If you’ve been told you need a dental filling, you might be wondering: What fillings do dentists use, and why?
Dentists use various types of fillings depending on your needs, including composite (white), amalgam (silver), ceramic, glass ionomer, and gold. Each material has different strengths, aesthetics, and durability. Your dentist will recommend the best option based on the tooth’s location, cavity size, budget, and your personal preferences.
From tooth-coloured composites to traditional silver amalgam and modern ceramics, there are several options available. Each filling material has its strengths, limitations, and purpose, and the right choice often depends on where the cavity is, how large it is, your oral health, and your personal preferences.
At Diamond Smile, we believe in clear, honest advice tailored to your needs. In this guide, we’ll explain:
- The different types of fillings dentists use
- What each material is made of
- Pros and cons of each option
- Typical costs and lifespans
- When each type is most appropriate
Why Are Fillings Needed?
Fillings are one of the most common dental treatments, and for good reason.
They help to:
- Restore areas of the tooth lost to decay, wear, or injury
- Seal the area to prevent further damage
- Rebuild the function so you can chew comfortably
- Improve the aesthetics of the tooth when needed
Most commonly, fillings are used to treat cavities. These are tiny holes caused by decay when plaque bacteria break down enamel. But fillings are also used for:
- Repairing chipped teeth
- Restoring worn-down surfaces from grinding
- Replacing old or broken fillings
- Cosmetic reshaping in some cases (with composite)
Early treatment is key. The smaller the filling, the better the long-term outcome.
What Fillings Do Dentists Use?
Dentists use several different filling materials, each suited to different situations. Here’s a breakdown of the most common types, including what they’re made from, how long they last, and when they’re typically used.
1. Composite Fillings (White Fillings)
Material: A blend of tooth-coloured plastic resin and fine glass particles
Colour: Matches natural tooth colour
Where it’s used: Front and back teeth
Composite fillings are one of the most popular choices in modern dentistry, especially for patients seeking aesthetic, discreet restorations.
Pros:
- Blends in naturally with your tooth colour
- Bonds to the tooth, preserving more of the original structure
- Less drilling required
- Versatile, can be used to reshape teeth or close gaps
Cons:
- Less durable than metal fillings in high-pressure areas
- May stain over time (like natural teeth)
- Not always suitable for very large cavities
Typical lifespan:
5–10 years, though well-maintained fillings can last longer with good oral hygiene and bite protection.
2. Amalgam Fillings (Silver Fillings)
Material: A mix of metals, primarily silver, tin, copper, and liquid mercury
Colour: Metallic silver-grey
Where it’s used: Molars and back teeth, especially in high-bite-pressure zones
Amalgam fillings have been used for over 150 years. They’re durable, reliable, and cost-effective, which is why they’re still commonly used, particularly under NHS dentistry.
Pros:
- Extremely durable and strong
- Withstands heavy chewing forces
- Cost-effective
- Long history of use in dentistry
Cons:
- Highly visible (not tooth-coloured)
- Mercury content raises concerns for some patients (though studies show they’re safe when placed correctly)
- May expand/contract with temperature, leading to microfractures in rare cases
Typical lifespan:
10–15 years, often longer
Note: Amalgam is gradually being phased out in some countries for environmental reasons, but it is still used safely in many UK practices.
3. Ceramic Fillings (Porcelain / Inlays / Onlays)
Material: High-strength porcelain
Colour: Tooth-coloured
Where it’s used: Back teeth, larger restorations, aesthetic cases
Ceramic fillings, also called inlays or onlays, are made outside the mouth in a dental lab or in-house using CAD/CAM technology. They’re bonded to the tooth for a strong, long-lasting result.
Pros:
- Extremely durable and wear-resistant
- Natural appearance, very aesthetic
- Highly resistant to staining
- Well-suited for patients with metal allergies
Cons:
- Higher cost than composite or amalgam
- Requires more than one visit (unless same-day milling is available)
- Less conservative than composite, more tooth may need to be prepared
Typical lifespan:
10–15+ years with excellent care
4. Glass Ionomer Fillings
Material: A combination of acrylic and glass powder
Colour: Tooth-coloured (but less aesthetic than composite)
Where it’s used: Baby teeth, low-pressure areas, or short-term fillings
These are often used for children’s teeth or in areas where cosmetics are not a priority. They’re also used as a base or liner beneath composite fillings.
Pros:
- Releases fluoride, helping prevent further decay
- Easy to place, quick application
- Better tolerated by sensitive or young patients
Cons:
- Less durable, prone to wearing down
- Not suitable for high-stress areas
- The aesthetic result is not as natural as composite or ceramic
Typical lifespan:
3–5 years
5. Gold Fillings (Cast Gold Inlays/Onlays)
Material: Gold alloy
Colour: Bright gold
Where it’s used: Mostly in molars and non-visible areas
Though not as commonly used today, gold fillings are still available, especially in private practices, for patients who prioritise long-term durability and biocompatibility.
Pros:
- Incredibly long-lasting, can outlast other materials
- Doesn’t corrode
- Biocompatible (doesn’t irritate the gum or tissue)
Cons:
- Very visible
- Higher cost than most other options
- Requires at least two appointments
Typical lifespan:
15–30+ years
6. Temporary Fillings
Material: Soft or semi-hard composite-like materials
Purpose: Short-term solution while a tooth heals or before a permanent restoration
Temporary fillings are used in:
- Emergency appointments
- After root canal treatment
- As an interim step before a permanent filling, crown, or veneer
These are not meant to last long and should be replaced within a few weeks to prevent leakage or infection.
How Do Dentists Choose Which Filling to Use?
At Diamond Smile, we never take a one-size-fits-all approach. We recommend fillings based on:
- Tooth location – back teeth need more durable materials; front teeth need aesthetics
- Size and depth of the cavity – larger cavities may need stronger restorations like ceramic or onlays
- Your bite pressure – grinders may need reinforced materials
- Your cosmetic goals – visible areas usually call for tooth-coloured options
- Allergies or sensitivities to certain metals or ingredients