A RETROSPECTIVE STUDY OF COMBINED FIXED-REMOVABLE RECONSTRUCTIONS WITH THEIR ANALYSIS OF FAILURES

The survival rate and the reasons for failures of 130 combined fixed-r emovable reconstructions (CFR), incorporated in 112 patients, were ass essed. Each CPR reconstruction was classified depending on its attachm ents: 76 reconstructions were attached with rigid, precise attachments , and constituted the rigid group; 54 reconstructions were attached wi th either semi-precision or individual attachments and were defined as the semi-rigid group. Of the 130 reconstructions, 41 were determined as complete successes, 39 as partial successes and 50 as failures, lea ding to 37 major repairs and to 13 new reconstructions. Three reconstr uctions failed due to technical reasons, 36 due to biological reasons and for 11 reconstructions, both categories of reasons were responsibl e for their failure. In total, technical reasons were counted 15 times in comparison to 73 biological reasons for those 50 failed reconstruc tion, with 29 fractured abutment teeth as the most common biological r eason. Within the rigid group, 45 failed reconstructions were observed , whereas within the semi rigid group only 5 failures occurred, leadin g to an 8-year survival estimate (+/- so) of 30.1% (+/- 6.9%) for the rigid group and 93.1% (+/- 3.9%) for the semi rigid group. Beside the attachment type, the anatomy of the partially edentulous tooth arch in form of the free-end situation and the dentate opposing jaw were iden tified as risk factors.