Departement of Oral Surgery, Dental University of Lyon, Lyon, France.
Clin Implant Dent Relat Res. 2013 Apr;15(2):198-204. doi: 10.1111/j.1708-8208.2011.00342.x. Epub 2011 Apr 7.
The objectives of this radiographic study were to determine to what degree the available residual bone area for implant placement was underestimated on panoramic radiographs (by comparison with multislice computed tomography CT/cone beam CT images combined with planning software) and to what degree the rate of severely resorbed posterior maxillae requiring sinus lift was overestimated on panoramic radiographs (by comparison with planning software in combination with strategic implant placement).
During a 2-year period, every patient who presented for the placement of implants in the posterior maxilla was examined by three practitioners to discuss the treatment plan. When two to three practitioners indicated a sinus lift with creation of a lateral window, a CT scan was performed and examined using dedicated three-dimensional software by a clinician familiar with the Computer Assisted Design/ Computer Assisted Manufacturing (CAD/CAM) implant placement protocol. For each tooth to be replaced, the presence of anatomical features such as anterior or posterior wall, palatal curvature, and septa were examined in view of the placement of an 8-mm or longer implant.
One hundred one patients were studied in this case series for the treatment of 135 edentulous spans accounting for 301 missing teeth. After examination of the CT data on the three-dimensional software, 202 teeth (67.1%) could be replaced using a CAD/CAM procedure; 60.7% of the edentulous spans could be completely repaired by a crown or bridge supported by implants. In addition, 67.3% of edentulism with no teeth posterior to the span could be completely repaired using a fixed prosthesis supported by implants.
This radiological study demonstrates that the use of a panoramic exam for oral implant planning in severely resorbed maxillae overestimates the need for a sinus augmentation procedure when compared with the use of both three-dimensional planning software and strategic implant placement on small remaining bone volume.
本影像学研究的目的是确定在全景片（与多层面 CT/锥形束 CT 图像结合规划软件相比）上评估种植体可用剩余骨量的程度存在多大程度的低估，以及在全景片（与规划软件结合，采用战略性种植体植入位置）上评估严重吸收的上颌后牙需要行窦底提升的程度存在多大程度的高估。
在 2 年期间，每一位需要在后上颌植入种植体的患者都由三位医生进行检查，以讨论治疗计划。当两位或三位医生建议行窦底提升并创建外侧窗口时，会进行 CT 扫描，并由一位熟悉计算机辅助设计/计算机辅助制造（CAD/CAM）种植体植入方案的临床医生使用专用的三维软件进行检查。对于每颗要替换的牙齿，根据植入 8 毫米或更长种植体的位置，检查解剖特征的存在情况，例如前壁或后壁、腭弓曲度和鼻中隔。
在这项病例系列研究中，101 名患者的 135 个无牙颌间隙（共 301 颗缺失牙）接受了治疗。在对三维软件上的 CT 数据进行检查后，202 颗牙（67.1%）可以通过 CAD/CAM 程序进行替换；60.7%的无牙颌间隙可以通过牙冠或牙桥完全修复，牙桥由植入体支撑。此外，67.3%的后牙区无牙颌可以通过植入体支撑的固定义齿完全修复。
这项影像学研究表明，与使用三维规划软件和在剩余小骨量上采用战略性种植体植入位置相比，在严重吸收的上颌中，使用全景片进行口腔种植体规划会高估窦底提升手术的需求。
