A dental cavity is structural damage to a tooth caused by decay. Decay begins when bacteria consume sugars and starches, producing acids that erode the hard outer layer of the tooth, the enamel. A dental filling is the standard restorative treatment, designed to repair this damage and restore the tooth’s form and function. The goal is to eliminate the infection and prevent further destruction of the tooth structure.
How Fillings Halt Tooth Decay
The core function of a dental filling is to physically interrupt the progression of decay within the tooth. Before placement, the dentist carefully removes all decayed and infected material from the tooth structure. This removal is necessary because any remaining bacteria would allow the decay process to continue underneath the restoration.
Once the decay is removed, the space is thoroughly cleaned and disinfected. The filling then seals off this area, creating a protective barrier against the oral environment. This seal prevents new bacteria and moisture from re-entering the tooth, effectively stopping further acid attacks.
The filling also prevents the infection from advancing deeper toward the tooth’s pulp, which contains the nerves and blood vessels. The hardened material restores the tooth’s structural integrity, allowing it to withstand the forces of biting and chewing. This action ensures the tooth returns to normal function without risking fracture.
Types of Filling Materials
The choice of filling material is determined by the size and location of the cavity, cost, and aesthetic preferences.
Composite Resin
Composite resin is one of the most common materials used today, consisting of a blend of plastic and fine glass particles. Its main advantage is its ability to be color-matched precisely to the natural tooth, making it a highly aesthetic option for visible teeth. Composite fillings bond directly to the tooth structure but have a shorter lifespan, lasting approximately 5 to 10 years.
Amalgam
Amalgam, often called “silver fillings,” is a durable and cost-effective option made from a mixture of metals, including silver, tin, copper, and mercury. It is known for its strength and longevity, lasting 10 to 15 years or more, making it suitable for molars that endure heavy chewing pressure. Amalgam’s metallic color is noticeable, and it does not bond directly to the tooth.
Gold
Gold fillings are custom-made alloys that offer superior durability and resistance to corrosion, lasting 15 to 20 years or longer. Gold is biocompatible and wears down similarly to natural tooth enamel. However, it is the most expensive material and requires at least two appointments for placement.
Glass Ionomer Cement
Glass ionomer cement is composed of acrylic and a glass powder that slowly releases fluoride. This fluoride release helps prevent secondary decay around the filling. It is generally weaker than other options and is used for small cavities, temporary restorations, or in areas with lower biting stress.
What Happens During the Filling Procedure
The process of receiving a dental filling begins with the dentist administering a local anesthetic to numb the area around the affected tooth. Once numb, the dentist uses a high-speed dental drill or other instruments to carefully remove the decayed tissue.
After the decay is eliminated, the cavity is thoroughly cleaned. For composite resin fillings, a special adhesive is applied to the prepared surface to establish a strong bond. The filling material is then placed into the cavity in small increments, with each layer hardened, or “cured,” using a focused blue light.
The dentist then shapes and sculpts the material to match the tooth’s natural contours and biting surface. Finally, the filling is polished, and the dentist checks the patient’s bite to ensure the restoration aligns comfortably with the opposing teeth. Minor adjustments are made if necessary to prevent uneven pressure points when chewing.
Maintaining Your Dental Filling
To maximize the longevity of a dental filling, good oral hygiene is essential. Brushing twice daily with fluoride toothpaste and flossing once a day helps prevent plaque buildup and new decay around the filling edges. Regular dental checkups and cleanings allow the dentist to monitor the filling’s condition and spot early signs of wear or damage.
Patients should avoid chewing hard items, such as ice or hard candies, which can fracture the filling material or the surrounding tooth. Individuals who grind or clench their teeth (bruxism) may benefit from wearing a custom nightguard to protect the restoration from premature wear. Sensitivity to hot or cold temperatures after the procedure is common but should subside; persistent pain or a noticeable chip requires professional evaluation.