Porcelain fillings are created from a high-grade dental ceramic and used to restore and protect a tooth that has a cavity or minor damage. Each filling is produced in a dental laboratory to exactly fit the damaged tooth. True porcelain fillings should not be confused with white composite fillings that contain glass or porcelain in a matrix of plastic resin and may be erroneously referred to as porcelain fillings. Advantages of porcelain fillings include durability, a natural look and the lack of mercury or other metals. The main disadvantage is that at least two dental appointments are required, creating greater expense and time.
There are two types of porcelain fillings, inlays and onlays. An inlay is positioned within the cavity in the tooth, as other types of fillings are. Onlays can cover part of the cusp of the tooth in addition to the cavity. Both inlays and onlays are an indirect method of filling a decayed or damaged tooth, as the filling is produced in a dental lab rather than created within the tooth while at the dentist’s office. By using computer imaging or taking an impression of the tooth, the dentist will ensure the porcelain filling exactly fits the tooth.
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Dental cement is used to bond porcelain fillings to the tooth. As the porcelain material is brittle, the patient should choose a dentist experienced in this type of filling to lessen the risk of cracking it during positioning. Compared to metal fillings, porcelain ones have been shown to strengthen the tooth. Porcelain does not expand and contract with temperature changes as metal fillings do, possibly damaging the tooth.
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Widely used in cosmetic dentistry, porcelain fillings cannot be detected by the eye. Their slight translucence, color and texture closely resemble natural tooth enamel. During the initial office visit, the color of the tooth is determined, and the porcelain filling is made to perfectly match the patient’s natural color. Porcelain is stain resistant and does not discolor over time. The durability of porcelain is similar or superior to natural tooth enamel, and the fillings last for many years.
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Two disadvantages of porcelain fillings are their cost and the time required to produce a filling. At least two office visits are necessary. First, the initial work preparing and measuring the tooth is required. Then, another visit is needed for the insertion and bonding of the filling. Patients need to wait longer than with metal fillings, as each porcelain filling must be custom made in a dental lab.