[Cross sectional study of removable partial denture design in general practitioners].

Many reports have been made on statistical observation on prostheses, among which removable partial denture frequently becomes the subject of investigation from the two sides of cross- and longitudinal- sectional surveys, because its constituent factors are divergent. However, many of such reports used, as subject, the removable partial dentures fitted at clinical practices at the hospitals affiliated to dentistry universities (dentistry departments), and it is hard to say that these reports have grasped the actual circumstances in which removable partial denture is involved since each therapeutic principle as educational hospital constitutes its own specific environment, if the fact that difference occurs in the selecting criteria for each constituent factor according to the operators' designing conception and medical environment is taken into consideration. Then, we have made investigation of edentulous pattern and kinds of denture base material and retainers in 141 cases with removable partial denture fitted at general practitioners, and the following conclusions have been reached. 1. Among the direct retainers of free-end denture, those of clasp with distal rest (Aker's clasp) were the largest in number. 2. By base material, among the direct retainers of free-end denture, many of those of Bar type which has mesial rest (RPI clasp) were observed, in case of metal base, compared with resin base, but difference was observed in the frequency of use of the other retainers. 3. Free-end denture held a majority both in the upper and lower jaws. 4. As base material, resin base was overwhelmingly large in number, compared with metal base.