Dimensional Printing Research Articles

3D Printing of Naturally Derived Adhesive Hemostatic Sponge.

Hydrogel hemostatic sponges have been recognized for its effectiveness in wound treatment due to its excellent biocompatibility, degradability, as well as multi-facet functionalities. Current research focuses on optimizing the composition and structure of the sponge to enhance its therapeutic effectiveness. Here, we propose an adhesive hydrogel made from purely natural substances extracted from okra and Panax notoginseng. We utilize 3-dimensional (3D) printing technology to fabricate the hemostatic hydrogel scaffold, incorporating gelatin into the hydrogel and refining the mixing ratio. The interaction between gelatin and okra polyphenols contributes to successful injectability as well as stability of the printed scaffold. The okra in the scaffold exhibits favorable adhesion and hemostatic effects, and the total saponins of Panax notoginseng facilitate angiogenesis. Through invitro experiments, we have substantiated the scaffold's excellent stability, adhesion, biocompatibility, and angiogenesis-promoting ability. Furthermore, invivo experiments have demonstrated its dual functionality in rapid hemostasis and wound repair. These features suggest that the 3D-printed, natural substance-derived hydrogel scaffolds have valuable potential in wound healing and related applications.

Cost-effective office 3D printing process in orthopaedics and its benefits: A case presentation and literature review

Background and objectives The advent of 3-Dimensional (3D) printing technology is one of the most revolutionising breakthroughs of the generation. Its benefits in surgical practice are undeniable, however a steep learning curve and concerns regarding costs may pose a barrier to large scale implementation. Methods We set up an in-house 3D printing facility in our institution and described our workflow. Using the described workflow, we 3D printed models which were used in the surgical management of three patients with differing conditions. Results We present three case examples to display the uses that 3D printing technology is able to provide in our experience, and show how 3D printing technology can be beneficial in the field of orthopaedic oncology and surgically complex cases. 3D printing has proven to be useful and improved quality of care in these case examples. The processes for each case were described individually. The benefits of our in-house 3D printing facility were discussed in detail. Conclusion An in-house office 3D printing facility is advantageous and cost-efficient. Its benefits can be maximised if implemented on a larger scale and has the potential to be standard of care in many institutions.

Design and development of 3D printed shape memory triphasic polymer-ceramic bioactive scaffolds for bone tissue engineering.

Scaffolds for bone tissue engineering require considerable mechanical strength to repair damaged bone defects. In this study, we designed and developed mechanically competent composite shape memory triphasic bone scaffolds using fused filament fabrication (FFF) three dimensional (3D) printing. Wollastonite particles (WP) were incorporated into the poly lactic acid (PLA)/polycaprolactone (PCL) matrix as a reinforcing agent (up to 40 wt%) to harness osteoconductive and load-bearing properties from the 3D printed scaffolds. PCL as a minor phase (20 wt%) was added to enhance the toughening effect and induce the shape memory effect in the triphasic composite scaffolds. The 3D-printed composite scaffolds were studied for morphological, thermal, and mechanical properties, in vitro degradation, biocompatibility, and shape memory behaviour. The composite scaffold had interconnected pores of 550 μm, porosity of more than 50%, and appreciable compressive strength (∼50 MPa), which was over 90% greater than that of the pristine PLA scaffolds. The flexural strength was improved by 140% for 40 wt% of WP loading. The inclusion of WP did not affect the thermal property of the scaffolds; however, the inclusion of PCL reduced the thermal stability. An accelerated in vitro degradation was observed for WP incorporated composite scaffolds compared to pristine PLA scaffolds. The inclusion of WP improved the hydrophilic property of the scaffolds, and the result was significant for 40 wt% WP incorporated composite scaffolds having a water contact angle of 49.61°. The triphasic scaffold exhibited excellent shape recovery properties with a shape recovery ratio of ∼84%. These scaffolds were studied for their protein adsorption, cell proliferation, and bone mineralization potential. The incorporation of WP reduced the protein adsorption capacity of the composite scaffolds. The scaffold did not leach any toxic substance and demonstrated good cell viability, indicating its biocompatibility and growth-promoting behavior. The osteogenic potential of the WP incorporated scaffolds was observed in MC3T3-E1 cells, revealing early mineralization in pre-osteoblast cells cultured in different WP incorporated composite scaffolds. These results suggest that 3D-printed WP reinforced PLA/PCL composite bioactive scaffolds are promising for load bearing bone defect repair.

