Use of Zircalloy to induce bone regeneration. A 2-year follow-up study

In a previous study we analyzed the behaviour of Zircalloy 4 particles employed in patients with significant loss of periodontal bone support which threatened the permanence in situ of the tooth. We herein present the results obtained after regular examination over a 2-year period of 6 patients submitted to this treatment. Our results reveal that all patients exhibited excellent gingivo-periodontal health with an increase in clinical insertion of 7 mm +/- 1 and a marked reduction in motility from 3 to 1. None of the cases featured added inflammation or expulsion of the implant material. In one of the cases it was possible to study the histology of the area by punch biopsy with a disposable needle (Sherwood-Medical). Analysis of the sample revealed the presence of bone tissue in intimate contact with implanted metallic particles of Zircalloy 4, producing osseointegration. This osseointegration would lead to filling of the periodontal bone defect. Macrophages loaded with metallic particles were found in the vicinity of particles which were not osseointegrated. These features may correspond to superficial areas related with soft tissue as observed in our study on alveolar filling in rats with the same type of particles.