To compare the clinical outcomes of modified digital custom implant impression and conventional custom implant impression method in the upper anterior region.

A prospective randomized clinical trial was conducted on patients who had received dental implants in upper anterior region in Jianli Stomatological Hospital of Dongguan from March 2021 to December 2021, and needed implant-supported prostheses. After provisional crowns were used to obtain ideal emergence profile, a random number lottery method was used to determine the groups. Patients with modified digital custom impression method were included in the experimental group, and those with conventional custom impression method were included in the control group. The primary evaluation criteria were the accuracy of replication of the emergence profile, and the secondary evaluation criteria were impression-taking time, accuracy of occlusal and adjacent relationships, and VAS score of comfort. Two-sample t-test was used to analyze group differences in accuracy of emergence profile (software assessment) , time to take impression and VAS score. Wilcoxon rank-sum test was used to analyze group differences in accuracy of occlusion, interdental relationships and emergence profile (subjective assessment) , and patients VAS score after final restoration.

A total of 40 patients were included in the study with 20 patients in each group. Acurracy of emergence profile (software assessment) of the digital group was (0.39 ± 0.09) mm, which was significantly less than that of the conventional group (0.60 ± 0.09) mm (t = -7.525, P<0.001) . There was no significant difference in the accuracy of occlusion (Z = -1.025, P = 0.305) and interdental relationships (Z = -1.233, P = 0.218) . The accuracy of emergence profile (subjective assessment) of the experimental group was significantly better than that of the conventional group (Z = -4.684, P<0.001) . The VAS score of the digital group (2.45 ± 1.10) was significantly lower than that of the conventional group (7.00 ± 1.45) (t = 11.179, P<0.001) .

The modified digital custom impression and conventional custom impression method could both get satisfying clinical outcomes. Moreover, the modified digital custom impression is more effective, precise and comforting than the conventional custom impression method.