Titanium implants with oxidized surfaces: the background and long-termresults

Abstract

The purpose of this paper is to give an overview of different implant surfacemodification technologies—including the presentation of a new technique,involving the formation of a ceramic titanium oxide coating. Three techniques areused to modify metal surfaces: (1) addition of material, (2) removal of materialand (3) modification of material already present, e.g. by means of laser orelectron-beam thermal treatment. The new technique outlined in this paperrelates to the production of a corrosion-resistant, 2000–2500 Å thick, ceramic oxidelayer with a consistent crystalline structure on the surface of a titanium implant.The layer is grown electrochemically from the bulk of the metal and modified byheat treatment. Such ceramic oxide-coated implants have advantageous propertiescompared to implants covered with other coatings: a higher external hardness; agreater force of adhesion between the titanium and the ceramic oxidecoating; virtually perfect insulation between an organism and a metaland therefore no possibility of triggering metal allergy. Plates and screwsfor maxillofacial osteosynthesis and dental root implants with ceramicoxide coatings were subjected to various physical, chemical and electronmicroscope tests for qualitative characterization, and have been applied insurgical practice over a period of 15 years. The mini-plates removed wereexamined for the possible surface alterations which may occur during theimplantation period. The sites of the removal were inspected for metallosis, whichis common when titanium mini-plates are used. The results obtaineddemonstrate the good properties of the ceramic oxide-coated implants.