Dental Fillings vs Inlays: Which Is Right for You?
Both fillings and inlays repair damaged teeth — but the right choice depends on the size of the cavity and the strength your tooth needs. Understanding the difference helps you feel more informed about your options.
When you need a tooth repaired, you may wonder whether a standard white filling in London is sufficient or whether a stronger, laboratory-crafted inlay would be the better option. Both are effective solutions — but they are designed for different levels of tooth damage.
This guide explains the key differences between dental fillings and inlays — covering strength, fabrication, cost, and longevity — so you can understand which approach may be most appropriate for your tooth. The right option will always depend on a thorough clinical assessment by your dentist.
The information on this page is for general guidance only. Treatment suitability, outcomes, and costs vary between individuals. A clinical examination is necessary before any treatment can be recommended.
Dental Fillings vs Inlays: Side-by-Side
A quick overview of the key differences between composite fillings and dental inlays.
| Feature | Composite Filling | Dental Inlay |
|---|---|---|
| Coverage of Tooth | Fills the cavity directly — partial repair | Custom-fitted within the cusps of the tooth |
| Procedure Type | Direct — placed and shaped chairside | Indirect — fabricated in a dental laboratory |
| Treatment Time | Single appointment — typically 30–60 minutes | Usually two appointments over 1–2 weeks |
| Strength | Suitable for small to moderate restorations | Stronger — ideal for moderate to large cavities |
| Aesthetics | Tooth-coloured composite resin | Tooth-coloured porcelain or ceramic |
| Cost (UK Range) | From £185 | From £995 |
| Longevity | Typically 5–10 years depending on size and location | Typically 10–15+ years with good care |
| Suitability | Small to moderate cavities and minor damage | Moderate to large cavities needing greater strength |
This table provides a general overview. The most suitable option depends on your individual clinical assessment.
What Are Dental Fillings?
A dental filling is a direct restoration used to treat tooth decay with fillings — repairing a cavity by filling the affected area with tooth-coloured composite resin. The filling material is placed directly into the prepared cavity, shaped to match the natural contours of the tooth, and hardened with a curing light — all in a single appointment.
Modern white composite fillings are mercury-free, aesthetically natural, and an effective solution for small to moderate cavities. They are one of the most common and affordable restorative treatments in dentistry.
Potential Benefits
- Completed in a single appointment — no second visit needed
- Preserves natural tooth structure — only decay is removed
- Tooth-coloured and mercury-free
- Affordable and cost-effective for smaller restorations
- Bonds directly to the tooth for a secure repair
Suitable Candidates May Include
- Patients with small to moderate cavities from decay
- Those with minor chips or wear on a tooth
- Patients wanting to replace old amalgam (silver) fillings
- Those seeking an affordable, single-visit restoration
Your dentist will confirm whether a filling provides adequate support for your specific case.
What Are Dental Inlays?
A dental inlay is an indirect restoration — a custom-made piece fabricated in a dental laboratory and then bonded into the prepared cavity. Unlike a filling, which is shaped directly in the mouth, an inlay is precisely crafted outside the mouth from materials such as porcelain or ceramic, resulting in a stronger, more durable restoration.
Inlays sit within the cusps (raised edges) of a tooth, making them ideal for moderate to large cavities where a standard filling may not provide adequate long-term strength. Treatment typically requires two appointments — one to prepare the tooth and take impressions, and a second to fit the inlay. A dental examination for treatment planning will determine whether an inlay is the most appropriate restoration for your case.
Potential Benefits
- Stronger and more durable than a composite filling
- Custom-made for a precise, accurate fit
- Resistant to wear — designed for long-term function
- Tooth-coloured porcelain or ceramic for natural aesthetics
- Ideal for moderate to large cavities in back teeth
Suitable Candidates May Include
- Patients with moderate to large cavities too big for a standard filling
- Those needing a strong restoration for back teeth (premolars, molars)
- Patients replacing large failing fillings with a more durable option
- Those who want a long-lasting, laboratory-crafted restoration
Your dentist will confirm whether an inlay is the most suitable restoration for your tooth.
How Do They Compare?
Understanding these differences helps clarify when a filling is sufficient and when an inlay is the more appropriate choice.
Coverage and Strength
Fillings are placed directly into the cavity and shaped by hand, which works well for smaller restorations. Inlays are precision-crafted in a laboratory, resulting in a harder, more wear-resistant restoration — better suited to larger cavities and teeth that bear heavy biting forces.
Fabrication Process
Fillings are a direct restoration — composite resin is placed, shaped, and cured chairside in a single visit. Inlays are indirect — impressions are taken and the restoration is custom-fabricated in a dental laboratory before being bonded to the tooth at a second appointment.
