Bone loss often shows up as a black space on a dental x-ray. The amount of bone loss determines how much space is shown. On a normal x-ray, the bone and gums will be level with the bottom of the teeth, between the crown and the root. A very small amount of black space may be present, but this typically does not indicate bone loss. When there is a large amount of black space and the bone and gum line is below the bottom of the tooth and in line with the root of the tooth, this indicates significant bone loss. In some cases of very severe bone loss, the black space on a dental x-ray will extend beyond the roots of the tooth and potentially even below them. For patients with bone loss indicated by black space on an x-ray, bone grafting may be recommended, especially in cases where a dental implant is being considered.