Sellers Krysta, Powers John M, Kiat-Amnuay Sudarat
Former Resident, Graduate Prosthodontics, University of Texas School of Dentistry at Houston, Houston, Texas; Private practice, Dickinson, ND.
Clinical Professor of Oral Biomaterials, University of Texas School of Dentistry at Houston, Houston, Texas.
J Prosthet Dent. 2017 Feb;117(2):247-252. doi: 10.1016/j.prosdent.2016.06.014. Epub 2016 Sep 24.
The optimal retention of implant-supported ceramic crowns on zirconia abutments is a goal of prosthodontic treatment.
The purpose of this in vitro study was to evaluate the retentive strength of implant-supported IPS e.max CAD-CAM (e.max) crowns bonded to custom zirconia implant abutments with different cements.
An optical scan of a zirconia custom abutment and a complete-coverage modified crown was designed using an intraoral E4D scanner. One hundred twenty lithium disilicate crowns (IPS e.max CAD) were cemented to 120 zirconia abutment replicas with 1 of 6 cements: Panavia 21 (P21), Multilink Hybrid Abutment (MHA), RelyX Unicem 2 (RXU), RelyX Luting Plus (RLP), Ketac Cem (KC), and Premier Implant (PI). The specimens were stored at 37°C in 100% humidity for 24 hours. Half of the specimens were thermocycled for 500 cycles. The retentive force was measured using a pull-out test with a universal testing machine. Mean retentive strengths (MRS) were calculated using 2-way ANOVA and the Tukey-Kramer test (α=.05).
The MRS (MPa) after 24-hour storage were P21 (3.1), MHA (2.5), RXU (2.5), RLP (1.3), KC (0.9), and PI (0.5). The MRS after thermocycling were MHA (2.5), P21 (2.2), RLP (1.8), KC (1.4), RXU (1.1), and PI (0.3). P21 had the highest MRS after 24-hour storage (P<.001), but after thermocycling MHA had the highest MRS (P<.001). RXU showed a significant decrease in MRS after thermocycling (P<.05). Cement residue was mostly retained on the zirconia abutments for P21, while for the other cements' residue was retained on the lithium disilicate crowns.
The cements tested presented a range of retentive strengths, providing the clinician with a choice of more or less retentive cements. MHA was the most retentive cement after thermocycling. Thermocycling significantly affected the retentive strengths of the P21 and RXU cements.
在氧化锆基台上实现种植体支持的陶瓷冠的最佳固位是口腔修复治疗的一个目标。
本体外研究的目的是评估使用不同粘固剂粘结到定制氧化锆种植体基台上的种植体支持的IPS e.max CAD-CAM（e.max）全冠的固位强度。
使用口腔内E4D扫描仪对氧化锆定制基台和全冠覆盖改良牙冠进行光学扫描设计。将120颗二硅酸锂全冠（IPS e.max CAD）用6种粘固剂中的1种粘结到120个氧化锆基台复制体上：Panavia 21（P21）、Multilink Hybrid Abutment（MHA）、RelyX Unicem 2（RXU）、RelyX Luting Plus（RLP）、Ketac Cem（KC）和Premier Implant（PI）。将标本在37°C、100%湿度下储存24小时。一半标本进行500次热循环。使用万能试验机通过拔出试验测量固位力。使用双向方差分析和Tukey-Kramer检验（α = 0.05）计算平均固位强度（MRS）。
储存24小时后的MRS（MPa）分别为：P21（3.1）、MHA（2.5）、RXU（2.5）、RLP（1.3）、KC（0.9）和PI（0.5）。热循环后的MRS分别为：MHA（2.5）、P21（2.2）、RLP（1.8）、KC（1.4）、RXU（1.1）和PI（0.3）。储存24小时后P21的MRS最高（P <.001），但热循环后MHA的MRS最高（P <.001）。热循环后RXU的MRS显著降低（P <.05）。P21的粘固剂残渣大多保留在氧化锆基台上，而其他粘固剂的残渣则保留在二硅酸锂全冠上。
所测试的粘固剂呈现出一系列固位强度，为临床医生提供了不同固位力粘固剂的选择。热循环后MHA是固位力最强的粘固剂。热循环显著影响P21和RXU粘固剂的固位强度。
