Completed provisional.
Space Maintenance
Proximal contacts (Figure 2) – A provisional crown or bridge should exhibit good contact with adjacent tooth structure to prevent tooth migration, maintain interproximal tissue health and keep the proper space maintenance for a laboratory fabricated crown or bridge. If the space is not maintained, the final restoration may not fit due to movement of the adjacent teeth.

Figure 2. Proximal contacts.

Figure 3. Occlusal contacts.
Occlusal contacts (Figure 3)– A provisional restoration must maintain good occlusion and occlusal contact with the opposing dentition to keep the opposing teeth from supra-erupting. If the opposing teeth supra-erupt, the final restoration will not fit correctly (the occlusion of the crown will be too high).
Smooth polish
Provisional restorations need a smooth surface finish to promote good gingival health and resist plaque buildup.
Proper Emergence Profile
The natural emergence profile of a tooth deflects food away from the gingival tissue (Figure 4) so that soft tissues are not harmed by mastication (i.e. chewing). A provisional restoration must also provide an appropriate emergence profile.

Figure 4 . Proper emergence profile.

Figure 5. Poor marginal contour.
Adequate Marginal Seal
A sound margin between natural tooth structure and a provisional restoration is important because it eliminates microleakage, helps to minimize plaque retention and promotes gingival healing. Provisional restorations that are over-contoured (Figure 5, arrow A.), or overhang the finish line of the preparation (Figure 5, arrow B.) may result in plaque buildup and, consequently, gingival recession.

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