Understanding and using biomechanical theories that effect endosseous implant design may improve the performance of implants in varying load conditions and allow the clinician to better apply this information with potentially improved success rates. The following article presents information from English peer-reviewed journals identified by a Medline search covering the years from 1974 through 2004, and attempts to integrate information available in the dental literature and address current controversies and issues in selecting diameter, length, and shapes of dental implants.