No two people who come to us about whitening have the same tooth color. Some already have fairly white teeth and want them brighter. Others feel their teeth are yellow, dull, or blotchy and hold back when they smile. We understand that everyone wants white teeth quickly. But before you pick a fix, it helps to know why your teeth changed color, because different causes need different treatments, and some do not whiten at all.
Tooth color changes for many reasons. Some you can control, some you cannot. Here they are, group by group.
External causes (extrinsic stains)
These are stains sitting on the tooth surface. They come from what you eat, drink, and do each day, and they are easier to prevent and remove than the internal group.
- Dark food and drink. Coffee, tea, colas, dark red drinks, and strongly colored foods such as soy sauce and tomato sauce. If you drink coffee daily, the stain builds up and sets harder over time unless you have a scaling and polish now and then.
- Smoking. The most obvious culprit. Nicotine and tar collect on the tooth surface and along the gum line, dulling the teeth and often leaving dark brown deposits.
- Poor oral hygiene. Brushing that misses areas, or skipping floss, lets plaque harden into tartar, which is yellow to brown and makes teeth look darker than they really are.
Internal causes (intrinsic stains)
This color sits inside the tooth itself. You cannot brush or polish it off. Some causes can be prevented; others need dental treatment.
- Aging. The outer enamel thins with use, so the yellower dentin underneath shows through more. Teeth naturally look darker as we get older.
- Certain medicines in childhood. Antibiotics in the tetracycline family, taken while the teeth were still forming, can leave gray or brown bands in the teeth that are hard to lighten.
- A dead tooth (non-vital tooth). A tooth that took a hard knock, or has had root canal treatment, can slowly turn gray or dark from the inside. It usually stands out as a single tooth darker than its neighbors.
- Too much fluoride in childhood. This can leave chalky white spots or streaks on the enamel. It is a matter of uneven color rather than yellowing.
Which stains whiten, and which need another approach
- Surface stains respond best. Many people look noticeably brighter after a scaling and polish alone. If you want to go lighter still, whitening is the next step.
- Age-related darkening improves with whitening for most people, but the result varies from person to person. We assess first and tell you what to expect.
- Color from medicines or a dead tooth may lighten a little with whitening, but often unevenly. For a front tooth that shows when you smile, we sometimes suggest a veneer or a crown to cover the color instead, which gives a more even result.
- Existing fillings, crowns, and veneers do not change color with whitening. If you whiten the natural teeth around them, they will look darker by comparison, so we plan to replace them to match the new shade.
To know which group your teeth fall into, we need to look in your mouth. Often it is a mix of both, which is why we suggest an examination before choosing a method.
How to keep your teeth white for longer
If you want a bright smile that lasts, these simple habits help.
- Cut down on tea, coffee, and dark drinks, or use a straw so they touch the front teeth less, and rinse with water afterwards.
- Stop smoking. It darkens teeth faster than anything else and harms the gums directly.
- Brush properly twice a day and floss daily so plaque never gets the chance to harden into tartar.
- Have regular cleanings and check-ups. Surface stain is polished off before it sets.
- If your teeth start to look dull, do not rush to buy a whitening product. Come in first so we can find the cause, then decide between in-office whitening, a home kit, or something else.
Tooth discoloration happens to everyone. If it is affecting your confidence, talk to us before you decide. Prices for whitening and other treatments are on the price list.
Book a consultation
Not sure why your teeth look dull, or whether whitening will work for you? Come in for a check. We look at whether the color comes from outside or inside the tooth, and recommend what genuinely suits your teeth, not the most expensive option.
- LINE
- Phone: 098 831 0246
- Open daily 10:00–20:00 (closed Tuesdays)
- Tooth Boutique Dental Clinic, Venice Di Iris, Vacharapol Road, Bang Khen, Bangkok. Parking available.