A prospective evaluation of zirconia posterior fixed dental prostheses: three-year clinical results.
BACKGROUND
Although the favorable mechanical properties of zirconium oxide-based ceramics have increased the acceptance of fixed dental prostheses for use in the posterior regions of the mouth in recent years, there are few clinical studies documenting the longevity of these restorations. Furthermore, certain complications must be resolved before the material is used more extensively.


OBJECTIVE
The purpose of this randomized prospective study was to evaluate the clinical performance of zirconia (Lava) 3-unit posterior fixed dental prostheses.


METHODS
Twenty 3-unit fixed dental prostheses were placed in 17 participants to replace a second premolar or a first molar. Eleven were placed in the maxilla and 9 in the mandible. All abutment teeth were prepared with a chamfer finish line of 0.8 to 1 mm, and frameworks were prepared with the Lava system. Restorations were cemented with a resin cement. Two calibrated examiners independently evaluated the fixed dental prostheses 1 week (baseline) and 1, 2, and 3 years after placement with the California Dental Association quality evaluation system. The periodontal parameters: the gingival index, plaque index, margin index, and the probing depths of abutment teeth and contralateral teeth were assessed. Data were analyzed by using descriptive statistics and the Wilcoxon signed-rank test (α=.05).


RESULTS
All fixed dental prostheses were rated satisfactory after 3 years, and no fracture of the framework was observed during the observation period. One fixed dental prostheses was lost because of a biological complication at the 3-year examination, and a small degree of chipping of the veneering ceramic was observed in 2 participants. No significant differences among the periodontal parameters of the test and control teeth were observed except for the margin index.


CONCLUSIONS
The results of a 3-year evaluation suggest that posterior zirconia 3-unit fixed dental prostheses are a reliable treatment.
Department of Buccofacial Prostheses Faculty of Odontology, University Complutense, Madrid, Spain.
Jesus
J
Peláez
Pablo G
PG
Cogolludo
Benjamin
B
Serrano
Jose F L
JF
Lozano
Maria J
MJ
Suárez
D000328:Adult; D000368:Aged; D002484:Cementation / Q000379:methods; D000044:Dental Abutments; D018772:Dental Marginal Adaptation; D003764:Dental Materials / Q000737:chemistry*; D003774:Dental Plaque Index; D003776:Dental Porcelain / Q000737:chemistry; D019232:Dental Restoration Failure; D003801:Dental Veneers; D003779:Denture Design; D003830:Denture, Partial, Fixed; D004955:Esthetics, Dental; D005260:Female; D005500:Follow-Up Studies; D006801:Humans; D008297:Male; D008875:Middle Aged; D010512:Periodontal Index; D010514:Periodontal Pocket / Q000145:classification; D011446:Prospective Studies; D019279:Resin Cements / Q000737:chemistry; D016019:Survival Analysis; D019231:Tooth Preparation, Prosthodontic; D016896:Treatment Outcome; D055815:Young Adult; D015040:Zirconium / Q000737:chemistry*
D003764:Dental Materials; D019279:Resin Cements; D003776:Dental Porcelain; D015040:Zirconium; C028541:zirconium oxide