Frequently Asked Questions 

1. What materials are in an Inlay/Onlay? 

Inlays are made of two types of materials: 

     1. Porcelain - most like a natural tooth in color

     2. Gold Alloy - strongest and most conservative in its preparation

2. What are the benefits of having an Inlay/Onlay? 

Inlays and Onlays restore a tooth to its natural size, shape and–if using porcelain– color. They improve the strength, function and appearance of a broken down tooth that may otherwise be lost.

3. What are the risks of having an Inlay/Onlay? 

In having an inlay/onlay, some inherent risks exist both to the tooth and to the restoration itself. The risks to the tooth are:

• Preparation for an inlay/onlay weakens tooth structure and permanently alters the tooth underneath the restoration.
• Preparing for and placing an inlay/onlay can irritate the tooth and cause “postoperative” sensitivity which may last for up to 3 months.
• The tooth underneath the inlay/onlay may need root canal treatment about 5% of the time during the lifetime of the tooth.
• If the cement seal at the edge of the inlay/onlay is lost, decay may form at the juncture of the restoration and tooth.

The risks to the inlay/onlay are:

• Porcelain may chip and metal may wear over time.
• If the tooth needs a root canal treatment after the inlay/onlay is permanently cemented, the procedure may fracture the restoration and the inlay/onlay may need to be replaced

4. What are the alternatives to Inlays/Onlays? 

• Alternatives to placing an inlay/onlay are to either place a crown or a direct restoration such as tooth colored or silver fillings.
• Crowns are less conservative in their preparation and therefore weaken remaining tooth structure more than inlays/onlays.
• Composite and amalgam restorations remove decay and may restore teeth to their original form but are limited because they:
• - Do not improve the strength of broken down teeth.
• - Do not improve the long term function and aesthetics of broken down teeth as well as inlays/onlays. 

5. How can an existing bite affect an Inlay/Onlay? 

Excessive bite forces may lead to the restoration chipping or breaking. 

6. Are there any post-treatment limitations once I have an Inlay/Onlay? 

• Porcelain on an inlay/onlay may have a good color match with adjacent natural teeth when the restoration is placed but less of a match as your natural teeth age.
• An inlay/onlay may chip or break if used for abnormal activities (e.g., biting fishing line, sewing thread or finger nails, opening bottles).