Push-out bond strength of fiber posts to root dentin using glass ionomer and resin modified glass ionomer cements

• Main Authors: Jefferson Ricardo PEREIRA, Ricardo Abreu da ROSA, Marcus Vinícius Reis SÓ, Daniele AFONSO, Milton Carlos KUGA, Heitor Marques HONÓRIO, Accácio Lins do VALLE, Hugo Alberto VIDOTTI
• Format: Article
• Language: English
• Published: University of São Paulo 2014-10-01
• Series: Journal of Applied Oral Science
• Subjects: Endodontics; Post and core technique; Dental cements; Glass ionomer cements; Shear strength
• Online Access: http://www.scielo.br/scielo.php?script=sci_arttext&pid=S1678-77572014000500390&lng=en&tlng=en

OBJECTIVE: The purpose of this study was to assess the push-out bond strength of glass fiber posts to root dentin after cementation with glass ionomer (GICs) and resinmodified glass ionomer cements (RMGICs). MATERIAL AND METHODS: Fifty human maxillary canines were transversally sectioned at 15 mm from the apex. Canals were prepared with a step back technique until the application of a #55 K-file and filled. Post spaces were prepared and specimens were divided into five groups according to the cement used for post cementation: Luting & Lining Cement; Fuji II LC Improved; RelyX Luting; Ketac Cem; and Ionoseal. After cementation of the glass fiber posts, all roots were stored at 100% humidity until testing. For push-out test, 1-mm thick slices were produced. The push-out test was performed in a universal testing machine at a crosshead speed of 0.5 mm/minute and the values (MPa) were analyzed by Kolmogorov-Smirnov and Levene's tests and by two-way ANOVA and Tukey's post hoc test at a significance level of 5%. RESULTS: Fiber posts cemented using Luting & Lining Cement, Fuji II LC Improved, and Ketac Cem presented the highest bond strength to root dentin, followed by RelyX Luting. Ionoseal presented the lowest bond strength values (P>0.05). The post level did not influence the bond strength of fiber posts to root dentin (P=0.148). The major cause of failure was cohesive at the cement for all GICs and RMGICs. CONCLUSIONS: Except for Ionoseal, all cements provided satisfactory bond strength values.