Fixed-Fixed Partial Denture
Fixed-fixed Partial Denture, also known as fixed-fixed dental bridge, is a design of fixed partial prosthesis that has a rigid connector at both ends of the pontic. This basic design of FPD has a minimum of three units that can be cemented in one piece. The abutment teeth are rigidly splinted together and must be prepared parallel to each other. Its retainers or crowns should have approximately the same retention as each other. This is to minimized the risk that forces applied to the fixed-fixed FPD will dislodge one retainer from its abutment, leaving the FPD suspended from the other abutment.
Its retainers (crowns) should cover the entire occluding surface of all the abutment teeth. Otherwise an occlusal force directed at the unprotected area will depress the abutment tooth in its socket while the retainer is held by the FPD and the other abutment. This will break down the cement causing leakage. Leakage will result to secondary caries.
The advantages of Fixed-fixed Partial Denture are:
Fixed fixed FPD is a robust design with maximum retention and strength.
Abutment teeth are splinted together which may be an advantage for teeth that are mobile.
This design of fixed prosthesis is the most practical for larger FPDs particularly when there has been periodontal disease.
The construction of the fixed-fixed bridge FPD in the dental laboratory is simple.
Fixed-fixed partial denture design has the following disadvantages:
Fixed-fixed FPD requires preparation to be parallel. This results to more tooth reduction which may endanger the pulp. The strength of the abutment may also be reduced.
The tooth preparation is sometimes slow because the parallelism should always be checked.
All the retainers / crowns are major retainers, which require extensive tooth preparations.