The purpose of this article is to identify the incidence of complications and the most common complications associated with single crowns, fixed partial dentures, all-ceramic crowns, resin-bonded prostheses, and posts and cores. A Medline and an extensive hand search were performed on English-language publications covering the last 50 years. The searches focused on publications that contained clinical data regarding success/failure/complications. Within each type of prosthesis, raw data were combined from multiple studies and mean values calculated to determine what trends were noted in the studies. The lowest incidence of clinical complications was associated with all-ceramic crowns (8%). Posts and cores (10%) and conventional single crowns (11%) had comparable clinical complications incidences. Resin-bonded prostheses (26%) and conventional fixed partial dentures (27%) were found to have comparable clinical complications incidences. The 3 most common complications encountered with all-ceramic crowns were crown fracture (7%), loss of retention (2%), and need for endodontic treatment (1%). The 3 most common complications associated with posts and cores were post loosening (5%), root fracture (3%), and caries (2%). With single crowns, the 3 most common complications were need for endodontic treatment (3%), porcelain veneer fracture (3%), and loss of retention (2%). When fixed partial denture studies were reviewed, the 3 most commonly reported complications were caries (18% of abutments), need for endodontic treatment (11% of abutments), and loss of retention (7% of prostheses). The 3 most common complications associated with resin-bonded prostheses were prosthesis debonding (21%), tooth discoloration (18%), and caries (7%). (J Prosthet Dent 2003;90:31-41.) A complication has been defined 1 as "a secondary disease or condition developing in the course of a primary disease or condition." Although complications may be an indication that clinical failure has occurred, this is not typically the case. It is also possible that complications may reflect substandard care. But once again, this is usually not true. Most of the time, complications are conditions that occur during or after appropriately performed fixed prosthodontic treatment procedures.Knowledge regarding the clinical complications that can occur in fixed prosthodontics enhances the clinician's ability to complete a thorough diagnosis, develop the most appropriate treatment plan, communicate realistic expectations to patients, and plan the time intervals needed for post-treatment care. Although a plethora of articles present clinical complications data, none provide a comprehensive comparison of the complications associated with the most commonly used restorations/ prostheses.One of the purposes of this article is to present data regarding the incidence of clinical complications associated with the following restorations/prostheses: single crowns (all-metal, metal ceramic, resin veneered metal); fixed partial dentures (all-metal, metal ceramic, resinvenee...