Evaluation of the Marginal Fit and Fracture Resistance of Polyetheretherketone (PEEK) and Zirconia Copings: An In-vitro Study

Introduction: In dentistry, there has been an increasing demand for aesthetics and biocompatible restorations with low plaque affinity. The success of any restoration is based on three main factors: marginal fit, fracture resistance, and aesthetics. Polyetheretherketone (PEEK) is a polymeric material that has emerged as a novel thermoplastic material with wide applications. Aim: To evaluate the marginal fit and fracture resistance of PEEK and zirconia copings fabricated using Computer-aided Design (CAD)/Computer-aided Manufacturing (CAM) technology. Materials and Methods: The present in-vitro study was conducted in the Department of Prosthodontics, MM College of Dental Sciences and Research, Mullana, Ambala, Haryana, India, from November 2022 to March 2024. The present study compared the marginal fit and fracture resistance of PEEK and zirconia copings fabricated using CAD/CAM technology. All-ceramic tooth preparations were performed on extracted maxillary first premolars, and the prepared teeth were scanned. Using three dimensional (3D) printing technology, 20 resin dies were obtained. These dies were divided into two groups: 10 for PEEK and 10 for zirconia. Ten copings for zirconia and PEEK were fabricated using CAD/CAM technology, and two reference points were marked on the copings. The copings were luted with resin cement on the dies, and marginal fit and fracture resistance were recorded. The observations were statistically analysed using a two-way Analysis of Variance (ANOVA) test and a two-sample t-test. Results: The lowest mean marginal discrepancy values (18.469±6.55 μm for the palatal aspect and 17.116±6.34 μm for the buccal aspect) were observed for the zirconia copings. These values were significantly better compared to the PEEK copings (23.941±7.73 μm on the palatal aspect and 22.338±7.89 μm on the buccal aspect). In terms of fracture resistance, PEEK copings demonstrated a higher load-bearing capacity (523.11±117.27 N) and significantly better results compared to zirconia copings (395.4±150.93 N). Conclusion: The results revealed that, when comparing both PEEK and zirconia copings, zirconia copings demonstrated a better marginal fit compared to PEEK copings. However, for fracture resistance analysis, PEEK copings exhibited better load-bearing capacity than zirconia copings.

Adhesion performance of alkali-activated material for 3-dimensional printing of tunnel linings at different temperatures

Adhesion performance of alkali-activated material for 3-dimensional printing of tunnel linings at different temperatures

Experimental and statistical investigation of the surface quality of 3D printed products using STH filament material

Three dimensional (3D) printers have entered every aspect of our lives. Especially home users use 3D printers in many projects within the scope of do-it-yourself (DIY) projects. In addition, as a control mechanism in the transition from design to production, especially in areas such as prototyping, it almost eliminates the margin of error. However, the types of raw materials that can be used in 3D printing processes are relatively limited compared to other production methods. Features such as suitability for production in layers and rapid solidification come to the fore. Additionally, cooling deformations such as shrinkage also reduce the variety of materials that can be used. ABS, which is the most commonly used thermoplastic material, is also used in 3D printers. However, since ABS material has high cooling deformations such as shrinkage in production, errors occur frequently. This makes the use of the material difficult. In addition, the gases released during production cause discomfort to people. For this reason, PLA material was developed as a biomaterial based on corn starch. Easy to produce, shrinkage and cooling errors are almost non-existent. It is environmentally friendly and there is no gas released during production. However, when using PLA material, certain properties of the products such as abrasion, thermal resistance and hardness are weak in meeting the needs. For this reason, STH filament material was introduced to the market with the aim of developing a material with high thermal stability like ABS and easy to produce like PLA. Just like PLA, STH filament material is also a biomaterial and was developed for industrial use. Compared to ABS material, it is more resistant to impact environments and its thermal resistance is approximately twice that of PLA material. For this reason, in our study, parameter optimization was carried out to optimize the surface quality of 3D printed products using STH material. Layer thickness (0.15 - 0.25 mm), printing speed (60 - 100 mm/s) and extrusion width (0.35 - 0.45 mm) were preferred as variable parameters affecting the surface quality. An experimental setup consisting of 20 experiments was created using the Response Surface Method (RSM), keeping all other parameters constant. The printed 25x25x25 mm cube samples were subjected to surface roughness measurement in 3 axes. According to the results, as a result of statistical calculations, the impact ratios of the effective parameters and the most effective production parameters were estimated.

