Bridges can either be provisional (temporary / interim) or permanent. The provisional bridge is a transitional restoration that protects the teeth that are weakened by the preparation, and stabilizes the dental tissues till the fabrication of the final restoration, moreover, it can pave the way to the esthetics of the future permanent restoration and its appearance, which can help the patient accept the final profile. Provisional restorations are designed to be used for a few weeks to months, they can be fabricated directly (by chair side), or indirectly ( in the dental laboratory). It is usually tried in a few times to check if it fits properly and if its margins are well adapting on the teeth surface and gingiva, it may need relining or a few adjustments. Provisional bridges can either be made of acrylic resins or metal.
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