[Evaluation of the trueness and tissue surface adaptation of digital and traditional complete denture bases].

Purpose: To compare the trueness of the tissue surface of the complete denture base among the digital cutting complete denture, the digital 3D printing complete denture and the conventional complete denture.

Methods: Three edentulous patients were selected, and three complete dentures were made for each case. Cutting dentures (cutting group), 3D printed dentures(printing group) were considered as the experimental groups, traditional dentures (traditional group) were considered as the control group. The tissue surface of complete denture model and denture base were scanned and their 3D data were obtained. Geomagic software was used to fit the model information with the tissue surface information of the denture base. A total of 8 regions were selected in the upper and lower complete dentures, and 10 points were randomly selected in each region. The average value of the absolute deviation value(Dm) of each region was calculated. SPSS 22.0 software package was used to analyze the Dm in a total of 24 regions of the three pairs of dentures.

Results: The absolute mean deviation was (0.056±0.025) mm in the cutting group, (0.103±0.038) mm in the printing group, and (0.096±0.039) mm in the traditional group, which were significantly different among the three groups(P＜0.05). The trueness of the ablation group was better than that of the conventional group, and the difference was significant (P＜0.05). The trueness of the printing group was worse than that of the traditional group, and the difference was not significant(P＞0.05).

Conclusions: The trueness of cutting dentures is better than that of traditional dentures, while the trueness of 3D printed dentures is not significantly better than that of traditional dentures.