IADR Abstract Archives
Fracture strength of severely damaged premolars restored with short-fibre-reinforced, bulk-fill and nano-hybrid composite core build-ups in the absence or presence of fibre-post
Objectives: This study aims to evaluate the fracture resistance of severely damaged endodontically treated premolars restored with short-fibre-reinforced, bulk-fill and nanohybrid composite core build-ups in the absence/presence posts.
Methods: One-hundred-forty extracted human mandibular premolars were selected for the study. After endodontic treatment, teeth were decoronated at the cemento-enamel junction remaining root length ≥ 12 mm except for control group. The sectioned roots surface area were measured for randomization and the roots were divided into nine groups (n=14) according to preparation type (adhesive, 3-mm intraradicular retention, 8-mm fibre-post preparation) and materyal type (nano-hybrid composite (FiltekTM Z550), bulk-fill flowable (FiltekTM Bulk Fill) and short-fibre-reinforced composite (everX PosteriorTM)). After 5-mm height chamfer crown preparations, metallic crowns were prepared. Following the cementation procedures, specimens were subjected to compressive load at a strain rate of 1 mm/min. Mode of failure was defined as repairable or non-repairable. Pearson correlation analysis was used to determine a correlation between root surface area and fracture strength values. The fracture data were statistically analyzed using two-way ANOVA and Tukey’s test for multiple comparisons.
Results: While there was a moderate correlation in adhesive and 3-mm retentive groups (r=0.61, r=0.53), a weak correlation in 8-mm fibre-post group (r=0.29). The fracture strength was significantly affected by the preparation and the material type (P<0.05). Fibre-post preparation was significantly increased the fracture resistance compared with the others (P<0.05). Short-fibre-reinforced composite had significantly higher fracture resistance values (P<0.05). Groups restored with adhesive and 3-mm retention preparation techniques presented a higher number of repairable fractures.
Conclusions: The restoration of severely damaged premolar teeth with use of a fiber-post with any restorative material increases the fracture strength. Although this in vitro study has limitations regarding clinical relevance, the use of short-fibre-reinforced composite in 3-mm retention preparation offers promising results with several advantages over a fiber-post.
Methods: One-hundred-forty extracted human mandibular premolars were selected for the study. After endodontic treatment, teeth were decoronated at the cemento-enamel junction remaining root length ≥ 12 mm except for control group. The sectioned roots surface area were measured for randomization and the roots were divided into nine groups (n=14) according to preparation type (adhesive, 3-mm intraradicular retention, 8-mm fibre-post preparation) and materyal type (nano-hybrid composite (FiltekTM Z550), bulk-fill flowable (FiltekTM Bulk Fill) and short-fibre-reinforced composite (everX PosteriorTM)). After 5-mm height chamfer crown preparations, metallic crowns were prepared. Following the cementation procedures, specimens were subjected to compressive load at a strain rate of 1 mm/min. Mode of failure was defined as repairable or non-repairable. Pearson correlation analysis was used to determine a correlation between root surface area and fracture strength values. The fracture data were statistically analyzed using two-way ANOVA and Tukey’s test for multiple comparisons.
Results: While there was a moderate correlation in adhesive and 3-mm retentive groups (r=0.61, r=0.53), a weak correlation in 8-mm fibre-post group (r=0.29). The fracture strength was significantly affected by the preparation and the material type (P<0.05). Fibre-post preparation was significantly increased the fracture resistance compared with the others (P<0.05). Short-fibre-reinforced composite had significantly higher fracture resistance values (P<0.05). Groups restored with adhesive and 3-mm retention preparation techniques presented a higher number of repairable fractures.
Conclusions: The restoration of severely damaged premolar teeth with use of a fiber-post with any restorative material increases the fracture strength. Although this in vitro study has limitations regarding clinical relevance, the use of short-fibre-reinforced composite in 3-mm retention preparation offers promising results with several advantages over a fiber-post.