Evaluation of the bond-strenght of a niobium phosphate bioactive based composite and gutta-percha on account of an endodontic sealer

• Grant number: 16/10105-2
• Support type: Scholarships in Brazil - Scientific Initiation
• Effective date (Start): August 01, 2016
• Effective date (End): July 31, 2017
• Field of knowledge: Health Sciences - Dentistry - Endodontics
• Principal Investigator: Giulio Gavini
• Grantee: Marina Silva Cappellano
• Home Institution: Faculdade de Odontologia (FO). Universidade de São Paulo (USP). São Paulo , SP, Brazil

Abstract

The obturation step of the endodontic treatment is critical, since a correct seal and impearmeabilization of the endodotic space are crucial for clinical success. Very promising materials for this application are the bioactive glasses and bioceramic sealers: besides having the ideal standards like radiopacity, antimicrobial activity and dimensional stability, they also have the ability to release ions and a great adhesion to the root canal wall due to its capability of hydroxyapatite formation. The aim of this study is to evaluate the bond strength of gutta-percha cones associated with vitreous particles of niobiumphosphate among the endodontic sealers, through the µpush-out test. 45 distal roots of inferior molars will be used, extracted for various reasons. The teeth will be prepared and instrumented: determination of the real work length by the direct view technique, evacuation of the canal with K files number 15 in the presence of sodium hypochlorite 1%, instrumentation with the reciprocanting system R50 and irrigation with 10ml of sodium hypochlorite 1% and EDTA 17% each, followed by aspiration with a decreasing diameters cannula. Then, the teeth will be divided in three groups: group CB, composed by teeth obturated only with the bioactive guta-percha; group CBAH, teeth obturated with bioactive guta-percha and AH Plus sealer and group CBBC, composed by obturations with bioactive guta-percha and the bioceramic sealer EndoSequence BC Sealer. The teeth will be divided randomly and obturated according to their group with the continuous wave condensation thermoplastic technique. The roots will be sectioned into 4mm tick discs and then submitted to the µpush-out test. After the assay, the discs will be also evaluated in a estereomicroscopical magnifying glass for analysis of the failure mode.