The white spots are typically considered to be a “hypocalcification”, or a loss of mineral content on the surface of the teeth.
There are several factors that can cause white spots….dry mouth, acidic foods and drinks, acid reflux, plaque build-up from poor oral hygiene, and even celiac disease. (Patients involved in orthodontics (braces) often exhibit white spots from their hygiene not being good enough and plaque building up to a high level).
These white spots may be purely cosmetic, but often they indicate a weakening of the enamel, even to a point whereby decay is already beginning to grow under the white spot. The only real way to know is to see your dentist. Getting a regular fluoride treatment at the dentist’s office can go a long way to getting the tooth remineralized and preventing future spots.
If the white spots are superficial and there is no decay, a procedure called “micro-abrasion” can be utilized with much success. Basically, an abrasive polisher is used to “rub out” the white spot. Underneath would be normal tooth structure colored the same as the rest of your tooth.
If the spots are deemed to be deeper than just on the surface, the spot can be abraded away and the spot refilled with a small composite resin bonding that perfectly matches your tooth.
You might be asking about the white spots on a very young child. While some of the above reasons could still possibly apply, sometimes kids develop white spots for the complete opposite reason- they have a condition called “fluorosis” where there is, you guessed it, an excess of fluoride. While not as common anymore, there was a time when many people gave their kids flouride tablets to chew/swallow. That practice has fallen mostly out of favor and the problem has definitely diminished. However, there is a reason that kids have their own toothpastes; the fluoride content is lowered to a safe level. This is done mainly because kids aren’t always great at spitting all their excess toothpaste out, and instead they swallow it. (This is just one more good reason that parents should monitor their child’s brushing!) 🙂