ObjectivesTo compare marginal bone levels, biological, and technical outcomes of screw‐retained versus cemented all‐ceramic implant‐supported zirconia‐based single crowns after an observation period of 7.5 years.MethodsForty‐four single implants in the esthetic zone in 44 patients (22 females, 22 males) were randomly assigned to two types of restorations: SR (screw‐retained); veneered one‐piece zirconia abutment and CR (cement‐retained); veneered lithium disilicate crown intraorally cemented on a one‐piece zirconia abutment. Patients were recalled annually up to 7.5 years and survival rates, biological, and technical parameters assessed.ResultsA total of 31 patients attended the 7.5‐year follow‐up visit (17 SR group, 14 CR group). The survival rate on the restorative level was 77.5% (74.0% CR, 81.0% SR, p = .6399). Median marginal bone loss (MBL) values yielded −0.073 mm (−0.305; 0.238) in the CR and −0.215 mm (−0.500; 0.555) in the SR group (intergroup p = .6194). Mean bleeding on probing (BoP) values were significantly in favor of group SR with 20 ± 17% compared to 40 ± 22% in group CR (p = .011). The overall biological complication rate amounted to 27.5% (42.1% CR, 14.3% SR, p = .0775), whereas the technical complication rate was 32.5% (42.1% CR, 23.8% SR, p = .314). In total, CR restorations showed significantly more complications (84.2% for CR, 38.1% for SR, p = .0041).ConclusionOne‐piece zirconia‐based single crowns on two‐piece dental implants exhibited a high rate of technical and biological complications at 7.5 years of follow‐up. Cemented restorations revealed significant higher rates of bleeding on probing and total complications compared to screw‐retained restorations.

中文翻译：

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一项为期 7.5 年的随机对照临床研究，比较了骨水泥和螺钉固位一体式氧化锆基种植体支持的单冠


目的 在 7.5 年的观察期后，比较螺钉固位与骨水泥全瓷种植体支持的氧化锆基单冠的边缘骨水平、生物学和技术结果。 方法 44 名患者的审美区有 44 个单种植体（22女性，22 名男性）被随机分配到两种类型的修复体：SR（螺钉固位）；贴面一体式氧化锆基台和 CR（骨水泥固位）；口腔内粘合在一体式氧化锆基台上的贴面二硅酸锂冠。每年回顾一次患者，直至 7.5 年，并对生存率、生物学和技术参数进行评估。 结果 共有 31 名患者参加了 7.5 年的随访（17 名 SR 组，14 名 CR 组）。恢复水平的存活率为 77.5%（74.0% CR、81.0% SR、 p =.6399）。 CR 组的中位边缘骨丢失 (MBL) 值为 -0.073 mm (-0.305; 0.238)，SR 组的中位边缘骨丢失 (MBL) 值为 -0.215 mm (-0.500; 0.555)（组间） p =.6194）。探诊平均出血 (BoP) 值明显有利于 SR 组，为 20 ± 17%，而 CR 组为 40 ± 22%（ p =.011）。总体生物并发症发生率为 27.5%（CR 42.1%，SR 14.3%， p = .0775），而技术并发症发生率为 32.5%（CR 42.1%，SR 23.8%， p =.314）。总的来说，CR 修复体的并发症明显增多（CR 为 84.2%，SR 为 38.1%， p = .0041). 结论 在 7.5 年的随访中，两片式牙种植体上的单片式氧化锆基单冠表现出很高的技术和生物学并发症发生率。 与螺钉固位修复体相比，骨水泥修复体的探诊出血率和总并发症率明显更高。