Oral Surgery, Malo Clinic, Lisboa, Portugal.
Clin Implant Dent Relat Res. 2012 May;14 Suppl 1:e139-50. doi: 10.1111/j.1708-8208.2011.00395.x. Epub 2011 Oct 18.
Immediate implant function has become an accepted treatment modality for fixed restorations in totally edentulous mandibles, whereas experience from immediate function in the edentulous maxilla is limited.
The purpose of this study was to report on the medium- and long-term outcomes of a protocol for immediate function of four implants (All-on-4, Nobel Biocare AB, Göteborg, Sweden) supporting a fixed prosthesis in the completely edentulous maxilla.
This retrospective clinical study included 242 patients with 968 immediately loaded implants (Brånemark System TiUnite, Nobelspeedy, Nobel Biocare AB) supporting fixed complete-arch maxillary all-acrylic prostheses. A specially designed surgical guide was used to facilitate implant positioning and tilting of the posterior implants to achieve good bone anchorage and large interimplant distance for good prosthetic support. Follow-up examinations were performed at 6 months, 1 year, and thereafter every 6 months. Radiographic assessment of the marginal bone level was performed after 3 and 5 years in function. Survival was estimated at patient level and implant level using the Kaplan-Meier product limit estimation with 95% confidence intervals.
Nineteen immediately loaded implants were lost in seventeen patients, giving a 5-year survival rate estimation of 93% and 98% at patient and implant level, respectively. The survival rate of the prosthesis was 100%. The marginal bone level was, on average, 1.52 mm (standard deviation [SD] 0.3 mm) and 1.95 mm (SD 0.4 mm) from the implant/abutment junction after 3 and 5 years, respectively.
The high survival rates at patient and implant level indicates that the immediate-function concept for completely edentulous maxillae using the present protocol is viable in the medium- and long-term outcomes.
即刻种植功能已成为无牙下颌固定修复的一种可接受的治疗方式，而无牙上颌即刻功能的经验有限。
本研究旨在报告即刻功能方案（All-on-4，Nobel Biocare AB，哥德堡，瑞典）在完全无牙上颌中使用四颗种植体（Brånemark System TiUnite，Nobelspeedy，Nobel Biocare AB）支持固定修复体的中短期效果。
本回顾性临床研究纳入了 242 名患者，共 968 颗即刻负载种植体（Brånemark System TiUnite，Nobelspeedy，Nobel Biocare AB），用于支撑全上颌无牙全亚克力修复体。使用专门设计的外科导板来辅助种植体定位和后牙种植体倾斜，以实现良好的骨锚固和较大的种植体间距离，从而获得良好的修复体支持。在 6 个月、1 年和之后每 6 个月进行随访检查。在功能状态下，在 3 年和 5 年后进行放射评估边缘骨水平。使用 Kaplan-Meier 乘积限估计法和 95%置信区间，在患者和种植体水平上估计生存率。
17 名患者中有 19 颗即刻负载种植体丢失，5 年生存率估计分别为 93%和 98%，患者和种植体水平。修复体的生存率为 100%。平均边缘骨水平分别为种植体/基台交界处 1.52 毫米（标准差 [SD] 0.3 毫米）和 1.95 毫米（SD 0.4 毫米），分别在 3 年和 5 年后。
患者和种植体水平的高生存率表明，使用本方案即刻功能的完全无牙上颌的概念在中短期效果上是可行的。
