Inlays and Onlays: indirect porcelain bonded restorations

A porcelain inlay is similar to a filling, but instead of being built up in your mouth, an inlay is constructed indirectly from a model of your teeth. It is usually made of porcelain, but is sometimes made from metals, usually gold and other metals. Making it outside the mouth, means materials can be used that would not be possible in the mouth. Porcelain is fired at very high temperatures, meaning it cannot be directly made in the mouth. Gold melts at high temperatures and cannot be done in the mouth. Instead bonded white fillings made of composite are made in the mouth directly. These materials can be weaker and due to the restricted area and moisture, the final restoration is not as strong or long lasting. A porcelain inlay is a good alternative to a large bonded filling

A porcelain inlay or a gold inlay is strong and longer lasting for larger restorations. This can then be bonded to the tooth directly in the mouth. After bonding, it functions like a tooth again. The extra time and better working environment mean the inlay should look and function better than a filling, but it is still dependent on the tooth being strong enough to take the load, having no cracks in the remaining walls and having enough remaining enamel for bonding. If this is not the case, a crown with a full covering made of porcelain can be considered. An inlay means a longer treatment time and usually an increased cost.

How much does an inlay cost?

The cost of an inlay varies depending on size and complexity. For a 3 surface inlay, the most common, the cost is approximately $880, but they range from $690 to $1200 depending on surfaces. Discounts may be offered for multiple teeth treated at once as we pass on the savings in time and materials to you. When you come for your examination or consultation, we will give you a quote for exact costs and item numbers to claim from your health fund, if you have one.

What is the process of getting a porcelain inlay?

Due to the extra work involved, a porcelain inlay usually requires two visits. The first visit with the dentist is for preparation of the tooth and for moulds of your teeth to be taken. These are then sent to the dental laboratory for manufacture. Another visit to bond the inlay to your tooth is made for later, after it has been constructed. The extra expense and effort can be worth it, as over the long term, replaced less frequently means less damage to the tooth over time and thus less expense from repeated replacement. During the period between visits, you would normally have a temporary filling on your tooth. This is included in the cost of the inlay.

What is the difference between an inlay and an onlay?

An inlay is inserted into your tooth, between different walls, whereas an onlay covers over the top of your tooth, often when the walls are more damaged. Both are made in the same way, just slightly different shapes. There is crossover in what is considered an inlay and what is an onlay.