root canals were endodontically treated, uncovered and prepared for the
preparation of the posts and standardized at 10 mm in length for the retainer. The teeth
were randomly divided into four groups: (G1) Anatomized fiberglass cemented with
Dual Self-Adhesive Resin Cement (control group); (G2) Anatomized posts cemented
with Universal Cement; (G3) Milled fiberglass composite cemented with Dual Cement;
(G4) Milled fiberglass composite cemented with Universal Cement. After cementing
the posts and storing them for 7 days at 37oC, each sample was cut into 3 2mm slices
from each third (coronal, middle and apical). The thirds were subjected to the Push
Out mechanical test on a universal testing machine at a speed of 0.5 mm/min until
failure. The post-cementation interfaces and failure modes were evaluated and
classified using scanning electron microscopy (SEM). The data obtained was

subjected to the ANOVA test for repeated measures and normality by Kolmogorov-
Smirnov, Bartley's test for homogeneity of variance of the thirds and Maurchly's

sphericity test for the repeated measure factor. Statistical differences were found
between the post types, with the milled groups being similar to each other and with
higher bond values than the anatomized posts, which were also similar to each other.
There was no statistical difference between the thirds and in relation to the cementation
strategy used. As for the types of failure, for the anatomized glass fiber groups,
displacement of the post and adhesive failure at the post/composite resin interface
were the most recurrent. For the milled composite groups, the most recurrent type of
failure was cohesive failure in dentin.