In days long since past, silver or gold fillings were the only options available for filling cavities. Over the past four decades, new fillings have been developed which blend in with the color of the teeth, making them almost undetectable. Due to limitations in the materials used, these fillings were normally reserved for cavities in the front teeth, but now, with the many scientific advances made, cosmetic fillings can be done anywhere in the mouth.

There are two basic types of cosmetic, or tooth-colored filling materials which are widely used in Dentistry today: Composite and Porcelain.

Composite Fillings
Composite is a resin-based tooth filling material. It is used almost exclusively to fill cavities in the front teeth, and in recent years used also to fill cavities in the back teeth. The most common type of composite comes in the form of thick putty which is directly condensed into the cavity after all decay has been cleaned out. It is chemically bonded to the tooth, which is why these types of fillings are often referred to as “bonded restorations.” The primary disadvantage to these directly applied composites is relative lack of strength. For this reason very large fillings of this type typically will not hold up well over time.

Porcelain Fillings
Porcelain fillings are usually referred to as “inlays” because they are custom-made in a laboratory to precisely fit the hole in the tooth. (Similarly, inlays can also be made of high-strength composite which is heat and pressure-cured in a laboratory) Inlays are used when the size of the filling dictates the use of a stronger material than directly-applied composite. The inlay, whether it is composed of porcelain or composite, is bonded in place using low viscosity composite resin cement.

Since these restorations are fabricated in a dental laboratory, a temporary inlay is made to fill the cavity for the period of about two weeks while the permanent inlay is being made.

PORCELAIN INLAY PROCEDURE
There are two steps involved: First, all decay is removed from the tooth, and the inside cavity walls are shaped to allow insertion of an inlay. A highly accurate impression is then taken of the tooth from which a plaster model (which is an exact duplicate of the prepared tooth) is made. This plaster model serves as a template for the fabrication in the laboratory of a precisely-fitting porcelain inlay.

Secondly, once the inlay has been made, the temporary inlay is gently removed from the cavity, and the permanent inlay is bonded into the tooth.

Limitations of Porcelain Inlays:
Porcelain inlays are considered to be an intermediate tooth restoration. That is to say, if the cavity is small, then a conventional filling should be adequate. However, if the cavity is very large, or if there has been significant loss of tooth structure, an inlay would be insufficient to restore the tooth. In such a case, a crown, which covers and protects the entire tooth would be indicated.