The Use of 3D Printing in the Fabrication of Nasal Stents

Abstract

Nasoalveolar molding of the cleft lip, nose, and alveolar palate has been a successful strategy for the restoration of oronasal function and appearance, but it has some drawbacks. The temporary implant that is inserted before surgical reconstruction is a large appliance requiring numerous adjustments, it can irritate delicate soft tissues, and interfere with the infant's ability to nurse or feed. In the early post-operative period and for months after cleft lip repair, patients wear standardized silicone stents that come in multiple sizes, but require significant sculpting to fit the unique cleft deformity. Three-dimensional (3D) printing offers the potential of highly personalized and patient-specific treatment. We developed a method that produces a customized 3D printed stent that matches the contours and unique features of each patient and permits modification and adjustments in size and shape as the patient ages. With 3D scanning technology, the device can be designed at the first visit to create an appliance that can be worn sequentially with minimal trauma, does not impede feeding, and a prosthesis that will improve compliance. The device will be worn intraorally to help shape the alveolus, lip, and nose before surgical repair. Furthermore, the stent can be doped with drugs as each patient's case warrants.

Novel Biomaterials Used in Medical 3D Printing Techniques

“…In medicine, FDM is used for fabricating customized patient-specific medical devices, such as implants, prostheses, anatomical models, and surgical guides. Various thermoplastic polymers are doped with variety of bioactive agents, including antibiotics [ 10 ], chemotherapeutics [ 11 ], hormones [ 12 ], nanoparticles [ 13 , 14 ], and other oral dosages [ 15 , 16 ] for personalized medicine. Using this technology, non-biocompatible materials, such as ABS [ 17 ] or thermoplastic polyurethane (TPU), are used for creating medical models for perioperative surgical planning and simulations [ 18 ].…”

3D-Printing of Drug-Eluting Implants: An Overview of the Current Developments Described in the Literature

“…The 3D-printed stents were coated with the water-soluble polymer PVA containing penicillin to a drug load of 1.3% ( w / w ). These successfully inhibited the growth of E. coli , similar to the stents of Mills et al [ 40 ], where the drug gentamicin sulfate (1–2.5% w / w ) was incorporated in the self-manufactured PLA filaments by HME before printing.…”

“…Typical for FDM 3D-printing, the drugs can be incorporated in the filaments while these are prepared by HME. For this purpose, the drugs are previously blended with the polymer composition or coated onto polymer pellets by using an oil casting method [ 31 , 34 , 35 , 36 , 37 , 38 , 39 , 40 , 41 , 42 , 43 , 44 ]. The drug should be homogenously dispersed in the filament for controllable drug loading of the implants because no mixing effects occur during the printing process.…”

“…With the insertion of a foreign object, the risk of infection is high [ 115 , 116 , 117 ]. In research on 3D-printed stents and catheters, attempts to manage this risk include use of antimicrobial drugs such as nitrofurantoin, gentamicin, penicillin or tetracycline [ 31 , 38 , 40 , 41 , 62 , 118 , 119 ]. Additional to the inhibition of microbial growth, tube-shaped implants have to fulfill high standards for their mechanical stability over a longer period of time [ 120 , 121 ].…”

“…Currently, many stents for support in lip and palate surgery use the concept of one-size-fits-all but Mills et al and Boyer et al worked on solutions for higher personalization using the FDM 3D-printing technique [ 40 , 62 ]. Boyer et al [ 62 ] used photogrammetry to achieve the ideal fit for patients’ contours ( Figure 2 A).…”