Preliminary Study of a Degenerated Tricuspid Bioprosthetic Valve Implanted via Transcatheter Valve-in-Valve Implantation Guided by 3-Dimensional Printing

BackgroundThe procedures of transcatheter tricuspid valve-in-valve (TTViV) replacement are challenging, and the clinical outcomes are still unclear. Our goal was to report the short- and mid-term clinical outcomes of patients who underwent a TTViV implantation guided by 3-dimensional (3D) printing. MethodsA retrospective analysis was performed on 6 patients who had TTViV implantation from May 2021 to March 2022. The median age was 51 years (range: 18-71 years), and 50.0% of the patients were male. Imaging assessments and 3D printing were performed on all 6 patients before the procedures. The perioperative data were evaluated, and the patients were followed up. ResultsAmong the 6 patients, the etiologies of conditions affecting the tricuspid valves at baseline varied widely, including 1 case of Ebstein anomaly, 2 cases of infective endocarditis, 1 case of ventricular septal defect, and 2 cases of rheumatic heart disease. TTViV implantation was successfully performed in all 6 patients via the femoral vein approach; postoperative tricuspid regurgitation disappeared immediately, and the hemodynamic results were satisfactory. During the follow-up, all patients had significant improvement in symptoms and functional status. ConclusionsTTViV implantation for the treatment of degenerated tricuspid bioprostheses should be considered safe and effective. Multimodal imaging and 3D printing may provide effective guidance for conducting the procedure. Clinical Trial RegistrationClinicalTrials.gov Protocol Registration System (NCT02917980).

Three dimensional printed biofilms: Fabrication, design and future biomedical and environmental applications.

Three dimensional printing has emerged as a widely acceptable strategy for the fabrication of mammalian cell laden constructs with complex microenvironments for tissue engineering and regenerative medicine. More recently 3D printed living materials containing microorganisms have been developed and matured into living biofilms. The potential for engineered 3D biofilms as invitro models for biomedical applications, such as antimicrobial susceptibility testing, and environmental applications, such as bioleaching, bioremediation, and wastewater purification, is extensive but the need for an in-depth understanding of the structure-function relationship between the complex construct and the microorganism response still exists. This review discusses 3D printing fabrication methods for engineered biofilms with specific structural features. Next, it highlights the importance of bioink compositions and 3D bioarchitecture design. Finally, a brief overview of current and potential applications of 3D printed biofilms in environmental and biomedical fields is discussed.

