When a filling stops being enough

A cavity can be repaired with a filling. Composite fillings are tooth-coloured, while amalgam fillings are silver-coloured.

Inlays and onlays preserve partial coverage rather than covering the whole tooth. Gold, metal ceramic, all-ceramic, and zirconia materials can be used for partial as well as full-coverage restorations.

The distinction is the amount of coverage: fillings repair cavities, inlays and onlays are partial coverage, and complete coverage restorations are used especially where tooth structure loss is more than 50%.

A systematic review reported a mean survival rate of 90.89% for inlays. It also found that the available studies were too heterogeneous for a meaningful comparison between restoration types or materials.

Repeated acid exposure can weaken enamel until it breaks down into a cavity. Untreated tooth decay can cause pain, infection, and tooth loss.

Complete coverage restorations are used extensively, especially when loss of tooth structure is more than 50%. Crowns can be made from gold, metal ceramic, all ceramic, or zirconia.

The central question is coverage. A filling repairs the cavity, an inlay or onlay restores part of the tooth, and a crown gives complete coverage when tooth structure loss is extensive.