Dimensional accuracy and surface roughness of polymeric dental bridges produced by different 3D printing processes

Abstract

Purpose: To compare the dimensions accuracy and surface roughness of polymeric dental bridges produced by different 3D printers. Design/methodology/approach: Four-part dental bridges were manufactured by three printing systems working on the basis of digital light projection (DLP) stereolithography (SLA), laser-assisted SLA and fused deposition modeling (FDM). The materials used from SLA printers are liquid methacrylate photopolymer resins, while FDM printer use thin wire plastic polylactic acid. The accuracy of the external dimensions of dental bridges was evaluated and the surface roughness was measured. Findings: It was found that compared to the base model, the dimensions of the SLA printed bridges are bigger with 1.25%-6.21%, while the corresponding dimensions of the samples, made by FDM are smaller by 1.07%-4.71%, regardless the position of the object towards the substrate. The samples, produced by FDM, are characterized with the highest roughness. The average roughness deviation (Ra) values for DLP SLA and lase-assisted SLA are 2.40 μm and 2.97 μm, respectively. Research limitations/implications: For production of high quality polymeric dental constructions next research should be targeted to investigation of the polymerization degree, stresses and deformations. Practical implications: Our study shows that 3D printers, based on laser-assisted and DLP SLA, can be successfully used for manufacturing of polymeric dental bridges – temporary restorations or cast patterns, while FDM system is more suitable for training models. The results will help the dentists to make right choice of the most suitable 3D printer. Originality/value: One of the largest fixed partial dentures – four-part bridges, produced by three different commercial 3D printing systems, were investigated by comparative analysis. The paper will attract readers’ interest in the field of biomedical materials and application of new technologies in dentistry.

Three-Dimensional Evaluation on Accuracy of Conventional and Milled Gypsum Models and 3D Printed Photopolymer Models

“…Compared with DLP technology, which uses a projector to cure one layer at a time, SLA technology uses a laser beam to cure the photopolymer material from point to line and surface [37]. Thus, more complete polymerization is achieved over the overall thickness of the layer [48]. As shown in Figure 4, D3P shows relatively dark colors for all prepared teeth compared to S3P.…”

The Effect of Different Cleaning Protocols of Polymer-Based Prosthetic Materials on the Behavior of Human Gingival Fibroblasts

“…Average surface roughness values (Ra/Sa) in different studies range widely: PMMA 0.02–6.2 µm [ 18 , 19 , 20 , 21 , 52 ], 3D printed PMMA (SLA) 0.39–2.97 µm [ 52 , 53 ], PEEK 0.032–2.52 µm [ 15 , 18 , 19 , 20 , 24 , 52 , 54 , 55 ], and PEKK 0.24–3.11 µm [ 56 , 57 ]. In some of these studies, cleaning protocol is either not stated or not used after polishing [ 24 , 52 , 53 ]. Most commonly, an ultrasonic bath filled either with water or alcohol (e.g., 70% ethanol or isopropanol) with consecutive water washing was used from 3 up to 20 min [ 15 , 18 , 20 , 21 , 54 , 55 , 57 ].…”

“…Most commonly, an ultrasonic bath filled either with water or alcohol (e.g., 70% ethanol or isopropanol) with consecutive water washing was used from 3 up to 20 min [ 15 , 18 , 20 , 21 , 54 , 55 , 57 ]. There is a high degree of heterogeneity in methodology: material specifications (inorganic filler content), surface finishing protocols, and significant variation of profilometry methods [ 15 , 18 , 20 , 21 , 24 , 52 , 53 , 54 , 55 , 56 , 57 ]. The results of the current study after both cleaning protocols are in the reported range for PMMA and PEEK but are lower for 3D printed PMMA and PEKK.…”

“…The results of the current study after both cleaning protocols are in the reported range for PMMA and PEEK but are lower for 3D printed PMMA and PEKK. In other studies, PMMA was not polished after 3D printing, and its surface roughness varied depending on object orientation during 3D printing [ 53 , 58 ]. Meanwhile, PEKK abutment surfaces were roughened, and bonding strength was tested [ 56 , 57 ].…”

Cytocompatibility of 3D printed dental materials for temporary restorations on fibroblasts

“…4). This was thought to be caused by the difference in fabrication methods between DLP 3D printing and self-curing [32,33]. Therefore, research on biocompatibility regarding micro leakage of temporary restorative materials are recommended for future research.…”