Tooth decay is one of the most common dental problems. It can begin as a small area of enamel damage and gradually progress deeper into the tooth if left untreated.

The good news is that many cavities can be treated with a dental filling. When detected early, a filling can restore the tooth without requiring more extensive treatment.

What is a dental filling?

A dental filling is a restorative material used to repair a tooth damaged by decay or minor structural defects. The dentist removes the affected tooth structure when necessary, prepares the area and restores it with a suitable filling material.

The purpose is to restore the tooth's shape and function, protect the remaining structure and help prevent further damage in the treated area.

When do you need a dental filling?

Your dentist may recommend a filling when tooth decay or a small defect has damaged the tooth but enough healthy structure remains for a direct restoration.

Common reasons include:

• Dental cavities caused by tooth decay.
• Small chips or fractures in a tooth.
• Minor defects in existing restorations.
• Some worn areas or non-carious cervical lesions.
• Replacement of a defective or failing filling.

Not every cavity causes pain. Early decay may have no symptoms at all. This is one reason regular dental examinations are important.

What are the different types of dental fillings?

Different materials are available for restoring teeth. The choice depends on the size and location of the cavity, biting forces, moisture control, aesthetic requirements, cost and the patient's individual needs.

1. Composite resin fillings

Composite fillings are tooth-coloured restorations made from a resin-based material containing inorganic filler particles. They can be closely matched to the natural shade of the tooth.

• Natural-looking tooth-coloured appearance.
• Can bond to tooth structure with an appropriate bonding protocol.
• Useful for many front and back tooth restorations.
• Often allow a conservative preparation design.

Composite restorations require appropriate moisture control and careful placement. Their longevity depends on the size of the restoration, location, biting forces and oral habits.

2. Glass ionomer cement (GIC) fillings

Glass ionomer cement is a tooth-coloured restorative material that chemically bonds to tooth structure and releases fluoride over time.

• Fluoride release is a useful material property.
• Can be useful in selected cervical lesions and areas where moisture control is challenging.
• Commonly used in certain paediatric and interim restorative situations.

Conventional GIC generally has lower wear resistance and strength than composite resin, so the choice of material should suit the location and functional demands of the restoration.

3. Amalgam fillings

Dental amalgam is a metallic restorative material that has historically been used for posterior teeth because of its durability and wear resistance. It has a silver-coloured appearance and does not match the natural tooth shade.

Its use has declined in many settings due to aesthetic preferences and environmental and regulatory considerations. Material selection should follow current local regulations and clinical recommendations.

4. Indirect restorations: inlays and onlays

When a cavity or fracture is too extensive for a predictable direct filling, an indirect restoration may be considered. Inlays and onlays are fabricated outside the mouth and then bonded or cemented to the prepared tooth.

They may be made from ceramic or other suitable restorative materials. The decision depends on the remaining tooth structure and the functional requirements of the tooth.

What is a tooth-coloured composite filling?

Composite resin is a popular option for many modern dental restorations because it can be matched to the natural colour of the tooth.

The material is generally placed in the prepared cavity, adapted to the required shape and hardened using a curing light. The dentist then checks the bite and polishes the restoration.

A well-placed composite filling can restore both appearance and function. However, no filling material lasts forever, and all restorations require regular review.

How is a dental filling done?

A routine filling is usually completed in a single appointment. The exact steps depend on the size and depth of the cavity and the material selected.

1. Examination and diagnosis

Your dentist examines the tooth and may recommend an X-ray if needed to assess the extent of decay or check areas that cannot be seen directly.

2. Local anaesthesia, if required

For deeper cavities or when sensitivity is expected, local anaesthesia may be given to keep the procedure comfortable. Very small restorations may not always require an injection.

3. Removal of decay and tooth preparation

The dentist removes infected or unsuitable tooth structure as clinically indicated and prepares the area for restoration.

4. Placement of filling material

The selected material is placed and adapted to restore the missing tooth structure. Composite restorations involve an adhesive bonding protocol and light curing.

5. Bite adjustment and polishing

The dentist checks your bite to make sure the filling does not interfere with normal chewing. The restoration is then finished and polished as appropriate.

Does getting a dental filling hurt?

Most dental fillings are straightforward procedures. Some patients may experience vibration, pressure or mild sensitivity during treatment. Local anaesthesia can be used when necessary to make the procedure comfortable.

After treatment, temporary sensitivity to cold, heat or biting pressure may occur, particularly with deeper restorations. This usually improves, but persistent or worsening pain should be assessed by your dentist.

How should you care for your teeth after a filling?

Good oral hygiene and regular dental reviews help protect both your natural teeth and your restorations.

• Brush twice daily using a fluoride toothpaste.
• Clean between your teeth daily using floss or suitable interdental aids.
• Limit frequent sugary snacks and drinks.
• Follow your dentist's advice about eating after treatment, especially while the anaesthesia is still active.
• Avoid biting very hard objects with a newly restored tooth.
• Attend regular dental check-ups to monitor the filling.

How long do dental fillings last?

The lifespan of a filling varies. It depends on the material, the size and location of the restoration, chewing forces, oral hygiene and habits such as teeth grinding.

Small restorations may remain functional for many years, while larger restorations may require repair or replacement sooner. There is no guaranteed lifespan for any filling material.

Your dentist can check for cracks, marginal breakdown, recurrent decay and changes in the bite during routine examinations.

When should you replace a dental filling?

A filling does not need to be replaced simply because it is old. Replacement or repair may be recommended if there is evidence of:

• Fracture or loss of part of the filling.
• Recurrent decay around or beneath the restoration.
• Marginal defects that cannot be managed conservatively.
• Persistent symptoms associated with the restored tooth.
• Significant wear or a compromised restoration.

Whenever possible, repairing a defective restoration may preserve more healthy tooth structure than replacing the entire filling. The appropriate approach depends on clinical assessment.

Frequently asked questions

Final thoughts

Dental fillings are an effective way to restore many teeth affected by decay or minor damage. Early diagnosis and suitable restorative treatment can help preserve natural tooth structure and maintain comfortable chewing.

Do not wait for a cavity to become painful. Regular dental check-ups can help identify problems early, when treatment may be simpler and more conservative.

This article is for general patient education and does not replace a clinical examination, diagnosis or individual treatment advice.