Clinical evaluation of the ceramic on zirconium crouns and bridges in and on implants: results after 4 years

Abstract

Introduction: Zirconium as a dental material generated special interest for dentistry, being used on a large scale for fixed dentures because of its special properties: chemical and dimensional stability, high mechanical resistance, its Young module (210 Gpa) is compatible with that of steel alloys (193 Gpa). Our studies are focused on the resistance and reliability of zirconium blunts on implants, especially of the individual ones, but also the type of ceramics used for dental bridges. We made ceramic - zirconium crouns and bridges for 89 patients (56 women, 33 men), aged between 15 and 57 years, for a period of 4 years. The method used in the lab was the CAD-CAM system, then scanning with a Dental Wings scanner and later milling bye CAM system from Wieland. The ceramic used was from 3 different manufacturers: Wieland (ZenoTec), Vita(VM9) and IVOCLAR (Emax)- and also different labs. During the follow-up period we noticed that the physiognomic component was chipped, especially in the ZonaTec bridges, and that the frame of the bridges was fractured on the pontic.