Position Accuracy of Implant Analogs on 3D Printed Polymer versus Conventional Dental Stone Casts Measured Using a Coordinate Measuring Machine

• Main Authors: Gonzalez-Martín, Ó (Author), Özcan, M. (Author), Pérez López, J. (Author), Revilla-León, M. (Author), Sánchez-Rubio, J.L (Author)
• Format: Article
• Language: English
• Published: Blackwell Publishing Inc. 2018
• Subjects: 3D printing; additive manufacturing technologies; comparative study; complete denture; computer aided design; Computer-Aided Design; definitive implant cast; dental impression; Dental Impression Technique; Dental Models; dental procedure; Dental Prosthesis, Implant-Supported; denture design; Denture Design; Denture, Complete; direct light processing technology; human; Humans; implant prostheses; implant-supported denture; inject technology; multijet printing; polymer; Polymers; Printing, Three-Dimensional; procedures; stereolitography technology; three dimensional printing
• Online Access: View Fulltext in Publisher

 Purpose: To compare the accuracy of implant analog positions on complete edentulous maxillary casts made of either dental stone or additive manufactured polymers using a coordinate measuring machine (CMM). Material and Methods: A completely edentulous maxillary model of a patient with 7 implant analogs was obtained. From this model, two types of casts were duplicated, namely conventional dental stone (CDS) using a custom tray impression technique after splinting (N = 5) and polymer cast using additive manufacturing based on the STL file generated. Polymer casts (N = 20; n = 5 per group) were fabricated using 4 different additive manufacturing technologies (multijet printing-MJP1, direct light processing-DLP, stereolithography-SLA, multijet printing-MJP2). CMM was used to measure the correct position of each implant, and distortion was calculated for each system at x-, y-, and z-axes. Measurements were repeated 3 times per specimen in each axis yielding a total of 546 measurements. Data were analyzed using ANOVA, Sheffé tests, and Bonferroni correction (α = 0.05). Results: Compared to CMM, the mean distortion (μm) ranged from 22.7 to 74.9, 23.4 to 49.1, and 11.0 to 85.8 in the x-, y-, and z-axes, respectively. CDS method (x-axis: 37.1; z-axis: 27.62) showed a significant difference compared to DLP on the x-axis (22.7) (p = 0.037) and to MJP1 on the z-axis (11.0) (p = 0.003). Regardless of the cast system, x-axes showed more distortion (42.6) compared to y- (34.6) and z-axes (35.97). Among additive manufacturing technologies, MJP2 presented the highest (64.3 ± 83.6), and MJP1 (21.57 ± 16.3) and DLP (27.07 ± 20.23) the lowest distortion, which was not significantly different from CDS (32.3 ± 22.73) (p > 0.05). Conclusion: For the fabrication of the definitive casts for implant prostheses, one of the multijet printing systems and direct light processing additive manufacturing technologies showed similar results to conventional dental stone. Clinical significance: Conventional dental stone casts could be accurately duplicated using some of the additive manufacturing technologies tested. © 2017 by the American College of Prosthodontists