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Resin cement thickness in oval-shaped canals: oval vs. circular fiber posts in combination with different tips/drills
Ivanovic Coniglio1, Franklin Garcia-Godoy, Elisa Magni
1Department of Fixed Prosthodontics and Dental Materials, School of Dental Medicine, University of Siena, Italy.
Purpose:
To evaluate the cement thickness around oval and circular posts luted in oval post spaces prepared with different drills/tips.
Methods:
Extracted premolars were endodontically treated and obturated, then randomly divided into three groups (n = 5) according to the tips/drills used for post-space preparation and to the type of fiber post luted: medium grit oval tip + oval posts, fine grit oval tip + oval posts, Mtwo Post File drill + circular posts. The specimens were sectioned in horizontal slices; one slice per canal third was chosen for each post-space, resulting in three slices for each specimen. The distances between the canal wall and the post perimeter were measured on SEM images of each slice.
Results:
The fine grit tip + oval post group obtained statistically significant lower cement thicknesses than the other groups (P < 0.05), in particular in the apical third. The MtwoPF + circular post group showed the highest cement thickness, comparable to that of the medium tip + oval post group. A good post fitting in oval-shaped canals can be obtained using a fine grit oval tip combined with oval posts.
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