Ph.D. candidate in Bioingegneria E Scienze Medico-chirurgiche , 39th cycle (2023-2026)
Department of Mechanical and Aerospace Engineering (DIMEAS)
Profile
PhD
Research topic
3D PRINTING OF CLEAR ALIGNERS MADE OF BIOPOLYMERS
Tutors
- Nicola Scotti
- Bartolomeo Coppola
Research presentation
Research interests
Biography
The aim of my phd is to design a biocompatible resin formulation that is both biobased and biodegradable to be used for CAT 3D printing.
In particular, the focus of my research is on the development of bio-based resins for 3D printing using vat-photopolymerization. This method consists of a layer-by-layer curing of liquid photopolymer resins into parts with precisely controlled geometry.
Digital Light Processing (DLP) is the primary technique in this field. However, one of the main issues is the large carbon footprint associated with commercially available photopolymer resins, which are typically based on epoxides and acrylates derived from fossil resources, and also their negative impact on health. Moreover, photopolymerization results in thermosetting products that are inherently non-recyclable or non-biodegradable due to their crosslinked macromolecular structure, which creates serious waste management challenges, given the growing demand for materials in additive manufacturing (AM).
More recently, numerous authors started to investigate the use of bio-based and biodegradable resins for aligners but not for DLP technology.
With technological advancements, the next paradigm shift would likely involve direct 3D printing of aligners from digital designs.
The advantages of using a clear aligner that is 3D printed are not just limited to the reduction of the cumulative errors introduced from the analog impression, intraoral scan, 3D printed physical model, and the subsequent thermoplastic process. In addition to improved accuracy, 3D printing can shorten the supply chains, lower costs, and lead to a more sustainable process by generating less waste. Theoretically, 3D direct printing allows the fabrication of clear aligners with customized thickness and spatial control of aligner thickness across the arch. The thickness of the aligner and the material chosen influence not only the magnitude of force delivered to teeth but also the mechanical properties of the aligners as well
The only aligner 3d printing resin for aligners currently on the market is Tera Harz TC-85 (Graphy Inc., Seoul, South Korea). It is a photopolymer material introduced by Graphy to overcome the current limitation of thermoforming sheet type aligners and the Tera Harz direct aligner can be 3D printed directly with a 3D printer