Ibrahim Shereen Hafez, Amr Haitham, Hassan Ahmed A, Elzohairy Ahmed
Faculty of Dentistry, Cairo University, Egypt.
Faculty of Dentistry, Fayoum University, Egypt.
Heliyon. 2022 May 19;8(5):e09466. doi: 10.1016/j.heliyon.2022.e09466. eCollection 2022 May.
The restoration durability is essentially governed by optimum marginal integrity of an indirect restoration that is obtained and maintained by essential factors. This study aimed to evaluate the internal gap of indirect restorations fabricated from CAD/CAM composite blocks versus ceramic blocks in badly broken teeth using cone beam CT (CBCT) to determine their internal fit accuracy over the cast.
Fifty-four participants were allocated into two groups: composite blocks or ceramic blocks. The trial participants and assessors were blinded to the material assignment, whereas the operator was not. Cavity preparation was performed followed by cavity optimization and impression taking. The produced master cast was scanned, restoration was designed using Exocad 2019 software and the final restoration was milled. The restoration was doubled-checked on the cast for internal fit using cone beam computed tomography (CBCT), and intraorally for interproximal contact and marginal adaptation before final cementation. CBCT measurements were collected and statistically analyzed. Restoration was cemented with resin cement and was immediately assessed clinically, then after one year and two years of follow-up periods.
Results of an independent t-test revealed Composite blocks samples (0.25mm ± 0.03) to have a significantly better adaptation than ceramic blocks samples (0.29 mm ± 0.04) (p = 0.008).
Both materials have acceptable internal adaptation with a noticed difference reflected in their clinical performance.
Both indirect esthetic CAD/CAM restorations exhibit acceptable internal and marginal adaptation in posterior teeth however, composite blocks have a better adaptation than ceramic blocks.
This trial was registered in clinicaltrials.gov (NCT04784676).
修复体的耐久性本质上取决于间接修复体的最佳边缘完整性，而这种完整性是由关键因素获得并维持的。本研究旨在使用锥形束CT（CBCT）评估严重折断牙齿中由CAD/CAM复合树脂块与陶瓷块制作的间接修复体的内部间隙，以确定它们相对于铸型的内部贴合精度。
54名参与者被分为两组：复合树脂块组或陶瓷块组。试验参与者和评估者对材料分配不知情，而操作者知情。进行窝洞预备，随后进行窝洞优化和取模。对制作的主模型进行扫描，使用Exocad 2019软件设计修复体并进行最终修复体的铣削。在最终粘结前，使用锥形束计算机断层扫描（CBCT）在模型上对修复体的内部贴合进行二次检查，并在口内检查邻面接触和边缘适应性。收集CBCT测量数据并进行统计分析。修复体用树脂粘结剂粘结，并立即进行临床评估，然后在随访1年和2年后再次评估。
独立t检验结果显示，复合树脂块样本（0.25mm±0.03）的适应性明显优于陶瓷块样本（0.29mm±0.04）（p = 0.008）。
两种材料都具有可接受的内部适应性，但其临床性能存在明显差异。
两种间接美学CAD/CAM修复体在后牙中均表现出可接受的内部和边缘适应性，然而，复合树脂块的适应性优于陶瓷块。
本试验已在ClinicalTrials.gov（NCT04784676）注册。
