Arslan Emel, Keles Ali
Faculty of Dentistry, Department of Prosthodontic, Bolu Abant Izzet Baysal University, Gölköy Campus, 14030, Bolu, Turkey.
Faculty of Dentistry, Department of Endodontics, Bolu Abant Izzet Baysal University, Bolu, Turkey.
Clin Oral Investig. 2025 Aug 12;29(9):408. doi: 10.1007/s00784-025-06497-w.
This study evaluates cementation gap, cement volume, and porosity levels in three-dimensional crown restorations using four permanent resin materials and printers, and examines changes after thermomechanical ageing.
In the study, phantom models prepared on the maxillary first premolar were used, and the digital scanning, CAD design, 3D printing, cementation, and ageing processes were carried out according to standard protocols. The samples were divided into four groups based on the permanent resin material used: Group C (Methacrylate-based resin), Group S (UDMA-based composite), Group P (Bis-GMA/TEGDMA-based), and Group V (Bis-EMA/UDMA-based). All samples were designed with a 50 μm virtual cementation gap and evaluated by micro-CT before and after ageing.
The findings showed statistically significant differences between the groups in terms of cementation gap and porosity volume (p < 0.001). The lowest void volume and porosity were measured in the group C, while the highest values were observed in the group S. No significant difference was observed between the groups in terms of total cement volume. Additionally, a strong positive correlation was found between cement volume and porosity.
The obtained data reveal that the resin material used and the production process play a decisive role in the internal compatibility of restorations. Thermomechanical ageing, on the other hand, caused significant changes, particularly in structural properties. These results indicate that permanent resin restorations produced by 3D printing should be evaluated for their clinical viability considering cement gap and porosity behavior.
This study has revealed that the cementation gap and porosity levels of permanent resin crowns produced with a 3D printer vary significantly depending on the type of material used and the production process. Therefore, in clinical applications, not only aesthetic and mechanical properties but also cementation compatibility and microstructural properties should be taken into consideration.
本研究评估使用四种永久性树脂材料和打印机制作的三维冠修复体中的粘结间隙、粘结剂体积和孔隙率水平，并检测热机械老化后的变化。
在本研究中，使用在上颌第一前磨牙上制备的模型，按照标准方案进行数字扫描、CAD设计、3D打印、粘结和老化过程。根据所使用的永久性树脂材料将样本分为四组：C组（甲基丙烯酸酯基树脂）、S组（基于UDMA的复合材料）、P组（基于双-GMA/TEGDMA）和V组（基于双-EMA/UDMA）。所有样本均设计有50μm的虚拟粘结间隙，并在老化前后通过微型CT进行评估。
研究结果表明，各组之间在粘结间隙和孔隙体积方面存在统计学上的显著差异（p < 0.001）。C组的空隙体积和孔隙率最低，而S组观察到最高值。各组之间在总粘结剂体积方面未观察到显著差异。此外，发现粘结剂体积与孔隙率之间存在强正相关。
获得的数据表明，所使用的树脂材料和生产工艺在修复体的内部兼容性方面起决定性作用。另一方面，热机械老化引起了显著变化，特别是在结构性能方面。这些结果表明，考虑到粘结间隙和孔隙行为，应对3D打印生产的永久性树脂修复体的临床可行性进行评估。
本研究表明，3D打印机制作的永久性树脂冠的粘结间隙和孔隙率水平根据所使用的材料类型和生产工艺而有显著差异。因此，在临床应用中，不仅应考虑美学和机械性能，还应考虑粘结兼容性和微观结构性能。