Letter to the Editor Regarding “Changes of Resection Goal after Using 3-Dimensional Printing Brain Tumor Model for Presurgical Planning”

Letter to the Editor Regarding “Changes of Resection Goal after Using 3-Dimensional Printing Brain Tumor Model for Presurgical Planning”

Evaluation of photopolymer resins for dental prosthetics fabricated via the stereolithography process at different polymerization temperatures. Part II: Dimensional accuracy and fracture load of fixed dental prostheses

Prostheses printed on a 3-dimensional (3D) printer need to undergo the postpolymerization process, which can increase the working time. However, it has been not suggested for reducing workload and improving the properties of prostheses in dental clinical practice. The purpose of this in vitro study was to evaluate how the printing temperature impacts the dimensional accuracy and fracture load of 3D printed fixed dental prostheses (FDPs). Dental prostheses were printed at room temperature (RT), 50°C, and 70°C using a stereolithography 3D printer. Subsequently, after rinsing away residual monomer, the printed parts underwent the green condition (it was not subjected to any postprocessing) and postpolymerization. The mechanical properties of the printed FDPs were determined by loading to fracture (n=6). To evaluate their clinical applicability, the dimensional accuracy and fit of FDPs fabricated at various resin polymerization temperatures were measured (n=6). The 1-way analysis of variance was used to perform statistical comparisons, followed by the Tukey honestly significant difference test (α=.05). The specimens printed at RT and 50°C were better than those printed at 70°C in terms of dimensional accuracy and fit (P<.05). Nonetheless, the dimensional accuracy and fit of the specimens printed at 70°C were clinically acceptable. The fracture load of the 3-unit FDPs depended significantly on the printing temperature. The dimensional accuracy and fracture load of the 70°C group were acceptable for FDP fabrication. Thus, the temperature of 70°C without postprocessing may help make the procedure more efficient.

3D printing technology to produce intraoral stents for head and neck radiotherapy: A scoping review.

Radiotherapy remains one of the main treatments for head and neck cancer; however, it is accompanied by acute and chronic adverse effects. Use of three-dimensional (3D) oral stents to modulate radiation intensity to specific target areas have been developed to minimize these adverse effects. This study aimed to present a scoping review of studies published on 3D printing of oral stents and their clinical applicability. MEDLINE/Pubmed, Scopus, Web of Science and CENTRAL Cochrane data bases were searched, studies selected, and data collected by three independent reviewers up to December 2022. The review was conducted based on the Preferred Reporting Items for Systematic Reviews and Meta-analysis-Extension for Scoping Reviews (PRISMA-ScR). The search resulted in 404 studies and 5 articles fulfilled the eligibility criteria and were considered for this review. Three-dimensional printed intraoral stents were produced for 56 patients with indication for radiotherapy. 3D-printed stents were well-tolerated by all tested patients and demonstrated great reproducibility of maxillomandibular relation, required less time for production and lower cost to manufacture. Two studies showed great protection of healthy tissues with 3D-printed stents during radiotherapy. Three-dimensional printing is promising for production of intraoral stents, however, more studies are needed to improve the technique and further investigate the safety and prevention of oral toxicities from radiotherapy.

Digital denture scanning and 3D printing for residents in care homes: A feasibility study for pre-empting denture loss.

The aim of this study was to assess the feasibility of digitally scanning dentures and 3D printing replica dentures for care home residents. The study also investigated whether the process and replacement denture was acceptable to the resident. Denture loss is a significant issue for people living in care homes and impacts on nutrition, quality of life and dignity. Denture loss is underreported, and care home residents have barriers to accessing dental care. The conventional process for remaking a denture can often take approximately 2 months with multiple clinical stages, often not feasible in adults with frailty and cognitive impairment. Scanning and 3D (3 dimensional) printing are increasingly used in dentistry, this rapidly evolving technology may provide an innovative solution to denture loss. A digital workflow was established using a handheld scanner and 3D printing technology. Care home residents wearing functional acrylic dentures were recruited. Dentures were scanned within the care home, and the scan was sent to a dental laboratory for 3D printing. The dentures were fitted at a subsequent visit, and semi-structured interviews were undertaken with the resident. Using thematic analysis, the feasibility of this pathway was assessed, and the use of digital scanning technology was explored. Eight residents successfully had dentures scanned and replicated to a satisfactory standard. It took, on average, 10 minutes to scan a denture and 20 minutes to print the denture. All replica dentures were satisfactory to the resident. Qualitative data from semi-structured interviews showed that study participants were satisfied with denture replacements and the process. The 3 main themes that emerged were: the significance of dentures to the individual, satisfaction with the scanning process and general low self-esteem and fatigue. This study has established a workflow for digitally storing dentures and replicating them satisfactorily. In the context of a care home setting, a scan of a denture can be used to provide a replacement denture if lost or broken. A large-scale study could follow now that the feasibility of this pathway has been demonstrated.

