Clinicians face the difficult task of judging the influence and significance of multiple risk factors of periodontal, endodontic, or prosthetic origin that can affect the prognosis of an abutment tooth.

When deciding if a compromised tooth of questionable prognosis should be maintained or replaced by an implant, both local, side-specific and more general patient-related factors should be considered.

While single risks are possibly accepted for single tooth restorations, teeth with questionable prognosis and multiple pretreatment requirements are better not included as abutments in fixed dental prosthesis to reduce the risk to survival of the entire restoration.

The strategic use of dental implants and smaller units (short-space fixed dental prostheses), either tooth- or implant-supported, as well as natural tooth abutments with good prognoses for long-span FDPs, should be strived for to minimize the risk of failure of the entire restoration.