Why are teeth white/yellow?
86047
Because enamel is translucent and it's the dentin (which is a darker shade than enamel) that is showing through.  Also, you will notice that your teeth get darker in colour the farther back in the mouth they are.  This is because they are not subjected to as much light as the front teeth are.  No one has truly "white" teeth.  There are people that want dentures made with teeth that are extremely white and you can also tell they are false teeth simply because teeth are just not naturally a true white.
564667
are you aware that your teeth can only get but so white. If your teeth are white already why waste $30- 40 on white strips. I found that  Colgate luminous and Colgate plus whiting advance(gel)works great and I live by them \n\nI use the Colgate plus whiting advance(gel)at night b4 bed and Colgate luminous in the morning .. And my smile always get its compliments... ;-D
952471
Well, you may be overdoing  it but i was the same way because i like to have a clean feeling mouth! However, you can actually brush away the enamal on your teeth and cause serious damage to the intergrity of your teeth. I did this and luckily my dentist caught it before it was too bad.  He noticed alternating "bands" of color (IE:my teeth were very white but i had places where you could see other shades and it was because i was brushing too much, in effect killing/ decaying the teeth). I try to brush as much as possible but within the limitations my dentist  set forth. Also, dont brush really hard adn if you continue to brush as often as you do use a softer toothbrush.
432014
during age, dentine (tooth structure under the enamel) not getting more yellow. it is still in the same color (light yellow). Enamel actually not totally white, but its also translucent. During age and wearing process, enamel will get thinner, and because its translucency, teeth will looks like more yellow.
1023778
Hey I got mine off about 5 months ago.  I just brushed three times a day.  This classmate had hers off about 1 1/2year ago and she had yellow teeth and a white squarish spots in the middle of each tooth.  I didn't want that for myself, It looked bad and nasty.  Like she didn't brush her teeth,  but it helped my teeth were good when i got them off.
1011173
Dental sealants are applied to the molars in one's mouth to prevent cavities. It is white so that it stays consistent with tooth color and it is a painless process.
1003477
The only way to get your teeth super white is by bleaching or veneers. Whitestrips do not wear tooth enamel away. I'm a licenced dental hygienist and I use them all of the time. They do cause sensitivity though but it goes away. That is the cheapest route. The next step up is bleaching trays and in office whitening which is expensive and not worth the cost for the instant gratification. Whatever you do do not go crazy with whitening toothpaste.  This really does wear down enamel over time, esp. if you are scrubbing because you don't like the tooth color. All that makes toothpaste"whitening" is just abrasive stuff. Then you scrub off the enamel to expose the dentin which is naturally yellow in color. Sorry to ramble but I see this every day.
930142
hydrogen peroxide is a reducing agent ie it removes oxygen from compounds when teeth are exposed to food particles that get stuck they form a film of yellow matter that cannot be removed hydrogen peroxide bleaches ie reduces the yellow matter it also kills bacteria by the same way by suffocation but too much of a good thing is bad and hydrogen peroxide with its mild acidic effect erodes the teeth over time
100989
a healthier teeth is not really white.. its light yellow and more yellowish near the gum.. the tip of the teeth may be whiter.. brush ur teeth daily twice, in the morning and bfore going to sleep.. wash ur mouth after having anything except water.. these can be done for a healthy teeth..
631573
yes it turns them yellow an ddoes many other things in ur gums wwhich are not visible and there are no signs of them...if u r worried about ur teeth just DONT smoke...ANYTHING!
