Dental fillings are one of the most common treatments in general dentistry, used to restore teeth affected by decay, cracks, or wear. While they’re made to last, no filling is permanent. Over time, your old fillings can begin to wear down, loosen, or even leak — which can leave your tooth vulnerable to further damage.
If you’ve had the same fillings for many years, it might be time to consider an upgrade. Here’s why older fillings may need replacing, how to spot the signs, and what your modern options are.
What Are Dental Fillings Made From?
There are two main types of fillings commonly used in dentistry:
- Amalgam (silver) fillings: Durable and long-lasting, amalgam fillings have been used for over a century. However, they can expand and contract with temperature changes, which may cause fractures over time. Their dark colour also makes them more noticeable in the mouth.
- Composite (white) fillings: These tooth-coloured fillings are made from a blend of plastic and fine glass particles. They are bonded directly to the tooth and offer a more natural appearance. While not quite as durable as amalgam, they are ideal for small to medium restorations, especially on visible teeth.
Why Fillings Don’t Last Forever
Although fillings are designed to be strong, they are constantly exposed to the pressures of chewing, grinding, and changes in temperature. Over time, this wear and tear can cause fillings to:
- Chip or crack
- Loosen or fall out
- Separate from the surrounding tooth (microleakage)
- Allow bacteria to enter and cause new decay beneath the filling
The average lifespan of a filling is:
- Amalgam: 10–15 years
- Composite: 5–10 years
However, with excellent care, some fillings may last longer — while others may need replacing sooner if there’s damage or recurrent decay.
Signs Your Fillings May Need Replacing
You may not always feel when a filling starts to fail, which is why regular dental check-ups are so important. Still, here are some common warning signs:
- Sensitivity to hot, cold, or sweet foods
- Sharp pain when biting down
- Visible cracks or chips
- A filling that feels loose or rough
- Discolouration or dark edges around the filling
- Food getting caught in the area
Even if your filling feels fine, small leaks or fractures may only be visible through dental X-rays or an in-clinic examination.
The Risks of Delaying Treatment
An old or damaged filling isn’t just a cosmetic issue — it can lead to more serious problems if left untreated. A loose filling can allow bacteria to sneak in underneath, causing new decay or infection. This may result in:
- Larger cavities
- Nerve damage requiring root canal treatment
- Tooth fracture or loss
Replacing a compromised filling promptly helps preserve the tooth’s structure and prevents more complex treatment down the track.
Modern Materials, Better Results
Today’s dental materials have come a long way. Modern composite fillings are more durable, more natural-looking, and better bonded to the tooth than ever before. Upgrading your old fillings can offer several benefits:
- Improved appearance: Replacing silver fillings with tooth-coloured ones creates a more natural, seamless look.
- Better fit: Composite materials are bonded directly to the tooth, which can strengthen the remaining tooth structure.
- Reduced risk of cracks: Newer materials are less likely to expand and contract with heat and cold, reducing stress on the tooth.
For larger fillings or teeth under heavy chewing pressure, options like inlays, onlays, or crowns may be more suitable. We’ll always recommend the option that provides the best long-term outcome for your tooth.
The Process of Replacing a Filling
Upgrading a filling is typically straightforward:
- The old filling is gently removed.
- The tooth is examined and cleaned to remove any hidden decay.
- A new filling is placed and shaped to match your bite.
- The filling is hardened (if composite) and polished for a smooth finish.
The entire process is usually completed in a single appointment, and local anaesthetic is used to ensure your comfort throughout.
Prevention Is Better Than Cure
Regular dental visits allow us to keep a close eye on your existing fillings and address issues early. Maintaining good oral hygiene at home also helps extend the life of your dental work.
- Brush twice a day with fluoride toothpaste
- Floss daily to remove plaque between teeth
- Avoid biting hard objects like ice or pens
- Wear a night guard if you grind your teeth at night
If it’s been a while since your last check-up, or if you’re noticing changes in your existing fillings, we invite you to come visit us. We’ll assess your restorations and recommend the best steps to keep your smile strong, healthy, and looking its best.