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Case selection
Appropriate case selection is important when considering the provision of fixed bridgework. Patient expectations should be discussed and a thorough patient history should be obtained. Replacement of missing teeth with fixed bridgework may not always be indicated and both patient factors alongside restorative factors should be considered before deciding if providing fixed bridgework is appropriate. The survival rate of bridgework can be affected by the span of bridge needed, the proposed position of the bridge, and the size, shape, number and condition of planned abutment teeth. Furthermore, any active disease including caries or periodontal disease should be treated and followed by a period of maintenance to ensure patient compliance in maintaining appropriate oral hygiene.

Abutment evaluation
When a single tooth requires a crown, the prosthetic crown will in most instances rest upon whatever tooth structure was originally supporting the crown of the natural tooth. However, when restoring an edentulous (without teeth) area with a bridge, the bridge is almost always restoring more teeth than there are root structures to support, for instance a 5-tooth bridge supported on three abutment teeth.

To determine whether or not the abutment teeth can support a bridge without failure from lack of support from remaining root structures, the dentist employs Ante's rule&mdash;which states that the roots of abutment teeth must have a combined surface area in three dimensions that is more than that of the missing root structures of the teeth replaced with a bridge. When the situation yields a poor prognosis for proper support, double abutments may be required to properly conform to Ante's rule.

When a posterior tooth intended for an abutment tooth already possesses an intracoronal restoration, it might be better to make that bridge abutment into an inlay or an onlay, instead of a crown. However, this may concentrate the torque of the masticatory forces onto a less enveloping restoration, thus making the bridge more prone to failure.

In some situations, a cantilever bridge may be constructed to restore an edentulous area that only has adequate teeth for abutments either mesially or distally. This must also conform to Ante's rule but, because there are only abutments on one side, a modification to the rule must be applied, and these bridges possess double abutments in the majority of cases, and the occlusal surface area of the pontic is generally decreased by making the pontic smaller than the original tooth.

Indications for use of fixed prostheses in replacement of missing teeth

 * 1) Replacement of a single tooth or a small spanning space.
 * 2) Good oral health status and motivation of patient to maintain oral health.
 * 3) Periodontal status of remaining dentition at a stable and satisfactory level.
 * 4) Abutment teeth of good quality with minimal restorations and enough surface area and enamel present for adhesion.
 * 5) Splinting of periodontally compromised teeth to improve occlusal stability, comfort and decrease mobility. (Periodontally compromised teeth is also a contraindication).
 * 6) As a way of fixed retention after orthodontic treatment or extraction.
 * 7) Patient unsuitable for implants. This may be due to inadequate bone levels, expense or patient not wanting to receive implants.

Contraindications for use of fixed prostheses in replacement of missing teeth

 * 1) Size of saddle area too long.
 * 2) Patients with parafunction e.g. bruxism.
 * 3) Tooth mobility increases risk of de-bonding.
 * 4) Malaligned teeth resulting in poor aesthetics and  common path of insertion.
 * 5) Abutment tooth quality inadequate for example may have a reduced surface area, reduced enamel or be heavily restored.
 * 6) Increased risk of caries due to increased difficulty in maintaining oral hygiene around the bridgework.
 * 7) Increased risk of loss of vitality.
 * 8) Allergy to base metal alloys e.g. nickel