3D biomimetic scaffold’s dimensional accuracy: a crucial geometrical response for bone tissue engineering

Abstract Additive manufacturing has emerged as a trending methodology for producing different simple to complex geometries in minimum lead time, which in turn gives better quality attributes when compared to conventional manufacturing procedures. Fabrication of polylactic acid-based porous scaffold prototypes by 3-dimensional printing has been extensively performed successfully by many researchers. The dimensional accuracy of the 3-dimensional printed part is a very crucial aspect of bone tissue engineering. Dimensional precision of 3-dimensional biomimetic scaffolds has been a response characteristic somehow less focused on by researchers, though it is essential as it acts as a stereotype for defect recuperation while consequently developing extracellular matrix and bone regeneration. The present paper fosters re-tuning the process parameters of a fused deposition modeling based 3-dimensional printer while considering the dimensional precision as a response parameter by the Taguchi optimization technique using a full factorial design L27 orthogonal array set of design of experiments. The crystallinity of the polylactic acid filament material was assessed using differential scanning calorimetry and X-ray diffraction. The thermal breakdown of filament material was investigated utilizing a thermogravimetric analyzer. According to Taguchi’s signal-to-noise ratios, the optimum values were 0.14 mm of layer thickness, 20 mm s−1 of printing speed, and 80 % of infill percentage. In order to justify the results, response surface methodology was employed. R-square values for Taguchi and the response surface models were 88.61 % and 68.71 %, respectively.

Direct ink writing of Ni structures for electrocatalytic water splitting applications

Fabrication of functional metallic materials with complex shapes and fine features remains a challenge despite the advancement of various manufacturing techniques including conventional and advanced methods. Direct ink writing (DIW) is a promising 3-dimensional printing (3DP) technique that overcomes the major challenge of fabricating highly porous complex structures. Herein, we demonstrate the potential of synthesizing pure Ni structures with tailorable microstructure and geometries for functional applications, such as water-splitting and electrocatalysis, based on oxygen evolution reaction (OER) through DIW. A reduction of 3D printed NiO complex scaffolds during heat treatments yields porous or highly dense 3D Ni-meshes. The highest electrochemical surface area (ECSA) was achieved by the 3D Ni-mesh electrode with a heat treatment of 600°C-1h which leads to the best OER performance of 222 mV at a current density of 10 mA cm−2. With great stability at 1.58V for 60 h and tailorable structures, the porous 3D Ni-mesh electrode demonstrates promising water-splitting application on an industrial scale.

Marginal Adaptation and Fracture Resistance of 3D Printed and CAD/CAM Milled Definitive Resin Matrix Ceramic Crowns.

To evaluate and compare the marginal adaptation and fracture resistance of resin matrix ceramic crowns fabricated using 3-dimensional (3D) printing and computer aided design/computer aided manufacturing (CAD/CAM) milling technology. Thirty extracted human maxillary first premolars were prepared to receive crown restorations and grouped into 3 groups according to 3 different crown materials (n = 10): VE: teeth restored with milled Vita Enamic, CS: teeth restored with milled Cerasmart 270 and VSC: teeth restored with 3D-printed VarseoSmile Crown Plus. Marginal analysis was performed with the aid of a digital microscope at (230x) magnification, both before and after cementation with self-adhesive resin cement and analyzed with Image J analysis software. The fracture loads for each sample were then recorded using a universal testing machine in a single load-to-failure test up until the crowns failed. The lowest marginal gap values were recorded for VSC before (8.03 μm) and after (15.07 μm) cementation with significant difference compared to the other crown materials (p <0.05), while the differences between the milled groups were non-significant both before, (CS (11.35 μm) and VE (11.86 μm)), and after cementation, (CS (20.01 μm) and VE (21.08 μm)). In terms of fracture resistance, VE recorded significantly lower fracture load values (727.8 N) (p <0.05) than the crowns fabricated from CS (1213.8 N) and VSC (1181.5 N), which showed no statistically significant differences between each other. 3D printed definitive crowns outperformed CAD/CAM milled crowns in terms of marginal adaptation, along with comparable fracture resistance values.

