The discovery of an iron pin in place of an upper incisor tooth from northern France may represent one of the earliest examples of a dental implant in Western Europe. The finding has appeared beside the body of a young woman buried in the third century BC, and was not sure whether was inserted to replace a fallen teeth or simply used to restore the visual integrity of the body. The fact that it had the same shape and size as the rest of the teeth hypothesizes that could be a dental prosthesis.
While the find may be the earliest dental implant known from Western Europe, prosthetic teeth dating back 5,500 years have been found in Egypt and the Near East. For more information you can go directly to their discoverers (in English) or BBC news (in English).