Evaluation of the push-out bond strength of an adjustable fiberglass post system to an endodontically treated oval root canal

Abstract

To evaluate the push-out bond strength of the adjustable fiberglass post system to dentin. Twenty maxillary canine roots were endodontically treated and divided into two groups (n=10): conventional fiberglass posts (CFPs) and with single adjustable post (SAP) system. Two slices of each third were subjected to the push-out and failure pattern test and the most apical slice was subjected to analysis of the adhesive interface by scanning electron microscopy (SEM). Data were analyzed by the three-way analysis of variance, Tukey, and Friedman tests, and linear regression (α=0.05). The results showed higher push-out bond strength in the initial time interval for SAP (10.3±5.3, p<0.01). After 6 months, there was reduction in push-out bond strength for both (p<0.001). A higher percentage of adhesive and cohesive failures to dentin. After 6 months areas of maladaptation were noted (p=0.000). The SAP is completed to the promissory root canal in relation to alternative CFP.

Influence of bioceramic cones on the quality of root canal filling relative to bond strength and adaptation of the adhesive interface

“…This study was approved by the Research Ethics Committee of the Ribeirão Preto School of Dentistry, University of São Paulo (CAAE: 61010022.8.0000.5419). The sample calculation was made by using the SigmaPlot v.12.00 program (Systat Software, San Jose, CA) based on parameters from previous studies [31][32][33][34]. A probability level of α = 0.05 and a statistical power of 0.9 were considered, with an estimated minimum number of 10 specimens for each group for bond strength tests, failure pattern and analysis of the adhesive interface.…”

“…Ninety-six human maxillary canines with a buccolingual/mesiodistal dimension ≤ 1.5 mm and a root length of 16 mm were used, determined by scanning in a PreXion 3D® cone beam computed tomography scanner (Prexion Co. Ltd, Tokyo, Japan), with an endodontic acquisition protocol of 90 kV, 4 mA, 37 seconds, isotropic voxel of 0.10 mm and eld of view (FOV) of 5x5 mm. Two-dimensional morphometric data of circularity and major and minor diameters were obtained using the OnDemand 3D Project Viewer program (Cybermed Inc., Tustin, CA, USA) to determine the degree of attening of root canals [32][33][34][35][36][37].…”

“…The specimens were explored with a manual type of instrument (Dentsply Maillefer, Ballaigues, Switzerland) until the free extremity of the instrument appeared in the apical foramen. From this measurement, 1.0 mm was subtracted to establish the working length (WL) [32][33][34]37]. Biomechanical preparation was performed with the Wave One Gold Large instrument (45./05) (Wave One Gold, Dentsply Sirona, Ballaigues, Switzerland) in accordance with the manufacturer's recommendation.…”

“…The gutta percha cones with endodontic sealer were introduced up to the WL and the excess lling material at the canal entrance was removed with Paiva-type tampers (Golgran, São Paulo, Brazil), followed by vertical condensation of the lling mass with light pressure in the apical direction for 5 seconds. The canal entrance was temporarily sealed with glass ionomer cement (Ketac Molar EasyMix; 3M, Maplewood, MN, USA) [32][33][34]37].…”

“…Subsequently the teeth were sectioned, obtaining 3 slices of each root third (cervical, middle and apical), with a thickness of approximately 1.0 ± 0.3 mm. The rst and second slices of each third were used for testing extrusion of the root-end lling (push-out test); the third slice was used to assess the quality of the bond interface by scanning electron microscopy (SEM) analysis [32][33][34]37].…”