Quantitative evaluation of edentulous maxillomandibular relationship record using diagnostic complete dentures fabricated by CAD and 3D printing

PURPOSE: The present study aimed to quantitatively evaluate the accuracy of the edentulous maxillomandibular relationship record for diagnostic complete dentures fabricated using computer-aided design (CAD) and three-dimensional (3D) printing. METHODS: Six edentulous patients were enrolled. The maxillomandibular relationship obtained from diagnostic complete dentures (DiaCD test group), that obtained from complete dentures with artificial teeth in the intercuspal position (CD control group), and the centric relationship acquired by gothic arch tracing (CR standard group) were recorded, and 3D surface scanning was performed on these records. Using the CR standard group as a reference, the DiaCD test and CD control group displacements were measured in the horizontal antero-posterior, horizontal right-and-left, and vertical directions. The displacements for the DiaCD test group were compared with those for the CD control group using the Wilcoxon matched-pairs signed rank test. RESULTS: In terms of centric relationship, the 95% confidence interval of displacement in the horizontal antero-posterior direction was (0.54-1.89) mm in the DiaCD test group and (0.32-1.34) mm in the CD control group. The inter-group difference was significant (P = 0.03). CONCLUSION: It is feasible to record the edentulous maxillomandibular relationship using diagnostic complete dentures fabricated by CAD/3D printing, but the protrusion of edentulous patients should not be neglected.