Optimizing continuous emulsification with 3D printing

Multiphase processes are important in a wide range of industries including foods, pharmaceuticals, and consumer packaged goods. Improvement of these operations is challenging because of the complex hydrodynamics of the processing unit. We approached intensification of emulsification operations using continuous processing and hydrodynamic optimization with computer aided design and three dimensional printing (3dP) of fixed bed (FB) unit operations. We built and tested the emulsification capability of 3dPFB to establish key relationships among digital design variables, such as surface to volume ratio of the 3dPFB, 3.3≤s×10−4≤9.0m−1, and process performance metrics, such as drop size distribution (23.1±5.7<DSD<125.7±33.2μm). We showed that the emulsification performance can be designed a priori and demonstrated gradient 3dPFB design and complex emulsification to further establish the digital basis of design-property relationships and capabilities of 3dPFB in multiphase unit operations.

A feasibility study of several 3D printing methods for applications in epilepsy surgery.

To describe the process of 3-dimensional printing in epilepsy surgery using three different methods: Low-Force Stereolithography (SLA), Filament-Deposition Modeling (FDM), and Polyjet Stratasys, while comparing them in terms of printing efficiency, cost, and clinical utility.,MRI and CT images of patient anatomy have been limited to review in the 2-dimensional plane, which provides only partial representation of intricate intracranial structures. There has been growing interest in 3D printing of physical models of this complex anatomy to be used as an educational tool and for surgical visualization. One specific application is in epilepsy surgery where there are challenges in visualizing complex intracranial anatomy in relation to implanted surgical tools. MRI and CT data from patients with refractory epilepsy from a single center that underwent surgery are converted into 3D volumes, or stereolithography files. These were then printed using three popular 3D printing methods: SLA, FDM, and Polyjet. Faculty were surveyed on the impact of 3D modeling on the surgical planning process. All three methods generated physical models with an increasing degree of resolution, transparency, and clinical utility directly related to cost of production and accurate representation of anatomy. Polyjet models were the most transparent and clearly represented intricate implanted electrodes but had the highest associated cost. FDM produced relatively inexpensive models that, however, were nearly completely opaque, limiting clinical utility. SLA produced economical and highly transparent models but was limited by single material capacity. Three-dimensional printing of patient-specific anatomy is feasible with a variety of printing methods. The clinical utility of lower-cost methods is limited by model transparency and lack of multi-material overlay respectively. Polyjet successfully generated transparent models with high resolution of internal structures but is cost prohibitive. Further research needs to be done to explore cost-saving methods of modeling.

Three-Dimensional Printed Poly (Lactic-co-Glycolic Acid)-Magnesium Composite Scaffolds for the Promotion of Osteogenesis Through Immunoregulation.

