Retention of telescopic denture in elderly patients with maximum partially edentulous arch

The telescopic denture is one possible solution for prosthetic rehabilitation for a partially dentate arch with few remaining teeth, which is the reason why it is usually considered in elderly patients. The system of double crowns consists of the male component of attachment or patrix, which is cemented to the abutment tooth, and the female component of attachment or matrix, which is the removable part of the restoration. Retention force represents resistance to those forces which tend to separate the partial denture and supporting tissue in the occlusal direction. Its optimal value is 5-9 N per each patrix and it should strictly be between these limits as a stronger or weaker force will endanger the functionality of the denture or damage the supporting tissue of the abutment teeth.

The goal of this study was to establish the exact value of the individual and total retention force of the completed telescopic system.

The Bredent dynamometer was used for measuring these values. The study involved measuring the individual force of separation of 50 patrix-matrix components, and total force of 20 partial dentures of various designs retained by double crowns made in the Dental Laboratory of the Clinic for Prosthetic Dentistry, Faculty of Stomatology, Belgrade University. The research was carried out in the period from January 2006 to October 2006.

The results showed different values of separation force - from very low values to those exceeding optimal limits. A reduction in the force of separation is necessary in the case of excessive tightness. If there was looseness between patrix and matrix, the cylindrical components of double crowns need to be lined by a suitable composite material.