A dental filling repairs a tooth that has lost structure to decay, a crack or ordinary wear. We take out the damaged part, clean the tooth and rebuild it with tooth-coloured composite bonded into place.
Composite fillings are placed in one appointment. No referral needed, and you do not need to be a patient here already.
How do you know you need a filling?
Most cavities are found before you feel anything, at a check-up or on an x-ray.
When you do notice something, it is one of these:
- Sensitivity to cold, heat or sweet things that lingers after the mouthful
- A dark spot, a grey shadow or a hole you can see
- Food packing into the same place every time you eat
- A rough or chipped edge your tongue keeps finding
- An ache when you bite down on one particular tooth
None of these proves a cavity. All are worth an appointment. Read about exams and check-ups.
What happens if you leave it
Decay in the dentine does not repair itself. Left alone it works inwards towards the nerve.
A small filling can turn into a large one and then into a crown. If the nerve becomes infected, the tooth needs root canal treatment or comes out.
Treating it early is the smaller job.
What happens at your filling appointment
- A look at the tooth, with images where they are needed.
- The plan and the cost, before anything starts.
- Numbing, where the tooth needs it.
- Removing the decay and shaping what is left of the tooth.
- Placing the composite in layers and hardening each one.
- Checking your bite and adjusting it before the filling is polished smooth.
- Rebuilding the contact with the next tooth, where the filling reaches that far.
The contact point matters more than it sounds. A filling that does not rebuild the tight point against the next tooth lets food pack in, which irritates the gum and raises the risk of decay. Tell us if food starts catching.
Can it be done the same day? Often, yes. If there is not much to do we get on with it at the same visit, and the dentist decides that after looking.
Need a filling booked? Call (905) 821-8632 or book online.
Does a dental filling hurt?
The injection is the part most people mind and it is over in seconds.
After that you should feel pressure and vibration rather than pain. Say so if anything feels sharp. We stop, work out why, and top up the freezing where that is the right answer.
After your filling
Numbness usually lasts a few hours. Do not chew on that side until it wears off. Biting a numb cheek is easy and it hurts for days.
Once feeling is back you can eat as normal. The curing light sets a composite hard before you get up from the chair. Cleveland Clinic says eating and drinking straight after a filling is fine.
A sore gum and mild sensitivity to cold are normal after a filling. The same Cleveland Clinic page expects both to go away in a week or two. Acetaminophen or ibuprofen helps with the soreness if those medicines are safe for you. Sensitivity that is severe, or that lingers after the cold goes, needs a call.
If your bite feels high, say so. A filling sitting slightly proud aches when you chew and bruises the ligament holding the tooth. Do not put up with it.
Pain that builds over days is different. So is a tooth that throbs on its own. Neither is part of healing.
Call us the same day if there is swelling, a fever, or a bad taste that will not shift. Call 911 if you have difficulty breathing or swallowing, are drooling because you cannot manage your saliva, your voice has changed or sounds muffled, or you feel confused or faint.
A tooth that was already deeply decayed can need more than a filling.
What dental fillings are made of
Tooth-coloured composite is the standard choice here. It bonds to the tooth and it is shaded to match. It repairs chipped and worn edges as well as cavities. White fillings and composite fillings are the same thing.
We place the others too, where they suit a tooth better: amalgam, glass ionomer, gold and porcelain.
Composite is plastic and glass compounds. A CADTH health technology assessment describes amalgam as about half mercury mixed with silver, tin and copper.
Glass ionomer releases fluoride and is used where keeping the area dry is hard. StatPearls lists baby teeth and lesions at the gumline among its uses. It is weaker than composite, so it stays off the heavy chewing surfaces of adult back teeth. It also goes under a composite or amalgam as a protective lining in a deep cavity.
Amalgam is the silver metal, and the most durable direct filling there is. It hardens fast. The ADA says that suits spots that are hard to keep dry. Who should not have it placed is covered below.
Porcelain and gold are inlays and onlays, covered below.