804228
TOOTH DISCOLORATIONS\nWhat Is It? \nYour teeth can become discolored by stains on the surface or by changes in the tooth material. Dentists divide discoloration into three main categories: \n-Extrinsic discoloration — This occurs when the outer layer of the tooth (the enamel) is stained by coffee, wine, cola or other drinks or foods. Smoking also causes extrinsic stains. \n-Intrinsic discoloration — This is when the inner structure of the tooth (the dentin) darkens or gets a yellow tint. Causes include excessive exposure to fluoride during early childhood, the maternal use of tetracycline antibiotics during the second half of pregnancy and the use of tetracycline antibiotics in children 8 years old or younger. \n-Age-related discoloration — This is a combination of extrinsic and intrinsic factors. In addition to stains caused by foods or smoking, the dentin naturally yellows over time. The enamel that covers the teeth gets thinner with age, which allows the dentin to show through. Chips or other injuries to a tooth can also cause discoloration, especially when the pulp has been damaged. \nIn rare cases, children with a condition called dentinogenesis imperfecta are born with gray, amber or purple discolorations.\n\nSymptoms \nSymptoms include stains on the enamel or a yellow tint in the dentin. \n\nDiagnosis \nNo special tests are needed. A dentist can diagnose tooth discoloration by looking at the teeth.\n\nExpected Duration \nSome tooth discoloration can be removed with professional cleaning, but many stains are permanent unless the teeth are treated (whitened) with a bleaching gel.\n\nPrevention \n-Brushing your teeth after every meal will help to prevent some stains. Dentists recommend that you rinse your mouth with water after having wine, coffee or other drinks or foods that can stain your teeth. Regular cleanings by a dental hygienist also will help to prevent surface stains. \n-Intrinsic stains that are caused by damage to a nerve or blood vessel in the inner part (the pulp) of a tooth sometimes can be prevented by having root canal treatment, which removes organic material before it has a chance to decay and darken. However, teeth that undergo root canal treatment may darken anyway. To prevent intrinsic stains in children, avoid water that contains a high fluoride concentration. You can check the concentration of fluoride in your drinking water supply by calling the public health department. Then consult your dentist.\n\nTreatment \nDiscoloration often can be removed by applying a bleaching agent to the enamel of the teeth. With a technique called "power bleaching," the dentist applies a light-activated bleaching gel that causes the teeth to get significantly whiter in about 30 to 45 minutes. Several follow-up treatments may be needed. \nIt's also possible to remove discoloration with an at-home bleaching gel and a mouth guard given to you by your dentist. The bleaching gels designed for use at home aren't as strong as those applied by your dentist, so the process takes longer — usually two to four weeks. Whitening toothpastes may remove minor stains, but they aren't very effective in most cases.\nIf you've had a root canal and the tooth has darkened, your dentist may apply a bleaching material to the inside of the tooth. When a tooth has been chipped or badly damaged or when stains don't respond to bleaching, your dentist may recommend covering the discolored areas. This can be done with a composite bonding material that's color-matched to the surrounding tooth. Another option is to get veneers, which are thin shells of ceramic that cover the outer surfaces of the teeth.\n\nWhen To Call a Professional \nTooth discoloration is mainly a cosmetic problem. Call a dentist if you're unhappy with the appearance of your teeth. Any change in a child's normal tooth color should be evaluated by a dentist.\n\nPrognosis \nThe prognosis is very good for extrinsic stains. Intrinsic
896556
Before I answer your question I just want to state that I am a Dental Technologist not a Dentist. Dental Technologists only make dental prosthesis with a prescription from a Dentist and we do not give out medical advice.  Thus, any comments I make are just personal thoughts and should not be taken as medical advice. So GO TO YOUR DENTIST!!!!!\n\nNow to answer your question, with age your Enamel layer wears down exposing more of your Dentin layer which gives the yellowish color. Yellowing of teeth is natural but if you want to do something you can bleach. Bleaching bleaches the dentin layer but it’s not the healthiest thing to do to your teeth.\n\nI hope this helps
876550
the are not white spots, its the only bit of white teeth that you have left
633630
if your son hasn't been  in the habit of good oral hygiene and just started then they are yellow from stains of plaque.  Getting him into a good regime is the answer.  If he drinks alot of cokes, tea and red colored food then these are from the dyes in the food.  He should brush after each meal to help eliminate the reside from residing on his teeth.  Good oral hygiene is the key to longevity of teeth.  Brushing after every meal and before you go to bed and flossing one a day.
463465
At first I used them as directed for a week and it worked really well. People commented that my teeth looked whiter (they weren't horribly yellow to begin with) Now I use them once or twice a week at night for 30 minutes to keep them as white.
407308
Get your teeth bleached.
344118
I work for a dentist the best thing to do is just keep your teeth brushed good. If you use any thing to make them white you will have two diffrent shades when you have the braces removed.