Influence of surface remodelling using burs on the macro and micro surface morphology of anatomically formed fibre...

To evaluate the effect of modifying preformed fibre-reinforced composite (FRC) endodontic posts on their surface morphology and to determine how this procedure affects the integrity of the posts.

Surfaces of 10 preformed glass-fibre posts (group 1) and carbon-fibre posts (group 2) were compared with those of individually formed glass-fibre posts (group 3). Ten FRC posts were modelled in order to give them a shape as close as possible to the anatomy of oval root canals. Starting from a preformed cylindrical fibre post 2.5 mm in diameter, it was modelled in such a way as to passively occupy the entire post-space length, using a cast previously created as a guide. Microscopic analyses (optical stereomicroscope and scanning electron microscope) of the post surfaces revealed similar features in all three groups. All posts had regular surfaces after cutting with a diamond bur. Smear layer mainly attributable to the cutting procedures covered the cut surface of some specimens. In conclusion, modulation of a fibre post using a diamond-coated bur did not show a loss of integrity of the post. *Because of the importance of micromechanical retention, the surface integrity of fibre posts may be important for adhesion between post and composite resin. *Modification of a fibre post using a diamond-coated bur did not damage the surface integrity of the posts. *Fibre posts can be ground to a different shape without losing their surface integrity, resulting in posts with a surface that is not visibly different from unmodified commercially available fibre posts.