My child has black spots on their teeth.  What is this and what should I do?

Unfortunately,  black spots on teeth are usually the sign of a problem.  The most common cause of black spots on both baby and permanent teeth are cavities. In the early stage of cavity development, they appear white or yellowish and are “chalky” looking.  This description is given so because the consistency of the cavity is such that it feels like chalk if you were to touch it.  It literally will “flake” away if touched with a dental instrument.  If the cavity continues to progress, it will go through several other color and consistency changes which typically yield an end-result of the black color.  Sometimes they may only appear dark brown, as color can vary between individuals.

There may or may not be any pain at all associated with the cavity.  Frequently when I find cavities the first thing that people will say to me is, “But Doc, it doesn’t hurt.”  My next response is almost always, “Cancer doesn’t usually hurt either-until it has progressed too far.”  Tough analogy, I know but very true.  If a cavity gets to the point where it hurts or starts that “twinging” feeling, it usually means that it is pretty large already.  This may or may not mean that the tooth needs a root canal.  But first, let’s describe the cavity process and how it effects teeth.

A cavity is simply a bacterial  infection in the tooth.  These bacteria use the sugar in our foods to “eat” and thrive.  As they “digest” these sugars, the bacteria secrete a strong acid as a waste product.  This strong acid decomposes healthy tooth structure (called enamel and dentin, which are non-living substances) and turns it soft and mushy.  If this process continues, it eventually decomposes close to or into the nerve chamber of the tooth (also called the pulp chamber or nerve).

Once these bacteria are exposed to the living tooth nerve tissue, it infects the pulp chamber and causes the nerve and blood vessels in the tooth to die.  The process is usually quite painful in its final dramatic death scene, but may eventually stop hurting.  Loss of pain sensation is because the infection likely found a way to escape the highly dense tooth compartment (the tooth root system and surrounding bone).

Here’s where it gets really gross.  This release of pressure and pain is because the pus/infection found a way to drain into the mouth.  Often you can’t see where it is draining, but sometimes you can.  It is usually in the form of a little “knot”  or bump on the gum next to the tooth which expels puss through a tiny little opening.   This secretion of puss releases pressure build up from the infection and then suddenly you feel much better.  At least for awhile.  If left long, the infection will come back much worse, usually with outward and swelling and a whole lot of pain!

Once this start of this entire process begins, it is irreversible and the dead nerve tissue has to be removed or a massive infection can occur.  This infection can stay localized within the jaw, but can also become life-threatening if the infection enters the blood stream and goes through the rest of the body.  This process to remove the infection is called a root canal and the treatment and type of root canal depends on whether the tooth is a baby tooth or a permanent tooth.  We’ll address root canals of both kinds in a later section.

Trust me when I tell you that root canals have gotten a bad reputation.  Yes they are expensive (can range from $600-$1000 each), so preventing them is better than having to pay for one.  However, the reputation they have received for being horribly painful is a myth.  Normally root canals are only painful if you wait to go to the dentist until your infection/abscess is very bad (swollen and/or painful to the point of tears).  The reason for this is that the localized infection actually counteracts the anesthetic used to put the tooth to sleep, allowing the root canal procedure to be felt.  Very painful indeed.

So what exactly is a root canal?  Well, simply put, a root canal is the removal of the dead or dying nerve tissue within the tooth, followed by a cleansing of the nerve canals to remove as much of the bacteria as possible.  Then the empty, clean nerve canals are filled with a special sterile rubber material which seals the canals to prevent more bacteria from entering the tooth.  It is generally not painful at all, and one of the dental procedures I consider to be the most boring and relaxing of all (for both the patient and the dentist).  The key here again is to NOT wait until it starts to hurt.  If you or your child feels something strange going on in a tooth, it is always better to have it looked at and be on the “safe-side.”

While the black spots are usually cavities, this whole root canal process is meant to describe what happens in a permanent tooth.  Baby teeth can also get these same types of cavities, but the treatment is slightly different for both the cavity and the root canal (if needed).  The discussion on treatment of cavities and root canals in baby teeth will be discussed further in the next few questions.

There are other causes for black spots, but they are less common and include the following: damage during tooth development, underlying systemic disorders and excessive amounts of fluoride (usually occurs when given excessive fluoride supplement).  As always, take your child to the dentist for an evaluation immediately if you see black or white spots on their teeth.

Tags: Analogy, Bacteria, Bacterial Infection, Black Spots On Teeth, Blood Vessels, Cavities, Cavity, Chalk, Consistency, Dental Instrument, Dentin, End Result, Flake, Nerve Chamber, Nerve Tissue, Permanent Teeth, Pulp Chamber, Root Canal, Sugars, Tooth Structure