Dental restorations, commonly known as fillings, are frequent procedures used to repair damage and preserve tooth structure. While many fillings address decay on chewing surfaces, the Class V restoration focuses on a unique and vulnerable area near the gum line. Understanding this specific restoration involves knowing where it is located, what causes the damage, and the precise process used to repair it.
Defining the Class V Restoration
A Class V restoration is defined by its specific location on the tooth, which is standardized within the dental profession. Dentists utilize the G.V. Black classification system to categorize lesions based on their position, providing a universal language for diagnosis and treatment planning. This systematic approach groups all cavities occurring on the smooth surfaces of teeth near the gum line into the Class V designation. These lesions are found on the gingival or cervical third of the tooth. They can appear on any tooth in the mouth, affecting either the facial surface—the side facing the cheek or lip—or the lingual surface.
Primary Causes of Class V Lesions
The reasons Class V lesions develop are often different from the causes of typical cavities found on chewing surfaces. While traditional dental caries, or decay, can occur here due to plaque and bacteria accumulation at the gum line, many Class V lesions are considered non-carious. This means they are not caused by acid-producing bacteria, but rather by mechanical or chemical wear.
Abrasion and Erosion
One common cause is abrasion, which involves the physical wearing away of tooth structure by an external force, most frequently aggressive or incorrect horizontal toothbrushing. This mechanical wear often results in a notched appearance at the tooth’s neck, particularly when combined with abrasive toothpastes. Another primary cause is erosion, the chemical dissolution of the tooth surface from exposure to acids. These acids can come from the diet, such as frequent consumption of high-acidity foods and drinks, or from gastric sources like acid reflux.
Abfraction
Non-carious cervical lesions are also sometimes attributed to abfraction. Abfraction suggests that excessive biting forces, such as clenching or grinding, create stress that causes small pieces of enamel to flake away at the weakest point near the gum line. Often, a Class V lesion is a mix of these factors, where acid exposure softens the enamel, making it more susceptible to wear from toothbrush abrasion.
Materials and Restoration Process
The clinical procedure for a Class V restoration involves carefully preparing the damaged area and then selecting a material suited to the lesion’s specific characteristics and location. If the lesion is deep or close to the nerve, a local anesthetic may be administered to ensure patient comfort. The dentist then removes any compromised tooth structure, creating a clean surface ready for the restorative material.
Material Selection
Material selection is determined by factors like the need for aesthetics, the patient’s risk for new decay, and the challenge of keeping the area dry during the procedure. Composite resin, a tooth-colored plastic mixture, is frequently used for its excellent aesthetic blending and durability in areas where moisture can be controlled. Glass ionomer cement (GIC) or resin-modified glass ionomer cement (RMGIC) are also common because they can release fluoride, which helps prevent future decay, and they tolerate some moisture during placement, making them suitable for areas difficult to isolate near the gums.
Placement
Once the preparation is complete, a bonding agent is applied to help the restorative material adhere securely. The material is then placed into the prepared area, carefully shaped to match the natural contour of the tooth, and hardened—often with a specialized blue light. The final steps involve adjusting the filling so it feels smooth and comfortable, followed by meticulous polishing to create a seamless transition with the natural tooth structure.
Post-Treatment Care and Longevity
Following the placement of a Class V restoration, patients may experience temporary sensitivity, particularly to cold temperatures, because the filling is placed close to the gum line. This sensitivity typically subsides within a few weeks as the nerve tissue adjusts to the new filling. Patients should continue their routine oral hygiene but with necessary adjustments to protect the restored area.
To maintain the filling, it is recommended to use a soft-bristled toothbrush and a non-abrasive toothpaste, employing a gentle, rolling motion rather than aggressive scrubbing. The longevity of a Class V restoration is highly variable, often ranging from five to fifteen years, and depends on the material used and the size of the original defect. The most significant factor affecting its lifespan is whether the underlying cause of the lesion is addressed. If the original cause was aggressive brushing, a corrected technique is necessary to prevent abrasion along the margin of the new filling. If the cause was acid erosion, dietary changes or management of acid reflux are paramount to prevent the material from dissolving or the lesion from reforming. Long-term success is achieved through a combination of professional placement and the patient’s commitment to eliminating the damaging habits.