Cantilever fixed partial dentures are defined as having one or more abutments at one end of the prosthesis while the other end is unsupported. Much controversy without documentary evidence has surrounded this prosthesis. Despite negative arguments, the cantilever prosthesis has been used extensively by the clinicians. If used nonjudiciously without following proper guidelines these might lead to some complications. 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. Apart from the substandard care, the unique arrangement of the abutments and pontic also accounts for the prime disadvantage: the creation of a class I lever system. When the cantilevered pontic is placed under occlusal function, forces are placed on the abutments. There are various criteria and factors necessary for a successful cantilever fixed partial denture (FPD). The purpose of this paper is to discuss briefly various factors involved in the planning of a cantilever fixed partial denture. 1. Introduction Because of the requests for fixed partial prostheses by patients and because of the extensive restorative procedures used in complete oral rehabilitation, many dentists have been using these partial dentures with free-end pontics. Dentists have used this type of restoration for several years with more than moderate success. However, during this period, the number of failures observed has been too high to be considered the result of accident. Too many roots and crowns fractured of the abutment teeth adjoining the free-end pontic. Also, some of the gold crowns that covered these terminal abutment teeth loosened without the crowns covering the remaining portion of the splint loosening. This was not always detected until caries had caused acute dental pain which involved the pulp and destroyed the crown of the tooth next to the cantilevered pontic. Therefore, it became necessary to probe deeper into the problem [1]. Every dentist realizes that important correlations exist between biology and mechanics in treating patients with either fixed or removable partial dentures. A distribution of stress within physiologic limitations of supporting structures in both types of restorations has been a vital consideration of dentists for many years. It is not uncommon to be confronted with oral situations in which treatment with either a distal extension removable partial denture or a posterior, cantilever type of fixed partial denture is considered. The cantilever fixed
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