Wisdom Teeth (Third Molars)

Human beings have more teeth than they actually need: four more teeth, to be exact. The third molars (wisdom teeth) are the last teeth on each side and in each arch of the mouth. If we don’t need them, why do we have them? Hundreds of thousands of years ago, our ancestors didn’t look a great deal like we do today. They had smaller bodies but larger and more powerful jaws. Their diet dictated this jaw structure and number of teeth. Our ancestors ate tougher and more abrasive types of food. It wasn’t cooked well, and it wasn’t ground up well. There were a lot of hard grains and foods that required lots of chewing. Big jaws were capable of holding more teeth for this chewing.

Today, we don’t need the heavy grinding capacity that early humans had. Food is easier to eat, less abrasive, and much softer. Evolution is reacting (slowly) to this fact by decreasing the size of our jaw bones and chewing muscles. The human jaw that once comfortably held 12 molars (32 teeth total) is now often only large enough to hold eight molars (28 teeth total). Unfortunately, our jaws are getting smaller faster than our wisdom teeth are disappearing. The wisdom teeth often do not have enough room to grow properly. Eventually, thousands of years from now, humans will not have wisdom teeth. They have lost their function and are gradually disappearing, just like the appendix.

Since the jaw is too small (for most people) to accommodate the third molars, they come into the mouth partially, poorly positioned, or not at all. They can be fully erupted, partially erupted, a soft tissue impaction, partial bony impaction, or full bony impaction. If teeth come in well and you are able to keep them clean, we leave them alone. If they are crowded or poorly positioned and cannot be kept clean, they are like an accident waiting to happen. Decay and gum infection are likely to result. These teeth are usually removed—ideally before they begin to cause big problems with the second molars that are directly ahead of them. Teeth that are partially erupted should always be removed: there is too much opportunity for gum infection to begin. If the teeth cannot be cleaned, chronic painful inflammation may occur (pericoronitis). The earlier they are removed, the better your healing will be.

Less complex extractions (fully erupted teeth or partial soft tissue impactions) can be done by a general dentist. We will refer difficult extractions to an oral surgeon for treatment. Depending on the type of extraction and the medical history of the patient, the extractions may be done in an office or in the hospital. This will be determined after viewing radiographs of the teeth. Having all four wisdom teeth out at the same time is a common practice. Postoperative discomfort can be minimal to extreme—in the case of difficult full bony impactions. Antiinflammatory and pain relief medications are prescribed appropriately.

We do not need wisdom teeth to eat well. If they need to come out, it is better they come out (1) before they cause problems with the adjacent teeth that you really need and (2) when you are younger and heal well. If you need to have one wisdom tooth taken out, also have the opposing wisdom teeth removed. When a tooth does not meet an opposing tooth, it “super erupts” or continues to grow out of the normal position. When left for some time, the remaining tooth can develop decay and gum disease and cause the same thing to happen to the tooth in front of it.