- Any amount of decay on a portion of any tooth
- Need for a long-term, durable restoration
- Desire to limit the amount of healthy tooth structure removed
- Need to strengthen and reinforce tooth
Decay is removed and cleaned from the tooth and a highly accurate impression or mold is made of the prepared surface. This mold is used to create a model of the tooth which is then sent to a special laboratory that will create a gold, porcelain or ceramic restoration called an inlay or onlay. The inlay or onlay is then cemented into the prepared surface of the tooth. An inlay covers only one or two surfaces of the tooth and is used to restore a small amount of decay. An onlay actually covers one or more cusps.
Inlays and onlays are incredibly strong due to the fact that they are created in a laboratory. This protects the tooth from fracturing and actually strengthens the tooth. In addition, inlays and onlays fit almost perfectly into the prepared surface of the tooth, reducing the size of the seam between the restoration and the tooth. This helps keep decay from eventually occurring under the restoration. Inlays and onlays require the removal of only decayed areas of the tooth, leaving more healthy tooth structure intact. This can help prevent the expense of root canal therapy in the future.
Due to the fact that they are crafted in a laboratory, inlays and onlays require a greater initial investment than regular fillings. However, in the long run, inlays and onlays are a better investment than fillings due to their extremely long life and highly accurate fit. Gold inlays and onlays generally have a greater long term durability than porcelain or ceramic inlays and onlays.
In cases of extensive decay, crowns are the best alternative.