Possible sites for cylinder implants in Swedish individuals aged 20-70 years. A comparative radiological inventory in...

The aim of this study was to evaluate the number of possible sites for cylinder implants in an epidemiological sample of adult individuals and to compare these results with those from a similar inventory performed 10 years earlier. This study, which comprised individuals 20-70 years old, is part of two larger epidemiological dental studies of individuals from the community of Jönköping, Sweden, performed in 1983 and 1993. Random samples of 579 and 575 individuals respectively were examined and classified according to the Eichner index. The radiographic examination included an orthopantomogram and a full-mouth intra-oral examination. Only existing spaces anterior to the second molars were considered as possible implant sites. Cylinder implants with a diameter of 3.75 mm and a length between 7 and 20 mm were plotted on the radiographs.

The most striking result from this study was the reduction by almost a half of the total number of possible implant sites between 1983 and 1993. A certain proportion of existing tooth gaps had been treated with conventional fixed prostheses, usually in small tooth gaps, and this tendency had increased between 1983 and 1993. The need for implants in the anterior frontal region was small but constant (less than 1%) in 1983 and 1993. In the future, implants will be a treatment option in young individuals, most likely in cases of trauma and tooth agenesis. Further it may be assumed that implant treatment in edentulous jaws will continue to increase in relative terms, i.e. the percentage of edentulous jaws that have been treated with implants will increase. In absolute terms, however, the frequency of the treatment will decrease because fewer individuals will be edentulous. Instead, the proportion of partially dentate subjects treated with implants will increase.