A cotyloid implant including a screwable cup receiving an articular insert. The cup is provided with screwing elements (11) on the periphery thereof and more particularly in the equatorial area (2) thereof, the elements being used to penetrate the bone material of the acetabular cup during screwing. The cup includes an osteointegration-facilitating coating such as a selective calcium hydroxyapatite coating. The coating (16) is a thick coating on the convex parts of the outer surface of the cup, including areas or valleys or hollow thread elements which are left free in the screwing elements. The coating is not as thick (17) or is even absent on raised areas or screw thread areas.