Color Matching and Biomimicry for Multi-Material Dental 3D Printing

The growing global demand for removable partial and full dentures, driven by an aging population and the high prevalence of edentulism, emphasizes the importance of advancing manufacturing solutions. Multi-material jetting, with newly regulatory-approved dental resins, facilitates the production of monolithic, full-color dentures, reducing manual labor and enabling advanced aesthetic customization. We propose a practical method for dental layer biomimicry and multi-spot shade matching using multi-material 3D printing. It integrates seamlessly into workflows combining dental CAD tools, which compute the outer shape of dentures, and industrial multi-material slicers. We introduce a morphable star-shape descriptor to embed enamel, dentin, and root layers with controlled thicknesses into outer tooth geometries. To compute per-layer material ratios, we first present a forward model to predict the color of printed layered slabs mimicking inner tooth structures with variable translucencies. The slab design enables reasonable color predictions on layered tooth shapes. Based on the forward model, we propose a backward model to compute per-layer material ratios for given layer-translucencies to achieve color matches at multiple points on the tooth surface. The method’s effectiveness is demonstrated by fabricating various dentures with custom layers that accurately replicate VITA classical shades, showcasing its practical and versatile application in denture manufacturing.