A dental filling is a routine procedure used to repair a tooth damaged by decay, or a cavity. This damage occurs when oral bacteria produce acids that erode the tooth’s outer layer of enamel. The primary function of a filling is to seal this compromised area, halting the progression of decay and restoring the tooth’s original form and chewing capability.
Preparing the Tooth for Restoration
The filling process begins with the administration of a local anesthetic, typically an injection near the affected tooth, to ensure the patient remains comfortable throughout the procedure. Once the area is numb, the dentist uses specialized tools, often a high-speed dental handpiece or a laser, to remove all carious tissue. This step is meticulous, as any decayed material left behind could allow the cavity to continue growing beneath the future restoration.
After the decay is excavated, the remaining tooth structure is cleaned and shaped to create a preparation site that can securely hold the filling material. Dentists may use a rubber dam or cotton rolls to isolate the tooth, keeping the area dry and free from saliva contamination, which is important for moisture-sensitive materials like composite resin. The final preparation is ready to receive the restorative material.
Placing and Shaping the Filling Material
With the cavity clean and prepared, the dentist begins placing the filling material. For composite resin fillings, a specialized acid-etching gel is applied to the enamel and dentin surfaces to microscopically roughen the tooth. This etching process creates tiny pores that allow for a strong mechanical bond with the subsequent adhesive layer.
A liquid bonding agent is then painted onto the conditioned tooth surface and cured with a specialized blue light, forming a hybrid layer that chemically links the tooth to the filling material. The composite resin is placed into the cavity preparation in small, incremental layers. Each layer is individually hardened using the curing light, which activates photoinitiators within the resin to solidify the material.
Once the cavity is filled, the dentist contours and shapes the material to mimic the tooth’s natural anatomy, including the cusps and grooves. The patient’s bite is checked using a thin articulating paper that marks any high spots on the new filling. Final adjustments are made by grinding away excess material, followed by polishing to create a smooth surface that resists plaque accumulation and does not interfere with the natural bite.
Types of Dental Filling Materials
The choice of restorative material significantly influences the procedure and the long-term performance of the filling. Composite resin fillings are favored for their aesthetic qualities, as they are a mixture of acrylic resin and finely ground glass particles that can be shade-matched to the natural color of the tooth. These fillings bond directly to the tooth structure, which helps support the remaining tooth material and prevent fracture. However, composite fillings may be less durable than amalgam in areas of heavy biting force and are more expensive due to the complex, moisture-sensitive placement technique.
Dental amalgam, frequently referred to as silver fillings, is a robust mixture of metals, including silver, copper, tin, and liquid mercury. This material is prized for its exceptional strength and longevity, making it a reliable choice for large cavities in the back chewing teeth. Amalgam is also more cost-effective and less sensitive to moisture during placement compared to composite. The primary drawback is its metallic appearance, and its placement requires more removal of healthy tooth structure to create a shape that mechanically holds the filling in place.
Life After the Procedure
Immediately following the procedure, the patient will experience residual numbness from the local anesthetic, which typically lasts for one to three hours. Patients should avoid chewing on the treated side until sensation fully returns to prevent accidentally biting the cheek, lip, or tongue. Once the numbness subsides, temporary sensitivity to hot, cold, or sweet stimuli is common as the tooth’s nerve adjusts to the new restoration.
This mild sensitivity usually fades within a few days to a couple of weeks as the tooth recovers. Patients should be cautious with their diet immediately after treatment, avoiding hard or sticky foods that could damage a newly placed filling. While composite fillings are hardened instantly by the curing light, amalgam fillings require up to 24 hours to reach their final strength. If the filling feels high when biting down after the numbness wears off, a follow-up appointment is necessary for adjustment to prevent discomfort and possible damage.