title: Relined fiberglass post: an ex vivo study of the resin cement thickness and dentin-resin interface.
abstract: The aim of this study was to evaluate the thickness of resin cements in the root thirds when using conventional fiberglass posts (CP) and relined fiberglass posts (RP) in weakened roots and to evaluate the morphological characteristics of the dentin-resin interface. Forty human maxillary anterior teeth had the crown sectioned below the cemento-enamel junction. The canals were endodontically treated and weakened with diamond burs. Teeth were divided into four groups (n = 10): Group 1 - CP + RelyX ARC; Group 2 - CP + RelyX U200; Group 3 - RP + RelyX ARC; and Group 4 - RP + RelyX U200. Prior to luting, 0.1% Fluorescein and 0.1% Rhodamine B dyes were added to an adhesive and resin cement, respectively. Slices were obtained from the apical, middle, and cervical thirds of the root. Confocal laser scanning microscopy images were recorded in four areas (buccal, lingual, mesial, distal) of each third. In each area, four equidistant measures of the resin cement were made and the mean value was calculated. The interface morphology was observed. The data were submitted to three-way ANOVA and Tukey's test (α = 0.05). The interaction between fiberglass posts, resin cement, and root thirds was significant (p < 0.0001). The resin cement thicknesses were significantly lower for RP in comparison with CP, except in the apical third. There was no significant difference between the resin cements for RP. There was formation of resin cement tags and adhesive tags along the root for RP. RP favored the formation of thin and uniform resin cement films and resin tags in weakened roots.
authors.affiliation: Pontifícia Universidade Católica do Rio Grande do Sul - PUC-RS, School of Dentistry, Department of Restorative Dentistry, Porto Alegre, RS, Brazil.
authors.forename: Niélli Caetano de
authors.initials: NC
authors.lastname: Souza
authors.affiliation: Pontifícia Universidade Católica do Rio Grande do Sul - PUC-RS, School of Dentistry, Department of Restorative Dentistry, Porto Alegre, RS, Brazil.
authors.forename: Maurem Leitão
authors.initials: ML
authors.lastname: Marcondes
authors.affiliation: Pontifícia Universidade Católica do Rio Grande do Sul - PUC-RS, Institute of Biomedical Research, Porto Alegre, RS, Brazil.
authors.forename: Ricardo Vaz
authors.initials: RV
authors.lastname: Breda
authors.affiliation: Pontifícia Universidade Católica do Rio Grande do Sul - PUC-RS, School of Dentistry, Department of Restorative Dentistry, Porto Alegre, RS, Brazil.
authors.forename: João Batista Blessmann
authors.initials: JB
authors.lastname: Weber
authors.affiliation: Pontifícia Universidade Católica do Rio Grande do Sul - PUC-RS, School of Dentistry, Department of Restorative Dentistry, Porto Alegre, RS, Brazil.
authors.forename: Eduardo Gonçalves
authors.initials: EG
authors.lastname: Mota
authors.affiliation: Pontifícia Universidade Católica do Rio Grande do Sul - PUC-RS, School of Dentistry, Department of Restorative Dentistry, Porto Alegre, RS, Brazil.
authors.forename: Ana Maria
authors.initials: AM
authors.lastname: Spohr
mesh_terms: D000704:Analysis of Variance; D017438:Bisphenol A-Glycidyl Methacrylate / Q000737:chemistry*; D001840:Dental Bonding / Q000379:methods; D003786:Dental Pulp Cavity / Q000187:drug effects; D003804:Dentin / Q000187:drug effects*; D017220:Dentin-Bonding Agents / Q000737:chemistry; D005898:Glass / Q000737:chemistry*; D006801:Humans; D008422:Materials Testing; D018613:Microscopy, Confocal; D011092:Polyethylene Glycols / Q000737:chemistry*; D011109:Polymethacrylic Acids / Q000737:chemistry*; D011176:Post and Core Technique; D015203:Reproducibility of Results; D019279:Resin Cements / Q000737:chemistry*; D013997:Time Factors; D014092:Tooth Root / Q000187:drug effects
chemical_list: D017220:Dentin-Bonding Agents; D011109:Polymethacrylic Acids; C462240:RelyX ARC; C587242:RelyX U200; D019279:Resin Cements; C009753:fiberglass; D011092:Polyethylene Glycols; D017438:Bisphenol A-Glycidyl Methacrylate