Dentists use inlays and onlays to save your tooth when a cavity is too large for a filling but not large enough for a crown. Inlays and onlays are prefabricated inserts that fill the cavity caused by a bacterial infection.
Inlays are smaller than onlays and fill a gap between the cusps of a tooth. If the cusps have been damaged due to infection, your dentist uses an onlay that covers the cusps of the tooth as well.
Dental laboratories fabricate inlays and onlays based on measurements made by your dentist. Since they are custom-made, the partial crowns sit comfortably over your tooth.
You brush and floss an inlay or onlay just like you do any other tooth.
A partial crown can last up to 20 years or more as long as you practise good oral hygiene.