[3D-assisted mandibular reconstruction: A technical note of fibula free flap with preshaped titanium plate]. / Reconstruction mandibulaire par lambeau fibulaire : note technique de pré-conformation de plaques d'ostéosynthèse assistée en 3D.

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.

A modified method for a customized harvest of fibula free flap in maxillofacial reconstruction.

Mandibular reconstruction using computer-aided design/computer-aided manufacturing cutting guides is currently a common procedure. However, inaccurate positioning of the cutting guide onto the fibular bone may result in osteosynthesis difficulties or imprecision in the reconstruction. A novel way to improve the stability of the cutting guides may be to add pillars in order for them to be suspended from the fibula, avoiding soft tissues interactions. We present the case of a 39-year-old male who needed mandibular reconstruction after a self-inflicted ballistic injury. We designed a customized cutting guide which included a set of 8 pillars allowing a suspension of the cutting guide 8 millimeters above the bone level. The pillars were perpendicular to one another, and allowed the operator to screw the cutting guide to the bone. The orthogonal position of the pillars enabled real stability during the osteotomies. In the operator experience, the length of the pillars was too important, and led to incomplete osteotomies, and the whole device was too bulky. However, with adaptations in the size of the pillars and the size of the whole device, this solution could be useful in cutting guide design to avoid impairments due to the soft tissues surrounding the fibula.

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

3D printed models are often very similar in shape and can be inadvertently switched if the related patient is not identified correctly. Here, we present a free and simple method to imprint letters and numbers in a 3D model. CT scan data were used to create an STL file of a patient's mandible. We then used Blender software to modify it with numbers and letters. We chose to imprint a series of four letters and numbers on our 3D models. We chose representative letters and numbers of the Latin alphabet. Six models were printed with an Up plus 2 - easy 120 3D printer with different character sizes and shape to evaluate the readability. All models were printed without any failures. Regarding readability, 2 mistakes were made among ten readers. The favourite extrusion depth was 3 mm, and the largest model was preferred. Identification can be done at different times and by different means, but identifying the 3D model during its creation is safer. Moreover these identified 3D models could be saved in the digital patient medical file. The identification location should take into consideration the future indication of the 3D printed medical model. We recommend that 3D identification should be done using at least 7.5mm high, with a depth of 3mm. Our method allows easy, fast and free 3D text. This 3D text identification printing method may be a first step towards the legal use of 3D printed models made within the hospital.

How to produce pre-shaped rigid arch bars using low-cost 3D printing technology - A technical note.

Numerous oral and maxillofacial procedures in dentate patients begin with the fixation of occlusions. While several techniques exist to perform mandibulo-maxillary fixation, many surgeons use arch bars in common practice. In cases of severe craniofacial traumas or jaw malformations, such as temporomandibular joint ankylosis, it may be impossible to use rigid arch bars. This technical note reports on the development of a technique to produce pre-shaped rigid arch bars using 3D printing technology. We take the case of a patient who presents Le Fort 1, Le Fort 2 and Le Fort 3 fractures as well as a central palatine disjunction, an angular mandibular fracture and bilateral zygomatic fractures. We specify the indications and limitations of this technique.