Inlays and onlays are restorations which can repair teeth with mild to moderate decay. Teeth that are too damaged to accept a traditional filling can benefit from inlay or onlay treatment. An inlay is similar to a filling, as it covers the inside of the cusps of the teeth. An onlay is a larger restoration, as it extends to cover one or more cusps of the teeth. Inlay and onlay restorations actually strengthen the tooth and are a great option when a tooth restoration doesn’t require an entire crown.