When a filling is not enough: inlays and onlays
Some cavities are too big for a filling and too small to justify cutting the tooth down for a crown. Inlays and onlays fill that gap.
Both are made outside the mouth in porcelain or gold, then bonded on. An inlay sits inside the cusps of a back tooth. An onlay covers the cusps too, which is what a cracked or undermined corner needs.
They take two appointments: one to prepare the tooth and take an impression, one to fit the finished restoration.
Why not just place a large filling? A big filling in a molar flexes under load and the tooth can split. An onlay holds the cusps together instead of wedging them apart.
Which one a tooth needs comes down to how much sound tooth is left.
Should you replace your silver fillings?
Not for being silver.
Health Canada's 1996 position statement says that "current evidence does not indicate that dental amalgam is causing illness in the general population", and that the evidence "does not warrant the removal of existing amalgam fillings from individuals who have no indications of adverse effects". Health Canada says an updated risk assessment completed in 2020 affirms those recommendations.
It does give advice on placing new amalgam. Not where kidney function is impaired and not where there is a mercury allergy. Consider non-mercury materials for children's baby teeth. Avoid placing or removing it during pregnancy where possible.
An old filling gets replaced when it has worn or fractured, when decay starts underneath or when the tooth around it cracks. Wanting a tooth-coloured repair is a fair reason too.
How long does a dental filling last?
Years, and no filling lasts forever. A 2025 systematic review put the median at about 11 years for composite and over 16 for amalgam, with decay at the edge the commonest reason a composite gets replaced.
Porcelain inlays and onlays hold up well too. A 2016 meta-analysis estimated 91% still in service at 10 years, and fracture was the main cause of failure.
Grinding wears one down fastest. So does chewing ice, opening packets with your teeth and a diet heavy in sugar or acid.
What makes one last is dull, not clever. The brushing and flossing that stops the next cavity, and a check-up that spots a worn edge early.
Book a look if a filling feels rough or chipped, has changed colour or keeps trapping food. Healthdirect notes that fillings chip, wear and discolour over time. A sharp pain on biting is a reason to come in as well.
Fillings get replaced when they fail, not on a schedule. If one comes out and the tooth is comfortable, it is not an emergency but it does need an appointment. Read about a lost filling or crown.
What a dental filling costs in Mississauga
Material and size drive the number. These are the ranges you will see in this area.
| Filling | Typical range |
|---|---|
| Silver amalgam | $120 to $395 |
| Composite resin, tooth-coloured | $150 to $498 |
| Glass ionomer | $116 to $285 |
| Inlay or onlay | $400 to $1,417 |
Amalgam is cheapest and it is silver. Composite costs more and matches the tooth. The inlay range is wide because it runs from a small inlay to a large onlay.
What moves you inside a range: how many surfaces are involved, where the tooth sits and whether x-rays are needed. Other treatment needed first changes it too.
Priced by the surface
A tooth has five surfaces a filling can cover: the chewing top, the front, the back and the two sides that touch the next teeth. A small pit on the top is a one-surface filling. Decay that starts between two back teeth and is reached through the top makes two. Each extra surface is more time and more material, so the fee climbs with the count.
Published Ontario price lists put a one-surface composite at $150 to $250. Two or more surfaces come to $200 to $400.
Front and back teeth are priced apart too. A molar is harder to reach and to isolate from saliva than a front tooth.
A new-patient visit that finds the cavity also has an exam and x-rays. Ask whether a quote you are comparing counts them or leaves them out. Ask the same about the freezing. Area fees for exams and x-rays are set out on the exams and check-ups page.
Those are figures for the area rather than a list of ours. Yours is written down before treatment begins. Direct insurance billing applies, and the Canadian Dental Care Plan is open to all ages for eligible Canadian residents; eligibility requires no access to private dental insurance, the required Canadian tax returns, adjusted family net income under $90,000, and Canadian residency for tax purposes, so the cost need not be guesswork.
Read about coverage and the CDCP.
Dentistry on Britannia is a general dental practice. Our dentists are general dentists, not specialists in any RCDSO-recognised specialty.