Methods: Patients needing posterior crowns and meeting inclusing criteria were recruited following UNC-Chapel Hill IRB approval, enrolled and signed informed consent documents. Teeth were prepared for single unit posterior crowns, temporized, and permanent all-ceramic crowns placed using conventional prosthetic techniques. Teeth were etched, adhesive bonding agent placed, and all crowns cemented with composite resin cement. Clinical and radiographic parameters for crown and margin integrity, pulpal status, occlusion and presence/absence of pulpal symptoms were conducted pre-treatment, and at baseline (crown cementation), 12, 36 and 60 month recall visits. PA and bitewing films were taken at the same intervals. A similar number on non-restored contralaterial or adjacent teeth served as controls, and were similarly assessed.
Results: A total of 41 posterior crowns were placed and evaluated at baseline. At 60 months, 35 crowns remained in service for assessment. The survival of all ceramic crowns was 97.5% at 60 months. There were no significant differences in any prosthodontics, periodontal, pulpal or radiographic, measure between baseline and 60 months. There was no difference found in pulpal response rate of restored and controll teeth. The overall pulpal complication rate at 60 months was 7.3% (0.0% for controls), which meets existing published guidelines for full-coverage crown materials.
Conclusions: Eris/Empress 2 all-ceramic crowns adhesively bonded to posterior teeth exhibited minimal post-operative prosthetic, periodontal, radiographic or pulpal complications between baseline and 60 months. This all-ceramic crown / cement combination appears acceptable for use on posterior teeth requiring full coverage restorations.
Keywords: Ceramics, Clinical trials, Human and Prosthodontics