Microhardness and bond strength of resin cements after luting of the conventional and anatomic shaped fiber post

• Grant number: 09/14960-0
• Support Opportunities: Regular Research Grants
• Start date: January 01, 2010
• End date: December 31, 2010
• Field of knowledge: Health Sciences - Dentistry - Dental Materials
• Principal Investigator: Mário Alexandre Coelho Sinhoreti
• Grantee: Mário Alexandre Coelho Sinhoreti
• Host Institution: Faculdade de Odontologia de Piracicaba (FOP). Universidade Estadual de Campinas (UNICAMP). Piracicaba , SP, Brazil

Abstract

Post space of endodontically treated teeth are frequently ovoid. One option is wearing sound teeth and use a higher diameter post, resulting in fragility of root. Another option is use a lesser diameter post and higher cement layer. Relining post with a composite resin enable to achieve lesser cement layer, avoiding sound tooth wearing. However few are known about this technique influence on the mechanical properties of the resin cement and bond strength of the system post/resin/resin cement to root dentin. It will be evaluated the microhardness and bond strength by means of the push out test of chemical and dual cured resin cements used to lute conventional and anatomic shaped posts. Fifty six bovine teeth will have their crowns removed and will be endodontically treated. Roots will be unfilled and enlarged with a diamond point #4137 to obtain standardized post spaces. Half of posts DT Light Post size 3 will be luted on the conventional way and the other half will be relined with composite resin Filtek Supreme CT. After this, one subgroup will be luted with RelyX ARC and the other with Multilink Automix. After 24 hours on a humid environment at 37°C, 10 specimens of each group will be transversally sectioned and submitted to push out test. Another 4 teeth of each group will be longitudinally sectioned and resin cement Knoop microhardness will be evaluated. Results will be submitted to statistical analysis. (AU)