You may know inlays and onlays as a partial crown. These take the current natural tooth and fit the inlay or onlay on the tooth. This process is great for strengthening the tooth to prevent future or further damage and to restore its shape. An inlay would be used when there is no damage to the tooth and it can be placed right on the existing tooth. An onlay would be used when damage has occurred to the existing tooth.
The first part of the procedure is removing the decayed area of the tooth then a mold of the tooth is done. By combining porcelain, gold or a composite resin they form the restoration which can take two to three weeks to complete. During that time a temporary inlay or onlay would be used. Your next visit the custom made inlay or onlay would be cemented into your mouth and you'll have a natural look where nobody can see the work done!