[Removable prostheses with controlled distribution of forces on endosseous implants]

The differentiated behaviour of dental abutments and alveolar mucosal tissues following functional loading has always created design problems in the field of removable partial prostheses. This situation of disequilibrium is particularly clear when natural piers are replaced by osteointegrated implants which are by definition unable to adapt to the masticatory load. In order to avoid this different behaviour, the authors feel it is advisable to use a removable partial prosthesis fitted with telescopic retention, defined as 'controlled distribution of the forces', which can transfer the functional masticatory load to the osteointegrated implants and alveolar mucosal structures in a harmonious, balanced and homogeneous manner. The authors give a detailed description of the structure and working of this particular type of prosthesis, highlighting its advantages, namely: 1) controlled distribution of occlusal forces to osteointegrated implants and alveolar osteomucosal structures; 2) reduced number of implants required (2 are sufficient); 3) stability of prosthesis comparable to a fixed structure; 4) possibility of removing the latter with the advantage of maintaining oral hygiene around implants; 5) reduced size of prosthesis. Given that this type of prosthesis has been designed, realized and fitted to natural piers, with optimal clinical results, by the Dental Implant Department of the Dentistry Clinic of Turin University since 1969, the authors affirm that this prosthetic structure is particularly suitable in cases of edentulism with advanced maxillary atrophy.