Department of Periodontology, Faculty of Odontology, University of Malmö, Malmö, Sweden.
Division of Oral Surgery, University Clinic of Dentistry, Medical University of Vienna, Vienna, Austria.
J Periodontol. 2021 Apr;92(4):592-601. doi: 10.1002/JPER.20-0222. Epub 2020 Sep 16.
To evaluate whether buccal bone thickness (BBT), implant diameter, and abutment/crown material influence the accuracy of cone-beam computed tomography (CBCT) to determine the buccal bone level at titanium implants.
Two implant beds (i.e., narrow and standard diameter) were prepared in each of 36 porcine bone blocks. The implant beds were positioned at a variable distance from the buccal bone surface; thus, resulting in three BBT groups (i.e., >0.5 to 1.0; >1.0 to 1.5; >1.5 to 2.0 mm). In half of the blocks, a buccal bone dehiscence of random extent ("depth") was created and implants were mounted with different abutment/crown material (i.e., titanium abutments with a metal-ceramic crown and zirconia abutments with an all-ceramic zirconia crown). The distance from the implant shoulder to the buccal bone crest was measured on cross-sectional CBCT images and compared with the direct measurements at the bone blocks.
While abutment/crown material and implant diameter had no effect on the detection accuracy of the buccal bone level at dental implants in CBCT scans, BBT had a significant effect. Specifically, when BBT was ≤1.0 mm, a dehiscence was often diagnosed although not present, that is, the sensitivity was high (95.8%), but the specificity (12.5%) and the detection accuracy (54.2%) were low. Further, the average measurement error of the distance from the implant shoulder to the buccal bone crest was 1.6 mm.
Based on the present laboratory study, BBT has a major impact on the correct diagnosis of the buccal bone level at dental titanium implants in CBCT images; in cases where the buccal bone is ≤1 mm thick, detection of the buccal bone level is largely inaccurate.
评估颊侧骨厚度（BBT）、种植体直径和基台/冠材料是否会影响锥形束 CT（CBCT）确定钛种植体颊侧骨水平的准确性。
在 36 个猪骨块中，每个骨块制备两个种植体床（即窄直径和标准直径）。种植体床放置在距颊侧骨表面不同距离处，从而产生三个 BBT 组（即>0.5 至 1.0mm、>1.0 至 1.5mm、>1.5 至 2.0mm）。在一半的骨块中，创建了随机程度的颊侧骨缺损（“深度”），并用不同的基台/冠材料（即金属陶瓷冠的钛基台和全陶瓷氧化锆冠的氧化锆基台）安装种植体。在 CBCT 图像的横截面上测量从种植体肩到颊侧骨嵴的距离，并与骨块上的直接测量值进行比较。
虽然基台/冠材料和种植体直径对 CBCT 扫描中种植体颊侧骨水平的检测准确性没有影响，但 BBT 有显著影响。具体来说，当 BBT 小于等于 1.0mm 时，即使不存在，也常常诊断为骨缺损，即灵敏度高（95.8%），但特异性（12.5%）和检测准确性（54.2%）较低。此外，从种植体肩到颊侧骨嵴的距离的平均测量误差为 1.6mm。
根据本实验室研究，BBT 对 CBCT 图像中钛种植体颊侧骨水平的正确诊断有重大影响；在颊侧骨厚度小于等于 1mm 的情况下，颊侧骨水平的检测大多不准确。
