Abstract: The invention relates to a new process for obtaining tissue-protective devices of bone surgery implants prepared from a medical-purity metal, titanium and/or a titanium-base microalloy containing at least 98% by weight of titanium, by establishing a biocompatible (tissue-protective) coating on the metal surface by anodic oxidation after degreasing and chemical or electrochemical etching, which comprises carrying out the anodic oxidation of the etched implant surfaces in an aqueous solution of a phosphate concentration lower than 20% by weight with a current density of 2 to 50 mA/cm.sup.2 until reaching a voltage of at least 105 V, then, after washing to ion-free, heat-treating the thus-oxidized implants at a temperature between 120.degree. C. and 750.degree. C. for 5 to 120 minutes, and repeating once or twice the anodic oxidation and heat-treatment with the phosphate concentration, current density and temperature values as given above for the first step.