Fracture resistance of endodontically treated maxillary central incisors with varying ferrule heights and configurations: In vitro study

OBJECTIVE: The objective of this study is to determine the best ferrule configuration of endodontically treated teeth. MATERIALS AND METHODS: A total of 40 freshly extracted maxillary central incisors were collected. Teeth were allocated into following four groups of each having 10 teeth. Group 1 teeth restored with crowns (CRN), Group 2 endodontically treated teeth restored with crowns (RCT and CRN), Group 3 endodontically treated teeth restored with cast dowel cores and crowns incorporating uniform 2 mm ferrule (2 FRL), Group 4 endodontically treated teeth restored with cast dowel cores and crowns incorporating uniform 1 mm ferrule (1 FRL). Crown preparation was performed with varying ferrule heights, crowns were cemented with resin modified glass ionomer cement and were kept in 100% humidity for 3 days, all specimens were loaded to failure in a universal testing machine at 0.5 mm/min. Results were obtained in the form of kilo Newton and Newton. RESULT: The statistical analysis applied was an analysis of variance to detect the presence of group differences. Pair wise comparisons between the groups were analyzed with the Tukey Kramer significant difference test for multiple comparisons. CONCLUSION: Ferrule had a significant role in the fracture resistance of custom cast post core restored teeth. Endodontically treated maxillary central incisors with a uniform 2 mm ferrule were more fracture resistant than those with a uniform 1 mm ferrule.