Photopolymerizable Biopolymers for Rapid Prototyping of Cellular Bone Replacement Materials

The disadvantages of materials, which are currently used in orthopaedic surgery have led to the development of new synthetic biocompatible and biodegradable materials. Rapid Prototyping offers the possibility to fabricate cellular structures with nearly arbitrary form and structures out of photocurable liquid acrylate-based formulations by radical polymerization. Such a composition consists of biodegradable multifunctional monomers that can be cleaved in vivo. To adjust the network density reactive diluents are used. Soluble filler materials are applied to tune the viscosity for an optimum resolution of the stereolithographic shaping process. Adequate photoinitiators as well as fillers for advanced mechanical properties are also required. In the present investigations, as a first step, we aim at the development of such photopolymerizable formulations for cellular implants which can be printed directly by stereolithography. In this paper we discuss the selection and evaluation of different monoand multifunctional reactive diluents regarding the photoreactivity, mechanical properties and support for proliferation of osteoblast like cells.