A composite filling repairs a tooth damaged by decay with a tooth-coloured resin that is bonded to the tooth and hardened with a blue light. It is usually done in one visit of about 20 to 60 minutes under local anaesthesia, and with good care it commonly lasts many years.
What a composite filling is and when you need one
Tooth decay, or a cavity, happens when bacteria in plaque turn sugars into acids that dissolve the enamel, the hard outer layer of the tooth, and then the softer dentine beneath it. Once a hole has formed, the tooth cannot repair it; a filling removes the decayed part and seals the tooth with a durable material.
Composite is a tooth-coloured mixture of resin and fine glass or ceramic particles, also used for composite bonding to repair chips and small gaps. Because it bonds to the tooth, less healthy tooth usually needs to be removed than for the older silver fillings.
Signs you may need a filling
Early decay is often painless, which is why many cavities are found at regular dental check-ups. Signs worth having checked include:
- a brief twinge in one tooth with sweet, cold or hot food and drink (sensitivity has other causes too; see our guide to tooth sensitivity to cold and heat);
- food catching between two teeth, or floss that shreds in the same place;
- a dark spot, a chalky white patch or a hole you can feel with your tongue;
- a rough edge, a broken piece of tooth or old filling, or pain when biting.
The procedure step by step
A composite filling usually takes a single visit of roughly 20 to 60 minutes per tooth, depending on the size and position of the cavity.
- Examination: the dentist checks the tooth and, when needed, takes an X-ray to see how deep the decay goes.
- Numbing: local anaesthesia, an injection that numbs the tooth and the area around it, is given when the decay reaches the dentine; a numbing gel applied first makes it feel like a small pinch.
- Keeping the tooth dry: cotton rolls or a thin rubber sheet isolate the tooth, because composite only bonds well to a clean, dry surface.
- Removing the decay: only the soft, decayed part is removed, and the cavity is shaped.
- Bonding and layering: a mild gel and a liquid bonding agent prepare the surface, then composite in a shade matched to your tooth is placed in thin layers, each hardened with a blue curing light.
- Finishing: the filling is shaped and polished, and your bite is checked with thin coloured paper.
Anaesthesia, pain and sensitivity afterwards
With local anaesthesia, you feel pressure, vibration and water, but not pain; small, shallow cavities can sometimes be filled without an injection. The numbness lasts a few hours, so avoid chewing and hot drinks until it wears off. The composite itself is fully hardened before you leave.
Mild sensitivity to cold or when biting is common for a few days and usually fades within one to two weeks, as Cleveland Clinic explains in its overview of dental fillings. Contact the dentist if the tooth feels high when you bite, if pain with hot or cold lingers for a minute or more, or if throbbing pain appears on its own. When decay was very close to the nerve, the nerve sometimes does not recover, and root canal treatment may be needed later.
Old silver (amalgam) fillings: replace them or keep them?
Many adults still have silver-coloured amalgam fillings, a mixture of metals that includes mercury. Mainstream dental organisations consider intact amalgam fillings safe for most people and do not recommend removing them just because they are amalgam: drilling out a sound filling removes healthy tooth and briefly releases mercury vapour.
Replacing an amalgam filling with composite makes sense when:
- the filling is cracked, broken or badly worn;
- there is new decay at its edges or underneath it;
- the tooth around it is cracked;
- it is clearly visible and you prefer a tooth-coloured result, after discussing it with your dentist.
How long composite fillings last
Well-placed composite fillings commonly last many years, often around five to ten years and frequently longer. Their lifespan depends mainly on:
- size, as small fillings usually outlast large ones;
- position, as back teeth carry more chewing force;
- grinding or clenching, against which a night guard can help;
- new decay at the edges, linked to diet and daily cleaning;
- check-ups, which catch small problems early.
Composite can stain over time from coffee, tea and smoking, and it does not lighten with whitening, so whitening is usually done before visible fillings are replaced.
When an inlay, onlay or crown is the better choice
A filling relies on the surrounding tooth for its strength. When much of the tooth is missing, a large filling can crack or the tooth itself may break, so a stronger, custom-made restoration is often wiser. Our guide to inlays and onlays, the middle ground between a filling and a crown, explains that option.
| Option | Usually suited to | Visits |
|---|---|---|
| Composite filling | Small to medium cavities | Usually one |
| Inlay or onlay | Larger cavities, or lost cusps (the raised points of a back tooth) | Usually two |
| Crown | Badly broken or cracked teeth, and many back teeth after root canal treatment | Usually two |
See also our article on dental crowns and when you need one.
