Which statement describes an Onlay?

Which statement describes an Onlay?

• A. It replaces one or more cusps
• B. It does not involve the cusps
• C. It seals grooves
• D. It covers the entire tooth

Answer: (A)

Onlays are indirect restorations that extend over one or more cusps of a tooth, not the entire tooth. That partial-coverage nature is what the statement captures, making it the best description. An onlay protects and restores the chewing surfaces by spanning cusps, while preserving other tooth structure. If a restoration doesn’t involve cusps, that would be an inlay; if the entire tooth were covered, that would be a crown; sealing grooves refers to a preventive sealant rather than a restorative coverage.

Onlays are indirect restorations that extend over one or more cusps of a tooth, not the entire tooth. That partial-coverage nature is what the statement captures, making it the best description. An onlay protects and restores the chewing surfaces by spanning cusps, while preserving other tooth structure. If a restoration doesn’t involve cusps, that would be an inlay; if the entire tooth were covered, that would be a crown; sealing grooves refers to a preventive sealant rather than a restorative coverage.