Biomedical composites dental applications

Particulate reinforcement in biomedical composites is used widely for ceramic matrices in dental and bone-analogue applications. The most common such particle form is hydroxyapatite, a natural component of bone where it exists in a composite structure with collagen. Hydroxyapatite particles have very poor mechanical properties and may serve more as a bioactive than reinforcement component. 

The past 10 years have been characterized by an explosion in the field of materials science. It cannot be denied that scientists all over the world exdted by the development of smart polymers, composites, and systems invest effort in studying them in potential biomedical appUcations. The term Smart defines a material or system having the ability of adapting itself to external stimulus by a number of ways, for example, shape shifting. The most known nonpolymer biomaterial is the shape memory alloys, such as NiTinol, with many dental applications [111]. Smart polymers are still under development [112, 113], some are already commercially available as in the case of smart polyurethanes (DiAPLEX ) by Mitsui Polymers. Recently, a cardiology product has been released in the market featuring smart characteristics. The discussion is about a cardiology stent dilated with the help of a balloon made from smart shape memory polyurethane as described in a 2002 US patent, and placed inside the blocked arteries of a patient [114]. 

We chose to modify the anhydride monomers with photopolymerizable methacrylate functionalities. Methacrylate-based polymers have a long history in biomedical applications, ranging from photocured dental composites [20] to thermally cured bone cements [21]. Furthermore, photopolymerizations provide many advantages for material handling and processing, including spatial and temporal control of the polymerization and rapid rates at ambient temperatures. Liquid or putty-like monomer/initiator... 

---