What determines the cost
The cost of a composite filling is set after an examination. The main factors are:
- the size of the cavity and the number of tooth surfaces involved;
- the number of teeth to treat, and whether X-rays are needed;
- whether an old filling has to be removed first;
- whether further treatment, such as root canal treatment or an onlay, is needed.
Composite fillings at Ajam Dental Clinic in Tripoli
Ajam Dental Clinic offers composite (tooth-coloured) fillings as part of its preventive and general dental care. Fillings for babies, children and teenagers are carried out by Dr. Soumaya Ajam, whose specialty is paediatric dentistry; see also whether cavities in baby teeth should be treated. Crowns are part of the focus of Dr. Abdel Rahman Ajam, and root canal treatment is carried out at the clinic by a visiting specialist endodontist.
Patients come to our clinic on Fouad Chehab Boulevard from across Tripoli — Al-Qobbeh, Bab al-Tabbaneh, Jabal Mohsen and Dam wa Farez — as well as from Beddawi, Minieh and the rest of North Lebanon. If a tooth has started to twinge or an old filling feels rough, contact us to book a consultation.
Frequently asked questions
Can I eat straight after a composite filling?
As far as the filling itself is concerned, yes. Composite is fully hardened by the curing light before you leave the chair, so, unlike some older materials, it does not need hours to set. The limit is the anaesthesia: while your lip, cheek or tongue is still numb, it is easy to bite them or burn yourself without noticing. Wait until the feeling has fully returned, usually after a few hours, before eating or having hot drinks. For the first day or two, if the tooth feels a little sensitive, choose lukewarm food and chew mostly on the other side.
Is a white filling as strong as a silver one?
Modern composites are strong enough for most fillings in both front and back teeth, and because they bond to the tooth they help support what remains of it. Amalgam has a long track record, and in very large fillings on heavily loaded back teeth it can sometimes last longer. Composite is also more demanding to place, because the tooth must be kept dry throughout. For very large cavities, neither material may be ideal, and an onlay or a crown is often the stronger option. Your dentist will explain what suits each tooth.
Will my filling match the colour of my teeth?
The dentist chooses a shade from a range of composite colours to blend with your tooth, and the filling is polished to a natural shine. On back teeth it is usually very hard to see. Over the years, composite can pick up some staining from coffee, tea or smoking, and its edges may darken slightly; a professional polish can often improve this. Keep in mind that whitening products do not lighten fillings, so if you plan to whiten your teeth, mention it before visible fillings are placed.
Does every small cavity need a filling?
Not always. Very early decay may appear as a chalky white or light brown patch on the enamel without an actual hole. At this stage, the surface can sometimes harden again with fluoride toothpaste, a fluoride varnish applied at the clinic, less frequent sugar and careful cleaning, and the dentist simply watches the area at your next check-ups. Once decay has broken through the enamel and reached the dentine, it no longer heals by itself and usually keeps growing, so a filling is recommended before it comes close to the nerve.
Can I have a filling during pregnancy?
In most cases, yes. Routine dental treatment such as fillings is generally considered safe during pregnancy, and treating decay is better than leaving a source of infection in the mouth. The local anaesthetics commonly used in dentistry are considered appropriate for pregnant women at usual doses. Many women find the middle months of pregnancy the most comfortable time for non-urgent treatment. Always tell the dentist that you are pregnant and mention any medicines you take; X-rays are taken only when they are really needed.
What should I do if my filling falls out or breaks?
Try not to worry: a lost or chipped filling is rarely an emergency unless there is severe pain or swelling. Keep the area clean by brushing gently and rinsing after meals, and chew on the other side. Avoid very sweet, hard or sticky foods, which can get trapped in the gap or damage the tooth further. If the tooth is sensitive, a toothpaste for sensitive teeth can help for a few days. Book an appointment soon, because an open cavity collects food, decay can progress, and a sharp edge may hurt your tongue.
Have a question about your teeth?
Send a WhatsApp message to Dr. Abdel Rahman Ajam or Dr. Soumaya Ajam, or call the clinic to book a consultation.
This article provides general information for patients. It does not replace an examination by a dentist, who can advise you on your own situation.
