[Use of light-curing composite and adhesive systems for the cementation of tranlucent fiber posts. SEM analysis and pull-out test]. / Utilizzo di adesivi e compositi fotopolimerizzanti nella cementazione di perni translucenti: analisi al SEM e Pull-out test.

ABSTRACT

AIM: The purpose of this study was to compare 2 different techniques for the cementation of translucent fiber posts. The comparison was carried out by means of tensile bond strength testing and SEM evaluation of the interfaces morphology post/cement and cement/dentin. METHODS: Twenty upper central extracted incisors were first endodontically treated and then randomly divided into 2 groups of 10 samples each. Twenty translucent Endo Light-posts (RTD) were cemented following 2 different METHODS: In Group 1 Excite (Ivoclar Vivadent) and Tetric Flow (Ivoclar Vivadent) were applied and light-cured. In Group 2 All Bond 2 (Bisco) and RelyX ARC (3M) were applied, light-cured and then self-cured. A tensile bond strength test was carried out on 14 roots, 7 from each group. Subsequently, 2 roots were cut lengthwise and observed using a SEM. The remaining 6 roots (3 from each group) were cut into 5 transversal sections and observed using a SEM. The tensile force required to dislodge the cemented posts from the 7 roots of each group was recorded by means of a testing machine. RESULTS: Group 1 revealed a bonding strength which was slightly inferior to the bonding strength registered in Group 2. SEM evaluation showed a good quality of bond. Without taking into account the curing method used, the polymerization carried out by means of light curing seems to result in a better adaptation of cement. CONCLUSIONS: Self curing cement still represents the most reliable alternative, even if photo-curing cement might guarantee a most efficient stress distribution along the walls of the canal.