Department of Prosthodontics and Digital Technology, School of Dental Medicine, Stony Brook University, New York, NY 11794-8712, USA.
Department of Periodontology, School of Dental Medicine, Stonybrook University, New York, NY 11794-8712, USA.
Medicina (Kaunas). 2021 Sep 6;57(9):940. doi: 10.3390/medicina57090940.
To evaluate the condensation and the microarchitecture of implant bed walls of sites prepared with counterclockwise drilling with tapered implant drills using optical coherence tomography. : Four drill designs with different wall and tip angles were used. Polyurethane laminas resembling type IV bone microarchitecture were superimposed and clamped with a vice to simulate the coronal, middle, and apical aspects of the implant site. Twenty implant beds were prepared at 1200 rpm in clockwise (control) and counterclockwise (test) directions (N = 160). Optical coherence tomography (OCT) was used to evaluate the condensation and microarchitecture characteristics of the implant bed walls. The relative condensation was calculated using the Image J software Bone application. The microarchitecture was evaluated in reconstructed 3D volumes in XY, XZ, and YZ sections. Statistical analysis was performed using one-way ANOVA. Dunnet test was applied to determine differences between groups. Significance was set as < 0.05. : Counterclockwise drilling (Test) condensed and changed the microarchitecture of the apical regions for all the implant beds in all of the groups when compared to clockwise drilling (control). The apical region of test groups showed the highest relative bone condensation ( = 0.026) when compared to controls. : The direction of rotation (counterclockwise drilling) and not the design of tapered drills (tip and wall angles) is responsible for the condensation at the apical area observed in polyurethane blocks. The OCT method can be used for the evaluation of changes in density and microstructure of polyurethane blocks.
使用光相干断层扫描评估使用逆时针旋转锥形种植钻制备的种植床壁的冷凝和微观结构。：使用了四种具有不同壁角和尖端角度的钻头设计。将类似于 IV 型骨微观结构的聚氨酯层叠加并用虎钳夹住，以模拟种植部位的冠状、中部和根尖部分。在顺时针（对照）和逆时针（测试）方向（N = 160）以 1200 rpm 的速度制备了 20 个种植床。使用光相干断层扫描（OCT）评估种植床壁的冷凝和微观结构特征。使用 Image J 软件 Bone 应用程序计算相对冷凝度。在 XY、XZ 和 YZ 截面的重建 3D 体积中评估微观结构。使用单向方差分析进行统计分析。应用 Dunnett 检验确定组间差异。设定显著性水平为 < 0.05。：与顺时针钻孔（对照）相比，逆时针钻孔（测试）冷凝并改变了所有组中所有种植床的根尖区域的微观结构。与对照组相比，测试组的根尖区域显示出最高的相对骨冷凝度（= 0.026）。：旋转方向（逆时针）而不是锥形钻头的设计（尖端和壁角）负责观察到的聚氨酯块根尖区域的冷凝。OCT 方法可用于评估聚氨酯块密度和微观结构的变化。
