Trueness of 3D printed partial denture frameworks: build orientations and support structure density parameters

Abstract

PURPOSE The purpose of the study was to assess the influence of build orientations and density of support structures on the trueness of the 3D printed removable partial denture (RPD) frameworks. MATERIALS AND METHODS A maxillary Kennedy class III and mandibular class I casts were 3D scanned and used to design and produce two 3D virtual models of RPD frameworks. Using digital light processing (DLP) 3D printing, 47 RPD frameworks were fabricated at 3 different build orientations (100, 135 and 150-degree angles) and 2 support structure densities. All frameworks were scanned and 3D compared to the original virtual RPD models by metrology software to check 3D deviations quantitatively and qualitatively. The accuracy data were statistically analyzed using one-way ANOVA for build orientation comparison and independent sample t-test for structure density comparison at (α = .05). Points study analysis targeting RPD components and representative color maps were also studied. RESULTS The build orientation of 135-degree angle of the maxillary frameworks showed the lowest deviation at the clasp arms of tooth 26 of the 135-degree angle group. The mandibular frameworks with 150-degree angle build orientation showed the least deviation at the rest on tooth 44 and the arm of the I-bar clasp of tooth 45. No significant difference was seen between different support structure densities. CONCLUSION Build orientation had an influence on the accuracy of the frameworks, especially at a 135-degree angle of maxillary design and 150-degree of mandibular design. The difference in the support’s density structure revealed no considerable effect on the accuracy.

Evaluation of the Influence of Build Orientation on the Surface Roughness and Flexural Strength of 3D-Printed Denture Base Resin and Its Comparison with CAD-CAM Milled Denture Base Resin

“…Based on the results of our study, the 120-degree angle demonstrated less surface roughness than the 135-degree angle, which confirms the influence of the build orientation. 24,25 However, the difference between them was not statistically significant to recommend one build orientation over the other. These findings could be attributed to the simplicity of the specimen shape configuration used in this study, and may reflect different results if an actual denture print was to be considered.…”

“…The specimens were subjected to post-processing curing for 20 minutes in an Asiga Flash post-curing chamber (ASIGA, Sydney, Australia) following which all the supports were removed. 25 The printed specimens were measured (65 Â 10 Â 3.3 mm) first by the same operator to ensure standardization and then finished using silicon carbide (mega-Schmirgelleinen; megadental, Büdingen, Germany) followed by acrylic polishing burs (Shofu Dental Corporation, San Marcos, California, United States), pumice (Kemdent Works, Wiltshire, United Kingdom) and high shine polishing compound (Keystone Industries, New Jersey, United States).…”

“…The specimens were subjected to post-processing curing for 20 minutes in an Asiga Flash post-curing chamber (ASIGA, Sydney, Australia) following which all the supports were removed. 25…”

Effect of Palatal Vault Depth on the Trueness of Metal Laser‐Sintered and Cast Cobalt‐Chromium Removable Partial Denture Frameworks

“…The framework can be created on a three-dimensional (3D) model created from 3D scans of the working cast by utilizing this technology. 5 The duties of a dental surveyor (identifying insertion and removal directions, outlining the framework design, blocking out the working cast, applying for relief, and finalizing the wax-up of the framework) can now be accomplished digitally. This digitization speeds up the fabrication procedures, lowers material costs, and minimizes time by reducing the necessity for several impressions and refractory casts that traditional casting requires.…”

“…Using computer‐aided design and computer‐aided manufacturing (CAD‐CAM) innovations in metal frameworks fabrication for removable partial dentures is increasing. The framework can be created on a three‐dimensional (3D) model created from 3D scans of the working cast by utilizing this technology 5 . The duties of a dental surveyor (identifying insertion and removal directions, outlining the framework design, blocking out the working cast, applying for relief, and finalizing the wax‐up of the framework) can now be accomplished digitally.…”