A simple, no-cost method for 3D printed model identification

Improving Estimation of Layer Thickness and Identification of Slicer for 3D Printing Forensics

This study emphasizes the significance of estimating the layer thickness and identifying slicer programs in the realm of 3D printing forensics. With the progress in 3D printing technology, precise estimation of the layer thickness has become crucial. However, previous research on layer thickness estimation has mainly treated the problem as a classification task, which is inadequate for continuous layer thickness parameters. Furthermore, previous studies have concentrated on hardware-based printer identification, but the identification of slicer programs through 3D objects is a vital aspect of the software domain and can provide valuable clues for 3D printing forensics. In this study, a regression-based approach utilizing a vision transformer model was proposed. Experiments conducted on the SI3DP++ dataset demonstrated that the proposed model could handle a broad range of data and outperform the current classification models. Additionally, this study proposed a new research direction by introducing slicer program identification, which significantly contributes to the field of 3D printing forensics.

Digital (R)Evolution: Open-Source Softwares for Orthodontics

Among the innovations that have changed modern orthodontics, the introduction of new digital technologies in daily clinical practice has had a major impact, in particular the use of 3D models of dental arches. The possibility for direct 3D capture of arches using intraoral scanners has brought many clinicians closer to the digital world. The digital revolution of orthodontic practice requires both hardware components and dedicated software for the analysis of STL models and all other files generated by the digital workflow. However, there are some negative aspects, including the need for the clinician and technicians to learn how to use new software. In this context, we can distinguish two main software types: dedicated software (i.e., developed by orthodontic companies) and open-source software. Dedicated software tend to have a much more user-friendly interface, and be easier to use and more intuitive, due to being designed and developed for a non-expert user, but very high rental or purchase costs are an issue. Therefore, younger clinicians with more extensive digital skills have begun to look with increasing interest at open-source software. The aim of the present study was to present and discuss some of the best-known open-source software for analysis of 3D models and the creation of orthodontic devices: Blue Sky Plan, MeshMixer, ViewBox, and Blender.

Surgical planning using facial fracture 3D models: The role of cyanoacrylate glue and miniplating for anatomical reduction

Background

In comminuted facial fractures, peri-operative use of 3D-printed life size models is increasingly a useful adjunct. It allows for preoperative surgical rehearsal and plate bending, to achieve anatomical reduction with reduced operative time and cost. One problem encountered is difficulty contouring the fixation plate whilst maintaining the relative spatial orientation of comminuted fragments. This paper shares an effective method of overcoming this problem.

Methods

All comminuted facial fracture patients underwent counselling for 3D printing. Pre-printing thresholding and segmentation of each fragment (as directed by the surgeon) were done by the radiologist and the engineering team, using the multi-slice CT Face DICOM data. Life-size 3D-resin models of the fractures were printed. Fast-acting medium consistency cyanoacrylate glue (Zap-A-Gap^Ⓡ) and miniplates were used to assemble the printed model segments in ‘anatomic reduction’. Aerosolized alcohol accelerator facilitated immediate glue curing, providing a stable model. The plates were adapted over this restored neonative 3D construct with bending inserts, sterilized and used intraoperatively. The 3D model was used to guide the operative sequence. Intraoperative CT was used in select cases to confirm anatomic reduction.

Results/Complications

All patients (n = 5) had comminuted fractures in at least one of the bony units (mandible, maxilla or orbits) and one was a pan-facial fracture case. 3D printed models aided fracture reduction and fixation, whilst avoiding the guesswork in ascertaining the contour of the mandibular arch. In addition, the pre-contoured mandible plates restored premorbid occlusion and projection, without the need for long-term archbars in all cases. Operative time was estimated to be reduced by 0.5–1 h. Resident teaching was enhanced by this approach.

Conclusion

The application of medium consistency fast-acting cyanoacrylate glue and miniplates facilitated the creation of the premorbid facial skeletal model and allowed pre-bending of the plates, thus saving operative time and cost.

[3D-assisted mandibular reconstruction: A technical note of fibula free flap with preshaped titanium plate]

The purpose of this technical note is to illustrate a simple and economical preoperative method for preshaping a reconstructive titanium plate in a fibula free flap (FFF) by using 3D printing of a virtually reconstructed mandible haptic model. The whole process consisted in creating a 3D model of the patient's mandible based on a CT-scan using a combination of free software (3Dslicer and ITK-snap), and simulating the surgical osteotomies and reconstruction, and print it as a guide for bending a reconstruction titanium plate. Reconstruction is performed using virtual cubes (1 to 3 cubes, according the number of FFF osteotomies). This virtual lab work is performed using 3D Builder® (Microsoft, Redmond) software. This technique allows obtaining an optimal plate application on the bony fragments. It facilitates reconstructive surgery with good functional (putting the patient back in an optimal dental occlusion based on the native maxilla) and aesthetic results. This technical note presents a simple and economical preoperative fabrication of a reconstructive plate through freeware and a low-cost 3D printer accessible to all surgeons.