A dental filling material comprising an inner core and outer layer of material disposed and surrounding the inner core, both the inner core and outer layer of material each containing a thermoplastic polymer. The thermoplastic polymer may be biodegradable. A bioactive substance may also be included in...http://www.google.es/patents/US7837471?utm_source=gb-gplus-sharePatente US7837471 - Dental filling materials and methods of use
