Abstract：
The importance of aesthetics in children has increased over time. Therefore, this multicenter randomized clinical trial aimed to analyze and compare three-dimensional (3D)-printed resin crowns (RCs) as a potential alternative to stainless-steel crowns (SSCs) for restoring primary molars with extensive carious lesions. According to the null hypothesis, no statistically significant difference was observed in restoration failure between RC and SSC groups. A total of 56 primary molars after pulp treatment at two dental hospitals were included. After pulp treatment, the teeth were randomly divided into two groups: SSCs (n = 28) and RCs (n = 28). At 1 week and 3, 6 and 12 months, the Quigley-Hein plaque index (QHI), gingival index (GI), occlusal wear, and survival rate were assessed by examination, radiography and alginate impressions. No significant difference in QHI was observed between the two groups. However, the GI at 12 months and occlusal wear in the RC group were significantly higher than those in the SSC group (p < 0.05). The survival rates were 100% in the SSC group and 82.1% in the RC group (p = 0.047). Cracks and discoloration were also observed in the RCs. Within the limitations of this study, 3D-printed RCs are aesthetically superior to SSCs and clinically easy to repair. However, if clinical effectiveness and safety are improved, RCs could potentially become a viable aesthetic alternative in the future.
摘要：
美学在儿童中的重要性随着时间的推移而增加。因此,这项多中心随机临床试验旨在分析和比较三维(3D)打印树脂冠(RCs)作为不锈钢冠(SSC)的潜在替代品,用于修复伴有广泛龋齿的原发性磨牙.根据零假设，RC组和SSC组的修复失败差异无统计学意义.包括在两家牙科医院进行牙髓治疗后的总共56颗原发性磨牙。纸浆处理后，将牙齿随机分为两组：SSCs（n=28）和RCs（n=28）。在1周和3、6和12个月，Quigley-Hein菌斑指数（QHI），牙龈指数（GI），咬合磨损，通过检查评估生存率，射线照相术和藻酸盐印模。两组间QHI无显著差异。然而,RC组12个月时的GI和咬合磨损明显高于SSC组（p<0.05）。SSC组的生存率为100％，RC组为82.1％（p=0.047）。在RC中也观察到裂纹和变色。在这项研究的局限性内，3D打印的RC在美学上优于SSC，临床上易于修复。然而,如果临床有效性和安全性得到改善，RC可能在未来成为一种可行的美学替代品。
