Experimental studies on clinical use of removable partial dentures with a clasp that is rigidly supported by the abutment were conducted. In order to clarify the effects of denture-wearing, 108 cases of partial denture operation performed on 71 patients were followed up. The partial dentures included dentures with a cone-crown telescope, precision attachments, a conventional clasp, and a clasp rigidly supported by the abutment, as well as overdentures.
The results were as follows:
1. Of the cases examined, 25.7% were dentures with a cone-crown telescope, 31.9% were dentures with a clasp rigidly supported by the abutment, 17.7% were dentures with a conventional clasp, 12.3% were overdentures, and the remaining 12.4% were other types of dentures.
2. Problems were most frequently experienced in patients with 13-16 missing teeth, patients in groups B-1 and B-3 of Eichner's classification, and in patients with 7-8 or 1-2 occlusal contact sites.
3. Patients who wore dentures retained by a cone-crown telescope or conventional clasp experienced more problems than those who wore dentures retained by a clasp that was rigidly supported by the abutment.
