Filling, inlay/onlay, or crown
A crown covers a badly weakened tooth, while an inlay or onlay preserves more of the tooth around a repair.
[2]The short answer
A filling repairs a small area, an inlay or onlay replaces part of a tooth, and a crown covers it completely when more structure is lost.
[2]
The two options, side by side

Which option fits the tooth?
Choose a filling, inlay, or onlay if
Choose a crown if
How do the costs differ?
How long can they last?
Published survival figures depend on the study and follow-up period. One comparison reported 95.30% for inlays, 97.00% for onlays, and 96.10% for crowns; at five years another reported 98.90% for inlays and onlays and 97.40% for crowns.
[2]What can go wrong?
Partial and complete restorations can fracture or chip, lose retention, develop recurrent decay, or have endodontic complications. In all-ceramic restorations, severe staining at the margin can occur; crown reports also included core failure.
[2]When might none of these be enough?
What guides the choice?
Frequently asked questions
Does an onlay cover more tooth than an inlay?
Yes. Both are partial restorations, but an onlay extends over more of the tooth than an inlay.
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