Disclosed herein are methods of forming a three-dimensional object having a biodegradable or bioerodible polymer or copolymer. In some embodiments, the methods include providing a dual cure resin with a photoinitiator, monomers and/or prepolymers that are polymerizable by exposure to actinic radiation or light, at least one cyclic ester, a ring-opening polymerization initiator, and a ring-opening polymerization catalyst. Resins useful for carrying out such methods, and products produced from such methods, are also described.
