CLINICS 2011;66(12):2063-2070 Clinical performance of zirconia crowns Tartaglia GM et al. Table 3 - Clinical evaluation of the analyzed single-crown zirconia prostheses, according to Hickel et al.22 at the three- year follow-up examination. All values represent the number (and percentage) of prostheses. Clinical evaluation single crowns Aesthetic properties Surface luster Surface staining Color stability and translucency Anatomic form Functional properties Fractures and retention Marginal adaptation Contact point/food impact Radiographic examination Patient’s view Biological properties Postoperative (hyper-) sensitivity* Recurrence of caries, erosion, abfraction Periodontal response Adjacent mucosa Oral and general health Position Anterior Posterior Anterior Posterior Anterior Posterior Anterior Posterior Anterior Posterior Anterior Posterior Anterior Posterior Anterior Posterior Anterior Posterior Anterior Posterior Anterior Posterior Anterior Posterior Anterior Posterior Anterior Posterior Support Implants Teeth Implants Teeth Implants Teeth Implants Teeth Implants Teeth Implants Teeth Implants Teeth Implants Teeth Implants Teeth Implants Teeth Implants Teeth Implants Teeth Implants Teeth Implants Teeth Implants Teeth Implants Teeth Implants Teeth Implants Teeth Implants Teeth Implants Teeth Implants Teeth Implants Teeth Implants Teeth Implants Teeth Implants Teeth Implants Teeth Implants Teeth Implants Teeth 2067 A 0 0 0 0 5 (100) 39 (100) 31 (100) 145 (100) 0 0 0 0 0 0 0 0 5 (100) 39 (100) 31 (100) 142 (98) 5 (100) 39 (100) 31 (100) 145 (100) 5 (100) 39 (100) 31 (100) 138 (95) 5 (100) 39 (100) 31 (100) 145 (100) 5 (100) 31 (79) 9 (29) 61 (40) 5 (100) 39 (100) 31 (100) 145 (100) 5 (100) 39 (100) 31 (100) 145 (100) 0 0 0 0 5 (100) 39 (100) 0 7 (5) 5 (100) 39 (100) 31 (100) 145 (100) B 5 (100) 39 (100) 31 (100) 145 (100) 0 0 0 0 5 (100) 39 (100) 31 (100) 145 (100) 5 (100) 39 (100) 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 8 (21) 22 (71) 84 (60) 0 0 0 0 0 0 0 0 5 (100) 39 (100) 29 (94) 97 (67) 0 0 30 (97) 98 (67) 0 0 0 0 C 0 0 0 0 0 0 0 0 0 0 0 0 0 0 31 (100) 145 (100) 0 0 0 0 0 0 0 0 0 0 0 7 (5) 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 2 (6) 48 (33) 0 0 1 (3) 40 (28) 0 0 0 0 0 0 0 3 (2) 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 D 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 E 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 Anterior: incisors, canines; Posterior: premolars, molars. A: clinically excellent/very good; B: clinically good; C: clinically sufficient/satisfactory; D: clinically unsatisfactory; E: clinically poor. *All the teeth were endodontically treated. For implants, we evaluated loss of osseointegration. greater number of units were more fragile than the single crowns. Fractures were found only in prostheses with more than three units and were located at the interdental connectors or in the zirconia core adjacent to the connectors, in accordance with published findings.2,7 Nevertheless, these 11 crowns represented only 9% of the total multiple- unit (four to six) crowns, which indicated that multiple-unit zirconia core prostheses demonstrated greater clinical