Effect of virtual cement space and restorative materials on the adaptation of CAD-CAM endocrowns

BMC Oral Health

Research

Wenjuan Yan¹  Yuting Zeng¹  Ziting Zheng¹  Jilei Wang¹  Yuxin Zhang¹  Jiayao Mo¹  Zhiting Ling¹  Hebi Wang² 

[1] Department of Stomatology, Nanfang Hospital, Southern Medical University, 1838 N Guangzhou RD, Guangzhou, Guangdong, People’s Republic of China;Department of Stomatology, Nanfang Hospital, Southern Medical University, 1838 N Guangzhou RD, Guangzhou, Guangdong, People’s Republic of China;Department of Stomatology, The Third Affiliated Hospital of Guangzhou University of Chinese Medicine, Guangzhou, Guangdong, People’s Republic of China;

关键词: Marginal gap;    Cement space;    Endocrown;    Ceramic;    Composite resin;   

DOI  :  10.1186/s12903-022-02598-0

 received in 2022-06-08, accepted in 2022-11-15,  发布年份 2022

来源: Springer

【 摘 要 】

BackgroundThis study aimed to evaluate the effect of virtual cement space and restorative materials on the fit of computer-aided design and computer-aided manufacturing (CAD-CAM) endocrowns.MethodsA mandibular first molar tooth model received a butt joint margin endocrown preparation with a 2-mm occlusal thickness. Then, using a 3D-printing system, 120 copies of this prepared die were printed and assigned equally to three groups with different cement space settings (30, 60, and 120 μm) during the chairside CAD design. In the milling process, CAD-based models with a particular space setting were subdivided into four groups (n = 10) and fabricated from different CAD-CAM materials: Vita Suprinity (VS), Celtra Duo (CD), Lava Ultimate (LU), and Grandio blocs (GR). Finally, the endocrowns were stabilized over their corresponding models with siloxane and subjected to micro-computed tomography to measure the fit.ResultsThe cement space that was predesigned at 30 μm generated the largest marginal discrepancy (from 144.68 ± 22.43 μm to 174.36 ± 22.78 μm), which was significantly different from those at 60 μm and 120 μm (p < 0.001). The combination of VS or CD with a pre-setting cement space of 60 μm and the combination of LU or GR with a cement space of 120 μm showed better agreement between the predesigned and actual measured marginal gap widths. For internal adaptation, only the cement space set to 30 μm exceeded the clinically acceptable threshold (200 μm).ConclusionsThe setting of the cement space and restorative material significantly affected the marginal adaptation of CAD-CAM endocrown restorations. Considering the discrepancy between design and reality, different virtual cement spaces should be applied to ceramic and resin composite materials.

【 授权许可】

CC BY   
© The Author(s) 2022

【 图 表 】

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