Analysis of elements in the soft tissue covering titanium plates and screws for internal bone fixation by the pixe method

摘要

We made a comparative study of the elements in the periosteum on titanium plates and screws for internal bone fixation, normal periosteum, and oral mucosa by the PIXE method. We studied 11 patients, 4 men and 7 women, with mandibular fracture or facial deformity. The implanted time length of the materials in the body was 5 to 16 months. The analyzed samples were 11 periostea on the materials, 11 normal periostea and 4 oral mucosae. The results were as follows. Twenty four essential and 11 contaminated elements were detected in the periostea on the materials as well as in the normal periostea and the oral nucosae. In the mean values of titanium and aluminum, there were significantly higher values in the periostea on the materials that in the normal periostea. The mean concentration values of the other elements did not differ significantly between that in the periostea on the materials and that in the normal periostea. The concentration of titanium in the periostea on the materials was not correlated with sex, age of the patients, or the implanted time length. However, there was a significantly higher titanium concentration value in the periostea on the plates than on the screws. Our results could indicate that the existence of a titanium element in the periostea on the materials was caused by its dissolution from the materials.