Scaffolds play an important role in bone tissue engineering. The ideal engineered scaffold needs to be biocompatible, bioactive, and able to regulate immune cells to enhance bone regeneration. In this study, magnesium (Mg)-contained poly(lactic-co-glycolic acid) (PLGA) scaffolds (hereinafter, referred to as PLGA-2Mg) were fabricated by 3-dimensional printing using a mixture of PLGA and MgSO 4 powder. Poly(lactic-co-glycolic acid) scaffolds (hereinafter, referred to as PLGA) were also fabricated by 3-dimensional printing and were used as control. The biocompatibility, immunoregulatory ability, and osteogenic properties of PLGA-2Mg were analyzed and compared with those of PLGA. The results indicate that the incorporation of Mg increased the Young modulus and surface roughness of the scaffold, but did not affect its degradation. The PLGA-2Mg further promoted the adhesion and proliferation of MC3T3-E1 cells compared with PLGA, which indicates its improved biocompatibility and bioactivity. In addition, PLGA-2Mg inhibited the polarization of RAW 264.7 cells toward the M1 phenotype by down-regulating the IL-1β , IL-6 , and iNOs gene expression when challenged with lipopolysaccharide stimulation. In contrast, it promoted the polarization of RAW 264.7 cells toward the M2 phenotype by up-regulating the TGF-β , IL-10 , and Arg-1 gene expression without lipopolysaccharide stimulation. Finally, MC3T3-E1 cells were cocultured with RAW 264.7 cells and scaffolds using a transwell system. It was found that the expression level of osteogenic-related genes ( ALP , COL-1 , BMP2 , and BSP ) was significantly upregulated in the PLGA-2Mg group compared with that in the PLGA group. Consequently, PLGA-2Mg with increased biocompatibility and bioactivity can promote osteogenesis through immunoregulation and has the potential to be used as a novel scaffold in bone tissue engineering.

A Novel Immobilization Method for the Treatment of Head and Neck Cancer Using 3D Printing

Proper immobilization is critical for the delivery of high-quality radiation therapy. In cases when traditional immobilization is not feasible, 3-dimensional (3D) printing may provide a better-tolerated custom immobilization that is comparably effective. We present the successful treatment of a patient with inoperable oropharyngeal squamous cell carcinoma who was unable to tolerate traditional immobilization. To avoid covering the face, we created a 3D-printed cradle for the back of his head and neck. This design enabled the patient to tolerate traditional simulation scans with and without intravenous contrast and was subsequently able to undergo volumetric modulated arc therapy treatment. He successfully underwent treatment without evidence of disease more than 2 years after completion. The effect of 3D printing within the context of radiation oncology, as well as in other specialties, will undoubtedly continue to increase the variety of treatment options available to patients.

A comparison of the shear bond strength between denture teeth and denture base resins manufactured either conventionally or with a 3D printer

Statement of problemLimited information is available on the shear bond strength (SBS) between denture teeth and denture base resins fabricated using a stereolithography (SLA) 3-dimensional (3D) printer. PurposeThe purpose of this in vitro study was to evaluate the SBS between denture teeth and the denture base resins produced with the conventional method and with a 3D printer. Material and methodsConventional or 3D printed denture teeth were included in the study. The denture base resins were manufactured either conventionally or with a 3D printer. Four subgroups were tested: conventional teeth-conventional base resin (CT-CB), conventional teeth-printed base resin (CT-PB), printed teeth-conventional base resin (PT-CB), and printed teeth-printed base resin (PT-PB). The maxillary molars were combined with Ø5×2.5-mm-cylindrical denture base resin. Shear bond testing was performed by applying a parallel force to the denture teeth-denture base resin interface by using a blade-edge chisel with a crosshead speed of 1 mm/min until failure occurred. SBS and elastic modulus (EM) were recorded. One-way ANOVA followed by the Dunnett T3 post hoc test was used for the statistical analysis (α=.05). The failure modes of the specimens were also analyzed. ResultsA statistically significant difference (P<.05) was found between the evaluated groups for the SBS and EM values. PT-PB showed the highest SBS value (15.4 ±2.7 MPa), and CT-PB showed the lowest (0.9 ±0.7 MPa). The PT-CB group showed the highest EM value (62.74 ±20.80 GPa), and the CT-PB group showed the lowest (29.46 ±28.40 GPa). The CT-CB and CT-PB specimens showed mostly adhesive failure; none of the PT-PB specimens showed adhesive failure. ConclusionsThree-dimensional printing led to a better bond between the denture teeth and the denture base resin compared with the conventional method. Although these findings need to be supported by clinical studies, the use of 3D printers is appropriate in the production of denture teeth and denture bases.