A dental filling is a restorative dental material placed into a prepared cavity to repair a tooth damaged by caries (decay), fracture, or abrasive wear, restoring its anatomical form, function, and structural integrity. When decay erodes the enamel and penetrates the underlying dentin, a filling halts further bacterial progression and seals the tooth against reinfection.
Types of Dental Fillings
Material selection depends on the size and location of the lesion, esthetic requirements, occlusal load, and patient preference. Common options include:
- Composite resin — a tooth-colored polymer that bonds directly to tooth structure; the preferred choice for visible anterior and posterior teeth.
- Dental amalgam — a durable silver-colored alloy of mercury, silver, tin, and copper; historically the standard for high-load posterior restorations.
- Glass ionomer cement — chemically bonds to dentin and releases fluoride; used in lower-stress areas and pediatric dentistry.
- Gold or ceramic inlays and onlays — indirect restorations fabricated in a lab and cemented in place; offer exceptional longevity for larger cavities.
How the Procedure Works
After local anesthesia is administered, the clinician removes all carious dentin with a dental handpiece or hand instruments. The cavity is shaped for retention and resistance form, then conditioned and bonded before the restorative material is placed and contoured to replicate natural tooth morphology. For composite restorations, a curing light polymerizes the resin in incremental layers. Occlusion is then verified and refined so the restoration integrates seamlessly with the patient’s bite.
Why It Matters
A carious lesion left untreated can progress through the dentin and reach the dental pulp, escalating treatment needs to root canal therapy or extraction. Timely placement of a filling is among the most cost-effective interventions in dentistry — it preserves natural tooth structure, maintains arch integrity, and prevents far more invasive procedures down the line. Well-adapted restoration margins also reduce the risk of secondary (recurrent) caries developing at the margin interface.
Routine radiographic monitoring and clinical examination are essential for catching marginal breakdown or recurrent decay early, ensuring every restoration delivers the longest possible service life.