Department of Buccofacial Prostheses Faculty of Odontology, University Complutense, Madrid, Spain.
J Prosthet Dent. 2012 Jun;107(6):373-9. doi: 10.1016/S0022-3913(12)60094-8.
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.
The purpose of this randomized prospective study was to evaluate the clinical performance of zirconia (Lava) 3-unit posterior fixed dental prostheses.
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).
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.
The results of a 3-year evaluation suggest that posterior zirconia 3-unit fixed dental prostheses are a reliable treatment.
近年来，氧化锆基陶瓷具有良好的机械性能，这增加了人们对在后牙区使用固定义齿的接受程度，但能证明这些修复体长期效果的临床研究却很少。此外，在更广泛地应用这种材料之前，还必须解决某些并发症。
本随机前瞻性研究的目的是评估氧化锆（Lava）三单位后牙固定义齿的临床性能。
将 20 个三单位固定义齿放置在 17 名患者中，以替代第二前磨牙或第一磨牙。11 个位于上颌，9 个位于下颌。所有基牙均采用 0.8 至 1mm 的肩台预备，并用 Lava 系统制备基底。修复体用树脂水门汀黏固。由 2 名经过校准的检查者使用加利福尼亚牙科协会质量评估系统，分别在 1 周（基线）和放置后 1、2、3 年对固定义齿进行独立评估。评估牙周参数：牙龈指数、菌斑指数、边缘指数，以及基牙和对侧牙的探诊深度。采用描述性统计和 Wilcoxon 符号秩检验（α=.05）进行数据分析。
所有固定义齿在 3 年后均被评为满意，在观察期间未观察到基底的骨折。在 3 年检查时，有 1 个固定义齿因生物并发症而丢失，有 2 名患者观察到饰面陶瓷有轻微的崩瓷。除了边缘指数外，试验牙和对照牙的牙周参数无显著差异。
3 年评估的结果表明，后牙氧化锆三单位固定义齿是一种可靠的治疗方法。
