Department of Periodontology, Endodontology and Cariology, University Center for Dental Medicine Basel, University of Basel, Basel, Switzerland.
Centre for Craniofacial and Regenerative Biology, Dental Institute, King's College London, London, UK.
Clin Oral Implants Res. 2018 Jan;29(1):82-90. doi: 10.1111/clr.13071. Epub 2017 Oct 17.
The purpose of this study was to analyze the cement excess produced when cementing CAD/CAM-fabricated lithium disilicate (L) or zirconium dioxide (Z) crowns using adhesive cement (A) or resin-modified glass ionomer cement (B). Three different cementation techniques were applied: palatal venting (PV), pre-cementation with custom analogs (CA), and conventional standard procedure (SP).
Seventy-two crowns (36 each material) were assigned to 12 experimental groups depending on the restoration material (L, Z), type of cement (A, B), and cementation technique (PV, CA, SP). Weight measurements were taken during cementation, and the amounts of excess cement, cement retained in crown, and relative excess cement were calculated and statistically analyzed.
A significant direct relation between the amounts of cement applied and excess cement was observed in groups CA and SP. Vented crowns showed least amounts of marginal excess cement (0.8 ± 0.3 μl) followed by CA (4.2 ± 1.1 μl) and SP (8.8 ± 2.5 μl; p < .001). In CA, 32.1% less excess cement (95%CI: 28.4, 35.7) was produced than in the SP group (p < .001), but 27.4% more than in the PV group (95%CI: 23.8,31.0; p < .001). Overall, slightly smaller amounts of adhesive cement (A) than of glass ionomer cement (B) were retained in crowns.
Using crown venting was the most effective measure to reduce the amount of marginal excess cement, followed using a pre-cementation device. To keep the marginal excess cement of one-piece zirconia implants to a minimum, both techniques should be considered for clinical application.
本研究旨在分析使用粘结剂（A）或树脂改性玻璃离子水门汀（B）黏固 CAD/CAM 制作的氧化锂（L）或氧化锆（Z）全瓷冠时产生的多余水泥。应用了三种不同的黏固技术：腭侧通气（PV）、预黏固用定制模拟体（CA）和常规标准程序（SP）。
将 72 个牙冠（每种材料 36 个）根据修复材料（L、Z）、水泥类型（A、B）和黏固技术（PV、CA、SP）分为 12 个实验组。在黏固过程中进行重量测量，并计算和统计分析多余水泥量、牙冠内保留的水泥量和相对多余水泥量。
在 CA 和 SP 组中，观察到应用的水泥量与多余水泥量之间存在显著的直接关系。通气牙冠显示出最少的边缘多余水泥量（0.8±0.3μl），其次是 CA（4.2±1.1μl）和 SP（8.8±2.5μl；p<0.001）。在 CA 组中，与 SP 组相比，产生的多余水泥量减少了 32.1%（95%CI：28.4，35.7）（p<0.001），但与 PV 组相比，增加了 27.4%（95%CI：23.8，31.0；p<0.001）。总体而言，牙冠内保留的粘结剂（A）量略小于玻璃离子水泥（B）量。
使用牙冠通气是减少边缘多余水泥量最有效的方法，其次是使用预黏固装置。为了将一体式氧化锆种植体的边缘多余水泥量保持在最低水平，这两种技术都应考虑用于临床应用。
