Krennmair Gerald, Krainhöfner Martin, Piehslinger Eva
Department of Prosthodontics, Dental School, University of Vienna, Austria.
Int J Oral Maxillofac Implants. 2008 Mar-Apr;23(2):343-52.
The aim of the present retrospective investigation was to evaluate implant-supported maxillary overdentures using either anterior (group 1) or posterior (group 2) maxillary implant placement.
Maxillary overdentures were planned with support by either 4 implants placed in the maxillary anterior region (group 1) or 6 to 8 implants placed in augmented maxillary posterior regions (group 2, bilateral sinus augmentation) and anchored either on an anterior or on 2 bilaterally placed milled bars. Cumulative implant survival rate, peri-implant conditions (marginal bone loss, pocket depth, Plaque Index, Gingival Index, Bleeding Index, and Calculus Index) and the incidence and type of prosthodontic maintenance were assessed and compared for the 2 groups. In addition, the cumulative survival rate for implants placed in grafted regions was compared with that of implants placed in nongrafted regions.
Thirty-four patients (16 for group 1 and 18 for group 2) with 179 implants were available for follow-up examination after a mean period of 42.1 +/- 20.1 months. Four initially placed implants failed to osseointegrate and were replaced, but no further losses were seen during the loading period, for a 5-year cumulative implant survival rate of 978%. No differences in implant survival rates were seen between either the group-1 (98.4%) and group-2 (97.4%) concepts or nongrafted (98.0%) and grafted (97.5%) implants. The peri-implant parameters showed a healthy soft tissue, good oral hygiene, and an acceptable degree of peri-implant marginal bone loss. The rigid fixation of all overdentures was associated with a low incidence of prosthodontic maintenance, without any significant differences between the 2 groups.
In well-planned overdenture treatment programs, a high survival rate and excellent peri-implant conditions can be achieved for implants placed in the anterior or posterior maxilla. Rigid anchorage of maxillary overdentures either on an extended anterior milled bar or on 2 bilateral posterior milled bars provides for a low incidence of prosthodontic maintenance.
本回顾性研究的目的是评估采用上颌前部（第1组）或后部（第2组）种植体植入的种植体支持上颌覆盖义齿。
计划制作上颌覆盖义齿，第1组在上颌前部区域植入4枚种植体进行支持，第2组在上颌后部增隙区域植入6至8枚种植体（双侧鼻窦增隙），并分别固定在前部或双侧放置的2根研磨杆上。评估并比较两组的种植体累积存留率、种植体周围状况（边缘骨吸收、牙周袋深度、菌斑指数、牙龈指数、出血指数和牙石指数）以及修复体维护的发生率和类型。此外，比较种植于移植区的种植体与种植于非移植区的种植体的累积存留率。
34例患者（第1组16例，第2组18例）共植入179枚种植体，平均随访42.1±20.1个月。4枚最初植入的种植体未能实现骨结合而被替换，但在加载期未出现进一步的种植体丢失，5年种植体累积存留率为97.8%。第1组（98.4%）和第2组（97.4%）的种植体存留率以及非移植种植体（98.0%）和移植种植体（97.5%）之间均未见差异。种植体周围参数显示软组织健康、口腔卫生良好且种植体周围边缘骨吸收程度可接受。所有覆盖义齿的刚性固定与修复体维护发生率低相关，两组之间无显著差异。
在精心规划的覆盖义齿治疗方案中，上颌前部或后部植入的种植体可实现高存留率和良好的种植体周围状况。上颌覆盖义齿在前部延长研磨杆或双侧后部2根研磨杆上的刚性固定可使修复体维护发生率较低。
