Elagwany Mohamed Aly Mohamed Badr, Hamdy Amina Mohamed, Zohdy Maged Mohamed, Mahrous Aliaa, Tawfik Ahmed, Nabih Soha Osama
Faculty of dentistry, Fayoum University, fayoum, Badr City, Cairo, Egypt.
Faculty of dentistry, Ain Shams University, Cairo, Egypt.
BMC Oral Health. 2025 Jan 27;25(1):142. doi: 10.1186/s12903-025-05474-9.
The purpose of this study was to evaluate the effect of different preparation depths (0, 2 and 4 mm) of different restoration designs (classic endocrown design versus overlay design) on marginal adaptation of restorations fabricated of two different restorative materials (lithium disilicate and PEEK).
Sixty mandibular natural molars were collected as abutments for the restorations of this study, and grouped in three main groups of different cavity depths (0, 2 and 4). Each group was divided into two subgroups according to material of fabrication to (L) for lithium disilicate (IPS emax CAD, Ivoclar vivadent, Switzarland) and (P) for PEEK (Bio-hpp, Bredent, Germany). CAD/CAM milling technology was used for fabrication of restorations. After cementation of restorations over abutments, hydrothermal aging was performed, and then marginal adaptation was evaluated via micro CT technology.
Regarding cavity depths, there was a significant difference between different groups (p < 0.001). The highest value was found in samples with 4 mm extension (84.35 ± 18.16), followed by samples with 2 mm extension (66.52 ± 21.86), while the lowest value was found in samples without pulpal extension (59.41 ± 22.16). Post hoc pairwise comparisons showed samples with 4 mm extension to have a significantly higher value than samples without extension (p < 0.001). Regarding materials of fabrication, PEEK (85.32 ± 12.37) had a significantly higher value than Emax (54.86 ± 20.86) (p < 0.001).
Increasing intrapulpal cavity depths increases vertical marginal gap of lithium disilicate or PEEK restorations. Endocrowns fabricated of lithium disilicate show less marginal discrepancies than that of endocrowns fabricated of PEEK.
本研究旨在评估不同修复设计（经典嵌体冠设计与覆盖设计）的不同预备深度（0、2和4毫米）对由两种不同修复材料（二硅酸锂和聚醚醚酮）制成的修复体边缘适合性的影响。
收集60颗下颌天然磨牙作为本研究修复体的基牙，并根据不同的洞深分为三个主要组（0、2和4）。每组根据制作材料分为两个亚组，（L）代表二硅酸锂（IPS e.max CAD，义获嘉伟瓦登特公司，瑞士），（P）代表聚醚醚酮（Bio-hpp，Bredent公司，德国）。采用CAD/CAM铣削技术制作修复体。在将修复体粘结到基牙上后，进行热湿老化，然后通过显微CT技术评估边缘适合性。
关于洞深，不同组之间存在显著差异（p＜0.001）。在延伸4毫米的样本中值最高（84.35±18.16），其次是延伸2毫米的样本（66.52±21.86），而在未延伸至牙髓的样本中值最低（59.41±22.16）。事后两两比较显示，延伸4毫米的样本的值显著高于未延伸的样本（p＜0.001）。关于制作材料，聚醚醚酮（85.32±12.37）的值显著高于二硅酸锂（54.86±20.86）（p＜0.001）。
增加髓腔内洞深会增加二硅酸锂或聚醚醚酮修复体的垂直边缘间隙。由二硅酸锂制成的嵌体冠显示出比由聚醚醚酮制成的嵌体冠更小的边缘差异。
