Luis Felipe Guilardi, associate researcher, Post-Graduate Program in Oral Science (Prosthodontics Unit), Faculty of Dentistry, Federal University of Santa Maria (UFSM), Santa Maria, Rio Grande do Sul State, Brazil.
Gabriel Kalil Rocha Pereira, MsciD, PhD, adjunct professor, Post-Graduate Program in Oral Science (Prosthodontics Units), Faculty of Dentistry, Federal University of Santa Maria (UFSM), Santa Maria, Rio Grande do Sul State, Brazil.
Oper Dent. 2022 Jul 1;47(4):461-472. doi: 10.2341/20-143-L.
This study investigated the fatigue failure load of simplified monolithic yttria partially stabilized zirconia polycrystal restorations cemented to a dentin-like substrate using different luting systems. Disc-shaped ceramic (Zenostar T, 10 mm Ø × 0.7 mm thick) and dentin-like substrate (10 mm Ø × 2.8 mm thick) were produced and randomly allocated into eight groups, without or with thermocycling (TC=5-55°C/12,000×): "cement" (RelyX Luting 2 - glass ionomer cement [Ion], [Ion/TC]; RelyX U200 - self-adhesive resin cement [Self], [Self/TC]; Single Bond Universal+RelyX Ultimate - MDP-containing adhesive + resin cement [MDPAD + RC], [MDP-AD + RC/TC]; ED Primer II+Panavia F 2.0 - Primer + MDP-containing resin cement [PR + MDP-RC], [PR + MDP-RC/TC])). Each luting system was used as recommended by the manufacturer. Staircase methodology (20 Hz; 250,000 cycles) was applied for obtaining the fatigue failure loads. Fractographic characteristics were also assessed. At baseline, the Ion group presented the lowest fatigue load, although it was statistically similar to the Self group. The resin-based cement systems presented the highest fatigue performance, with the Ion group being only statistically equal to the Self group. Thermocycling influenced the groups differently. After aging, the MDP-AD + RC presented the highest mean, followed by the PR + MDP-RC and Self groups, while the Ion group had the lowest mean. Fractographic analysis depicted all failures as radial cracks starting at the zirconia intaglio surface. The luting system with MDP-containing adhesive applied prior to the resin cement presented the highest fatigue failure load after aging, presenting the best predictability of stable performance. Despite this, monolithic zirconia presents high load-bearing capability regardless of the luting agent.
本研究调查了使用不同粘固系统粘固于类似牙本质基底的简化整体氧化钇部分稳定氧化锆多晶修复体的疲劳失效负荷。制备了圆盘状陶瓷（Zenostar T，10mmØ×0.7mm 厚）和类似牙本质基底（10mmØ×2.8mm 厚），并将其随机分为 8 组，分为无热循环（TC=5-55°C/12,000×）和有热循环（TC=5-55°C/12,000×）两组：“粘固剂”（RelyX Luting 2-玻璃离子水门汀[Ion]，[Ion/TC]；RelyX U200-自粘接树脂水门汀[Self]，[Self/TC]；Single Bond Universal+RelyX Ultimate-MDP 含粘接剂+树脂水门汀[MDPAD+RC]，[MDPAD+RC/TC]）。每种粘固系统均按制造商的建议使用。采用阶梯法（20Hz；250,000 次循环）获得疲劳失效负荷。还评估了断裂特征。在基线时，Ion 组的疲劳负荷最低，但与 Self 组无统计学差异。树脂基粘固系统的疲劳性能最高，Ion 组仅与 Self 组有统计学差异。热循环对各组的影响不同。老化后，MDPAD+RC 组的平均疲劳失效负荷最高，其次是 PR+MDP-RC 组和 Self 组，而 Ion 组的平均疲劳失效负荷最低。断裂特征分析显示所有失效均为从氧化锆凹面开始的放射状裂纹。在老化后，使用含 MDP 粘接剂的粘固系统的疲劳失效负荷最高，表现出稳定性能的最佳可预测性。尽管如此，无论使用何种粘固剂，整体氧化锆都具有较高的承载能力。
