In many cases, whether because of a history of infection or periodontal disease, it is highly recommended that when the tooth is extracted, the socket is then grafted with bone.  This allows the ridge to be preserved, whether for future implant placement, preservation of bone against the adjacent tooth, or  for cosmetic purposes . This procedure is easiest when can be performed in conjunction with the extraction in order to avoid more complicated and costlier procedures in the future when restoring the bone.  There are multiple sources of bone which can be used for this purpose.