Chairside - Glidewell Dental Labs

Figure 10: A provisional restoration is fabricated from a preoperative
impression taken prior to preparation of the fractured unit. Flowable composite
resin was used to fill in the fracture prior to taking the impression, so
that the provisional restoration would have the correct contours.
Figure 11: The fabricated saddle crown on the master laboratory model,
shown from the facial aspect
The saddle crown consists of a
facial and lingual surface only.
These surfaces are only joined
proximally incisal to the solder
joint of the existing bridge.
Figure 12: Incisal view of the preparation as seen on the master laboratory
model
A provisional restoration is then fabricated using a bisacrylic
provisional material (Luxatemp ® [DMG America])
and is cemented with polycarboxylate cement (Fig. 10).
Digital photographs are provided to the ceramist to aid
in characterization.
Figure 11 is a facial view of the saddle crown on the laboratory
cast model. An incisal view of the master cast shows
the preparation design that basically strips the porcelain
down to the metal substructure on the facial and lingual,
and is “tied in” with a continuous mesial and distal proximal
finish line on the metal connectors of the preexisting
bridge (Fig. 12). A proximal view of the completed restoration
highlights the “saddle” design (Fig. 13). Interproximal
margins are in metal and are located incisal to the metal
connectors of the understructure. The lingual surface of
the restoration is made in metal to match the preexisting
bridge and limit the amount of lingual reduction (Fig. 14).
The completed saddle crown is tried in after removal of
the provisional restoration (Fig. 15). After verification of fit
and checking occlusion with articulating paper, the restoration
is ready for cementation. In this case, resin-modified
glass ionomer cement was used (Fig. 16). A 4-META-type
cement is also good to cement metal to metal if retention
is less than ideal. The cement is mixed according to the
manufacturer’s instructions (Fig. 17) and pushed into place
on the preparation (Fig. 18). It is recommended to hold the
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