Gold onlays and inlays and crowns are the most durable dental restorations that have ever been placed in human teeth. They have out lasted all other restorations by dozens of years, and have the great advantage of being extremely conservative in the amount of tooth structure that needs to be removed to make them.
Gold restorations are completely inert and cannot break. They only fail because they are ground through, or because the teeth get decayed around them. In clinical practice it is not uncommon to find gold restorations in the mouths of eighty and ninety year olds which had been placed fifty year beforehand.
There disadvantage is their color and cost. They are technically demanding to prepare and make well, but there ability to out last all the new materials causes much chagrin to the dental supply companies who market prettier but less durable materials. It is possible for a skilled clinician to engineer a gold onlay or inlay so that it does not show in the smile. We strive to make gold onlays well in our practice.
It is possible that the new Zirconium restorations will give the gold onlay a run for its money, and last as long, but that remains to be seen when 2030 rolls around. However, this new porcelain alternative requires much more aggressive tooth reduction because it needs to be much thicker than gold for stength.
Beautiful gold inlays that will out last all other materials and are designed not to show in the smile. From the Tucker Study Club