Restoration of Endodontically Treated Teeth with Carbon Fibre Posts — A Prospective Study

Décembre 2000, Vol. 66, No 11 613 There is no consensus on the best procedure for restoring endodontically treated teeth. However, retrospective studies1-6 do identify factors that affect the success rate. Tooth location in the arch,1-3 type of occlusion,2 amount of remaining dentin3 and type of abutment1 affect the selection of a restorative approach that will produce a favourable outcome. Yet in spite of this evidence, a recent survey7 calls into question dentists’ patterns of restoring endodontically treated teeth in the United States. Failure rates averaging 2% per year have been reported2-6 for both single crowns and retainers for fixed partial dentures. The 1992 Hatzikyriakos1 study reported dramatic differences in failure rate over 3 years between complete coverage restorations functioning as single crowns (5.5%) and those functioning as fixed partial denture abutments (16.4%). The reported causes of failure were debonding, post fracture, caries and root fracture. Because of the excellent adhesion of dentinal bonding agents to tooth structure, when used with resin core build-ups or in conjunction with luting cements, the threat of fracture as the chief failure mode in endodontically treated teeth is increasing.8 Corrosion caused by dissimilar metals, area variation and stress, first reported in 19709 is just now being implicated as a source of fracture potential in post-endodontic restorations.10 In addition to established factors, the composition of the post system may play a pivotal role in restorative success. To address this concern, a carbon fibre post system was introduced in Europe in 1990. A carbon-epoxy composite post was reinforced with long carbon unidirectional, high-performance fibres stretched parallel to the axis of the post.11 The fibres represented 64% of the structural volume and the matrix, which bound the fibres together, was an epoxy resin. King and Setchell12 showed that prefabricated carbon fibre posts exhibit properties comparable with, and in some cases better than, those of prefabricated metal posts, and McDonald and Restoration of Endodontically Treated Teeth with Carbon Fibre Posts — A Prospective Study