Restoring teeth to not only offer a beautiful smile but also a highly resistant one is the ultimate goal of the project undertaken by members of the Biomechanics and Ergonomy research group at the Universitat Jaume I (UJI) of Castelló, Spain. To this end, they have concluded that the ideal material for designing posts, which serve to bond the restored piece to the root, is glass fibre. Initially, metallic posts were considered to be more resistant but less aesthetic, according to Ximo Sancho, a member of the Department of Mechanical Engineering and Construction at the UJI.
Contrary to what was commonly believed, glass fibre and other similar materials are much more resistant than metallic materials. Metallic materials had slightly fallen into disuse because, in spite of being considered to be more resistant, teeth blackened owing to the material covering them being transparent. The first phase of the project entitled “Optimising Dental Intraradicular Post Design Through Biomechanical Simulation and Experimental Testing” concludes that, compared with steel, glass fibre supports a greater load, does not require measurements to be as precise when sizing posts and, furthermore, the tooth’s root is not affected in the event of fracture, unlike metallic posts.
Researchers at the UJI are planning to patent a test machine that allows them to study the behaviour of posts under repeated mastication loads. Initially, the studies carried out at the UJI had examined the behaviour of posts by conducting a fracture strength test on them with a universal test machine. The new machine designed at the UJI will have four independently working columns. This will speed up the tests needed to learn the response to a load that is sometimes repeated more than one million times.
The UJI began this research in 2003 having received a proposal from the Department of Stomatology at the University of Valencia. “They didn’t have the capacity or the appropriate means to conduct this kind of tests, so we started a line of collaboration”, Ximo Sancho explains. In this way, a demand for increasing health practitioners’ knowledge on this issue was met because, despite studies being conducted on partial aspects of posts, no study had been done to obtain the ideal post. The design of this ideal post will be covered in a new phase of this project. Once it has been achieved, the post design may be patented, or may be acquired by a manufacturing company as several companies have shown interest in this design. For the time being, the results of the first phase of the project have already been published in scientific circles. This has allowed dental surgeons to know the advantages of glass fibre posts and the conclusions to be incorporated into university teaching.