Many of you probably know the routine. It starts out with a cavity in a tooth or several teeth. This cavity is filled by the dentist when the decay is noticed. The filling material was probably silver amalgam. Some years pass by, and a part of the filling or even a part of the tooth may break off. When an emergency visit is made to the dentist you are informed that the tooth needs a “crown” due to the fact that the tooth is weak and there is too much tooth structure missing to replace it with another filling. So the tooth is prepared for the crown by removing much healthy tooth in order to place a crown on it. Well, advances in “adhesion” dentistry have almost made this a thing of the past. Esthetic inlays and onlays replace damaged tooth while being very strong and blending almost imperceptibly with the natural tooth. They are also very conservative.
What is an esthetic inlay or onlay? They can be made out of a strong porcelain or resin plastic material, depending on the application. They usually look like a piece of a 3D jigsaw puzzle, replacing only the part of the tooth that is damaged. The dentist will remove only the damaged part of the tooth and any decay present. The tooth is then prepared slightly to remove any rough edges or undercuts. An impression is taken just like for a traditional crown, and a temporary is placed. Two to three weeks later, the temporary is removed and the inlay or onlay is bonded to place.
It is this bonding process that contributes to the strength of the finished product. A special bonding resin is used to micromechanically bond the inlay or onlay, much like multipurpose or wood glue is used to bond things together. The bonded tooth is strong enough to withstand the forces of chewing and to last a long time. The bonding process restores the tooth to 90-95% of original strength, all the while being very conservative.
While a full crown on a tooth can be very strong, even stronger than the original tooth, they can be very difficult to keep clean, leading to possible decay under the margins. A full crown can also be very uncomfortable to chew on, feeling unnatural. While there still are a few applications for full crowns, most teeth needing something stronger than a filling can be restored with an inlay or onlay. They are conservative, easier to keep clean, comfortable and natural, and very strong. The new age of dentistry is here. Ask your dentist today!
