Third molars challenge conventional ‘wisdom’

Everyone knows someone who has endured a few days with a swollen face after removal of their third molar teeth (known as ‘wisdom teeth’), or had to live through pain and infection from a wisdom tooth that should have been removed but wasn’t.  With that in mind, it is easy to understand why third molars have developed a nasty reputation.  Does this imply that all wisdom teeth are bad, or should be removed on a ‘preventive’ basis?  The short answer: definitely not.

Before delving further into this subject, it is important to understand a little about the history of wisdom teeth and why they are often problematic.  At the risk of digressing to the argument of Darwinism versus Creationism, it is reasonable to state that most health care professionals are on the side of evolution, or natural selection.  Evolution certainly allows for an easier explanation of the wisdom tooth predicament.  Prior to the agricultural revolution and the milling of grains, our ancestors had a much more coarse and fibrous diet, requiring much greater chewing demands.  Hence, our ancestors had a much larger jaw.  A more refined and softer diet has ostensibly led to a decrease in jaw size.  Unfortunately, the teeth have lagged behind, and now it is common for people to have more teeth than they have room for in their jaw.

This explains the prevalence of both third molar crowding (since they are the last teeth to grow into the mouth) and generalized crowding and orthodontic problems.  Evolution is catching up – current statistics indicate that up to 25% of the population is missing at least one of their wisdom teeth, and some very fortunate individuals are missing all four.  The good news, if you are an evolutionist, is that in 10,000 years no one will have wisdom teeth.   The present reality is that wisdom teeth have been unfairly labeled as being ‘all bad’.  Just as there is human variation in height and body frame, there is similarly a wide variation in both jaw size and tooth size.  Simplistically, some people have room to accommodate their wisdom teeth and others do not.  Wisdom teeth are extremely variable in their position, some growing straight, and others angled unfavourably due to crowding and other factors.

Since wisdom teeth typically grow into the mouth between the ages of 17 and 25 years, it is very important that teens and young adults in this age range have regular dental examinations, including x-rays of the wisdom teeth. While it is true that not all wisdom teeth are bad, it is similarly true that absence of pain does not necessarily mean there is no problem.  It is all too common for undiagnosed wisdom tooth problems to jeopardize the second molar teeth immediately in front of the wisdom teeth.

The discussion of wisdom teeth begs an important question – if research and technology have come so far in the last 100 years to prevent common dental problems, why haven’t we advanced dental science to prevent wisdom tooth problems?  Fortunately, this may be changing.  Current research is studying whether or not it is cost effective, safe and viable to prevent these teeth from forming in the first place.  Known as intentional therapeutic agenesis, it would involve a minimally invasive procedure carried out on young children under the age of five, analogous to vaccinating young children for infectious disease prevention.  Future research will undoubtedly focus on genetic engineering to inhibit the formation of third molars.  When you consider that two billion dollars a year is spent in the US (sorry, we don’t record such statistics in Canada) on removal of wisdom teeth, not including examinations, consultations, x-rays, anesthesia, post-op visits and time lost from work, perhaps it is research worth pursuing.

Dr. Allan Katchky is a dentist who practises in the East End

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