Fixed oral prosthesis as of late has been a very viable option for oral rehabilitation, since these differ from removable prostheses in aesthetic, functional and biological parameters. As a result, they are always preferred by patients. Oral prosthesis´ have certain parameters to be fulfilled for its prosthetic indications, such as the number of teeth present in the mouth, the type of occlusion, the level of bone insertion in dental organs that will be used as pillars or stumps, the proportion of root to crown , the absence of periradicular lesions that put us in reserved forecasts for the rehabilitation of dental organs. Under the ideal parameters we will base the final diagnosis for the placement of the correct restoration either in the same prosthetic design, manufactured with an ideal material. The preservation of the residual edge in the edentula area will be respected so that the prosthesis does not play an irritating role within the oral cavity, a relevant factor when placing this type of restorations. A bad adjustment either in individual crowns, fixed bridges can chronically irritate the residual flange resulting in ulcerative, fungal or bacterial lesions. Biological thicknesses, residual flanges must always be respected when designing this type of definitive restorations.