Longevity
Inlays are generally expected to last longer than composite fillings — typically 10 to 15 years or more, compared to 5 to 10 years for fillings. The laboratory fabrication process produces a denser, more durable material that is better equipped to withstand daily wear.
Cost
Fillings are significantly more affordable, as they involve no laboratory costs and are completed in a single appointment. Inlays cost more due to the laboratory fabrication, premium materials, and the two-appointment process — but they may prove more economical long-term for larger cavities.
Suitability Based on Cavity Size
For small to moderate cavities, a composite filling is typically the most appropriate and cost-effective option. For moderate to large cavities — particularly in back teeth — an inlay provides greater strength and longevity. Your dentist will assess which option is right based on the extent of the damage.
Pros and Cons
Both serve an important role in restorative dentistry. Here is a balanced overview of each option.
Dental Fillings
Direct chairside restoration for cavities
Pros
- Affordable and cost-effective for smaller restorations
- Completed in a single appointment
- Preserves natural tooth structure — minimal preparation
- Tooth-coloured and mercury-free
- Effective for treating small to moderate decay
Cons
- Shorter expected lifespan than inlays
- May chip, wear, or stain over time
- Less suitable for large cavities in back teeth
- Large fillings are more prone to fracture under biting forces
Dental Inlays
Laboratory-crafted restoration for greater strength
Pros
- Stronger and more wear-resistant than composite fillings
- Custom-made for a precise, accurate fit
- Longer expected lifespan — typically 10–15+ years
- Tooth-coloured porcelain or ceramic
- Ideal for larger cavities in back teeth
Cons
- Higher cost than a composite filling
- Requires two appointments to complete
- Involves a temporary filling between visits
- Not necessary for small cavities where a filling is sufficient
Cost Comparison
Costs vary depending on the treatment needed and individual clinical factors.
Composite Filling
From £185
Per filling
Composite fillings are one of the most affordable restorative treatments available. They are completed in a single visit with no laboratory costs, making them an excellent value option for smaller cavities and minor repairs.
Final cost confirmed at your appointment. Larger restorations may cost more.
Dental Inlay
From £995
Per inlay
The cost of an inlay reflects the laboratory fabrication, premium porcelain or ceramic materials, and the two-appointment process. While the upfront cost is higher, inlays offer greater durability — which may make them more economical over the longer term for suitable cases. For larger cavities, a dental crown in London may be an alternative if full coverage is needed.
Final cost confirmed after consultation. Individual cases may vary.
Final costs are confirmed after your consultation and clinical assessment. A full written estimate is always provided before treatment begins.
See full treatment feesWhich Option May Be Best for You?
Your dentist will recommend the most appropriate option based on a thorough clinical examination. These general scenarios may help guide your understanding.
Best for Small Cavities
If the cavity is small and the tooth retains most of its structure, a composite filling is typically the most appropriate and cost-effective option. It can be completed quickly in a single visit and provides a reliable repair for minor damage.
Best for Moderate Tooth Damage
If the cavity is moderate to large — particularly in a back tooth — an inlay provides a stronger, more durable restoration. Its laboratory fabrication allows for a more precise fit and greater resistance to the biting forces that back teeth endure.
Best for Durability
When long-term durability is a priority, inlays typically outperform composite fillings. Their harder, more wear-resistant materials are designed to last 10 to 15 years or more, making them a sound long-term investment for larger restorations.
Best for Affordability
If cost is a key consideration and the damage is relatively minor, a composite filling offers an effective and affordable solution. It can be completed in a single visit with no laboratory costs, making it the most budget-friendly option for suitable cases.
The Right Choice Starts with an Assessment
The decision between a filling and an inlay is not one you need to make alone. During your dental examination, your dentist will assess the size of the cavity, the condition of the remaining tooth, and your overall dental health. They will then recommend whichever option — or combination of tooth restoration options — is most clinically appropriate for your case. For very large cavities, a long-term tooth restoration such as a crown may be considered, or you may wish to explore broader smile improvement options depending on your goals.
Your dentist will recommend the most suitable restoration following a thorough clinical assessment.
Frequently Asked Questions
Not Sure Whether You Need a Filling or an Inlay?
Book a consultation with one of our experienced dentists. Following a thorough clinical examination, your dentist will explain which option — a filling, an inlay, or an alternative restoration — is most appropriate for your tooth and provide a full written estimate before any treatment begins.
This article is intended for general educational purposes only and does not constitute personalised dental advice. Individual diagnosis and treatment recommendations require a clinical examination by a qualified dental professional. Treatment outcomes, timelines, and costs vary between individuals. All treatments are provided by GDC-registered dental professionals at our CQC-registered practice.
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