Federlin Marianne, Schmidt Sebastian, Hiller Karl-Anton, Thonemann Birger, Schmalz Gottfried
University of Regensburg Dental School, Department of Operative Dentistry and Periodontology, Regensburg, Germany.
Oper Dent. 2004 Sep-Oct;29(5):560-70.
The influence of three different cavity preparations on the marginal integrity of partial ceramic crowns (PCC) luted with four different luting systems was investigated in this in vitro study. PCC preparations were performed in 144 extracted human molars using one of the following preparation designs (n=48/preparation): A--Coverage of functional cusps/butt joint preparation; B--horizontal reduction of functional cusps and C--complete reduction of functional cusps/butt joint preparation. Non-functional cusps were not covered; mesial and distal proximal boxes were extended 1 mm below the cemento-enamel-junction. PCC were fabricated from Vita Mark II ceramic (Vita) with a Cerec 3 Unit (Sirona) and adhesively luted to the cavities using the following luting systems: (VL) Variolink II/Excite (Vivadent), (PA) Panavia F/ED Primer (Kuraray), (DY) Dyract/Prime & Bond NT (DeTrey/Dentsply) and (FU) Fuji Plus/GC Cavity Conditioner (GC). Samples were simultaneously exposed to thermocycling and mechanical loading (TC: 5000x8-55 degrees C, 30 seconds/cycle; ML: 500000x72.5N, 1.6Hz). Marginal adaptation was assessed by evaluating dye penetration on multiple sections by relating the actual penetration distance to the maximal length of the corresponding cavity wall (100%). Ceramic- and tooth-luting material interfaces were evaluated separately. The data were statistically analyzed with the Mann Whitney U-test and Wilcoxon Rank Sumtest. In general, no significant differences could be found between preparations A, B and C. The combination of preparation C and luting material PA showed a tendency for the lowest dye penetration values, especially within dentin (30%). Significant differences could be determined between luting materials: Composite luting materials PA (0%) and VL (1%) revealed less dye penetration than the compomer DY (6%) and resin-modified glass ionomer cement (RMGIC) FU (26%); use of RMGIC caused fractures of the restorations. The dentin/luting material interface showed the highest penetration values, ranging from 17% to 100%. In conclusion, with adhesively bonded partial ceramic crowns, the choice of luting material proved to be more relevant than preparation design under the limitations of this study. Margins below the cemento-enamel junction reveal significant loss of adhesion in spite of subsequent application of adhesive luting techniques. RMGIC cannot be recommended as a luting material for feldspathic PCC.
在这项体外研究中，调查了三种不同的窝洞预备方式对采用四种不同粘结系统粘结的部分陶瓷冠（PCC）边缘完整性的影响。在144颗拔除的人类磨牙上进行PCC预备，采用以下预备设计之一（每种预备方式n = 48）：A——功能性尖覆盖/对接边缘预备；B——功能性尖水平磨除；C——功能性尖完全磨除/对接边缘预备。非功能性尖未覆盖；近中及远中邻面盒向牙骨质-釉质界下方延伸1mm。PCC由Vita Mark II陶瓷（Vita）通过Cerec 3单元（Sirona）制作，并使用以下粘结系统粘结到窝洞中：（VL）Variolink II/Excite（Vivadent）、（PA）Panavia F/ED Primer（可乐丽）、（DY）Dyract/Prime & Bond NT（迪特里/登士柏）和（FU）Fuji Plus/GC Cavity Conditioner（GC）。样本同时接受热循环和机械加载（热循环：5000次循环，8 - 55℃，每循环30秒；机械加载：500000次循环，72.5N，1.6Hz）。通过评估多个切片上的染料渗透情况来评估边缘适应性，将实际渗透距离与相应窝洞壁的最大长度相关联（100%）。分别评估陶瓷与牙齿-粘结材料界面。数据采用Mann Whitney U检验和Wilcoxon秩和检验进行统计学分析。总体而言，在预备方式A、B和C之间未发现显著差异。预备方式C与粘结材料PA的组合显示出染料渗透值最低的趋势，尤其是在牙本质内（30%）。在粘结材料之间可确定存在显著差异：复合粘结材料PA（0%）和VL（1%）的染料渗透比复合体DY（6%）和树脂改性玻璃离子水门汀（RMGIC）FU（26%）少；使用RMGIC导致修复体出现断裂。牙本质/粘结材料界面显示出最高的渗透值，范围从17%到100%。总之，在本研究的限制条件下，对于粘结式部分陶瓷冠，粘结材料的选择比预备设计更为重要。尽管随后应用了粘结技术，但牙骨质-釉质界下方的边缘显示出显著的粘结丧失。RMGIC不能推荐作为长石质PCC的粘结材料。
