Restoration Of Pulpless Tooth With Micro Fiber-Posts:a SEM Study

Objectives: Restoration of pulpless tooth using a material inserted in plastic phase in case of major decay appears to be the best solution to retain a maximum of residual dental tissue.
A new restoration concept, using fibro-structured and fasciculated micro-posts, provides a new alternative to current reconstructions techniques. Micro-posts are made of composite and silica fibers and their flexibility allows them to adapt to all root morphologies.
The aim of this study was to experiment the interfaces between micro-posts, bonding composite and dentinal walls.

Methods: Fifteen teeth extracted for orthodontic or periodontal reasons were endodontically treated and restored with micro-posts, adhesive and composite. The samples were coated, sectioned, metallized, polished to be observed with SEM.
For all samples, one cut was made 1 mm below the root-to-root limit and another was made 3 mm under the first cut in the apical direction.
SEM observations were made at several magnifications: from X 35 to X 750, with a voltage of 30 kV.

Results: Scanning electron microscope sections show that the distribution of micro-posts in the canal is random. Chemical and mechanical bond between the micro-posts and the sealing composite is perfect even without adhesive application. The bond between the composite and the root walls shows some debonding spaces, which may be due to the manipulation or more likely to the polymerization contraction of the resin.

Conclusions: Easy to implement clinically, this new concept allows anatomical retention of micro-posts, which is less invasive than with a single standardized post.