Department of Fixed and Removable Prosthodontics, Dental School, University Medical Center Groningen, University of Groningen, Groningen, The Netherlands.
J Clin Periodontol. 2013 Mar;40(3):303-10. doi: 10.1111/jcpe.12051. Epub 2013 Jan 16.
Comparing treatment outcome of four and six bar-connected implants in the anterior maxillary region to support an overdenture during a 1-year follow-up period.
Fifty edentulous patients with lack of retention and stability of the upper denture, but with sufficient bone volume to place implants in the anterior maxillary region, were selected. Randomization assigned patients to either four or six implants. Implant survival, overdenture survival, clinical scores, radiographic bone height changes, and patients' satisfaction were assessed.
Forty-nine patients (one drop out) completed the 1-year follow-up. After 1 year, implant survival was 100% in the four implants group and 99.3% in the six implants group (one implant lost). Overdenture survival was 100% in both groups. Mean clinical scores were low and did not differ between groups (independent Student's t-test). Mean marginal bone resorption was 0.24 ± 0.32 mm in the four implants group and 0.25 ± 0.29 mm in the six implants group. Patients' satisfaction had improved in both groups (paired Student's t-test).
Bar-supported overdentures on four implants in the anterior maxillary region are not inferior to overdentures supported by six bar-connected implants. Implant survival was high, peri-implant conditions were healthy and patients' satisfaction had increased significantly in both groups.
比较在前上颌区域使用四个和六个杆连接种植体来支持覆盖义齿的治疗效果，随访期为 1 年。
选择 50 名上颌无牙且义齿固位和稳定性差，但上颌骨有足够骨量可植入种植体的患者。随机将患者分为四组或六组。评估种植体存活率、覆盖义齿存活率、临床评分、影像学骨高度变化和患者满意度。
49 名患者（1 名脱落）完成了 1 年的随访。1 年后，四组种植体的种植体存活率为 100%，六组种植体的种植体存活率为 99.3%（1 个种植体丢失）。两组的覆盖义齿存活率均为 100%。平均临床评分较低，且两组之间无差异（独立样本 t 检验）。四组种植体的平均边缘骨吸收为 0.24±0.32mm，六组种植体的平均边缘骨吸收为 0.25±0.29mm。两组患者的满意度均有所提高（配对样本 t 检验）。
在前上颌区域使用四个杆连接种植体支持覆盖义齿并不逊于使用六个杆连接种植体支持的覆盖义齿。种植体存活率高，种植体周围状况健康，两组患者的满意度均显著提高。
