Clinical Division of Conservative Dentistry and Periodontology, University Clinic of Dentistry, Medical University of Vienna, Vienna, Austria.
Clinical Division Unit-Dentistry Training, University Clinic of Dentistry, Medical University of Vienna, Vienna, Austria.
Clin Oral Implants Res. 2021 Feb;32(2):154-166. doi: 10.1111/clr.13685. Epub 2020 Dec 22.
The aim of this study was to evaluate thermal effects of ceramic and metal implant drills during implant site preparation using a standardised bovine model.
A total of 320 automated intermittent osteotomies of 10- and 16-mm drilling depths were performed using zirconium dioxide-based and stainless steel drills. Various drill diameters (2.0/ 2.2, 2.8, 3.5, 4.2 mm ∅) and different cooling methods (without/ with external saline irrigation) were investigated at room temperature (21 ± 1°C). Temperature changes were recorded in real time using two custom-built multichannel thermoprobes in 1- and 2-mm distance to the osteotomy site. For comparisons, a linear mixed model was estimated.
Comparing thermal effects, significantly lower temperatures could be detected with steel-based drills in various drill diameters, regardless of drilling depth or irrigation method. Recorded temperatures for metal drills of all diameters and drilling depths using external irrigation were below the defined critical temperature threshold of 47°C, whereas ceramic drills of smaller diameters reached or exceeded the harmful temperature threshold at 16-mm drilling depths, regardless of whether irrigation was applied or not. The results of this study suggest that the highest temperature changes were not found at the deepest point of the osteotomy site but were observed at subcortical and deeper layers of bone, depending on drill material, drill diameter, drilling depth and irrigation method.
This standardised investigation revealed drill material and geometry to have a substantial impact on heat generation, as well as external irrigation, drilling depth and drill diameter.
本研究旨在使用标准化牛模型评估陶瓷和金属种植体钻头在种植体预备过程中的热效应。
使用氧化锆基和不锈钢钻头进行了总计 320 次 10 和 16mm 钻孔深度的自动间歇截骨术。在室温（21±1°C）下，研究了不同的钻头直径（2.0/2.2、2.8、3.5、4.2mm∅）和不同的冷却方法（无/外生理盐水冲洗）。使用两个定制的双通道热探头实时记录骨切处 1 和 2mm 距离的温度变化。为了进行比较，采用了线性混合模型进行估计。
与热效应相比，各种钻头直径下的钢基钻头可检测到明显更低的温度，无论钻孔深度或冲洗方法如何。使用外部冲洗的所有直径和钻孔深度的金属钻头记录的温度均低于 47°C 的定义临界温度阈值，而较小直径的陶瓷钻头在 16mm 钻孔深度时达到或超过了有害温度阈值，无论是否应用冲洗。本研究结果表明，最高的温度变化不是在骨切的最深处发现的，而是取决于钻头材料、钻头直径、钻孔深度和冲洗方法，在皮质下和更深的骨层观察到。
这项标准化研究表明，钻头材料和几何形状对热生成有重大影响，此外还有外部冲洗、钻孔深度和钻头直径。
