The invention includes biostructures which may be characterized as having substantially all of the organic-solvent-soluble material in the form of a network of irregularly shaped perforated films. The biostructure may further include particles of a substantially-insoluble material, which may be a member of the calcium phosphate family. The biostructure may be osteoconductive. The biostructure may further contain an Active Pharmaceutical Ingredient or other bioactive substance. The API may be a substance which stimulates the production of bone morphogenetic protein, such as Lovastatin or related substances, thereby making the biostructure effectively osteoinductive. One or more of the polymers may have a resorption rate in the human body such as to control the release of the API. Methods of manufacture are also disclosed.