We consider a variety of facial features when we approach an orthodontic case, including your overall facial shape, gums, lips, cheeks and chin.
All of these facial features serve unique purposes. That is, all of them but your chin. The chin isn’t alone. Our bodies have evolved over thousands of years, and there are body parts that don’t serve any good purpose for us these days. Take the appendix and the wisdom teeth, for example. These can be removed and it won’t alter your life quality a bit.
But here’s the difference between those superfluous parts and the chin: while scientists understand that the appendix and wisdom teeth once served useful functions, they can’t say the same for the chin.
A recent TIME magazine article shares how Nathan Holton, a post-doctoral researcher who specializes in craniofacial structure in the University of Iowa Department of Orthodontics, chose 37 subjects whose facial measurements were taken regularly from age 3 to young adulthood, during their participation in the Iowa Facial Growth Study.
It was believed that forces exerted by the jaws helped dictate jaw size. The belief was the greater the force, the greater the bone mass in the chin. However, the research failed to prove that.
Now Holton and University of Iowa anthropologist Robert Franciscus, a collaborator on the study, “suspect that the face shrank away from behind the chin as primitive and pre-humans became modern humans, making it appear larger relative to everything else. The reason, as with so many things in the human species, has to do with male behavior—specifically violent male behavior,” according to the TIME article.
Franciscus believes that as people migrated to other parts of the world from Africa and formed societies, males had to become more cooperative, rather than competitive. That meant males had to tolerate each other and act less aggressively. And so the chin began to evolve as a noticeable feature.
We’re sure it was quite a while later that we started truly noticing chins and assigning adjectives to describe them – weak, strong, chiseled, dimpled – but now that they are, you can bet our image-driven society puts a lot of effort into making sure they look good. And even though the chin may serve nothing more than an aesthetic function today, it remains a notable facial feature. Who would Jay Leno be without his chin? His chin is so well known, it has its own Facebook page.
Chins and Orthodontic Treatment
Now that we’ve established that most of us want our chins to look good, let’s explain how we achieve changes to this part of our face through orthodontic treatment.
Chin position and appearance often is the chief complaint for patients whose upper teeth appear to jut out too far. This can be because of an underdeveloped chin, or the upper teeth could just give the chin a recessed appearance. Another common chin-related complaint is when the lower teeth jut forward beyond the upper teeth to create an underbite. This forces the chin outward and can create a concave profile where the cheeks also appear sunken. These types of malocclusions are referred to as Class II and Class III, respectively.
The chin plays an important role in orthodontic treatment of these cases, because we want to make sure it is proportionate to the rest of the facial features. Through treatment, we can guide jaw growth to create a more favorable relationship among the facial features and a more pleasing profile.
Addressing Class II and Class III malocclusion is most successful and frequently least invasive when the problem is diagnosed and treated during childhood. This is one reason why orthodontists recommend that every child receive an orthodontic evaluation by age 7. Class II and Class III malocclusion can be diagnosed at this young age, and I can incorporate your child’s growth into the treatment plan.
Using Appliances to Treat Class II Malocclusion & Improve Chin Appearance
The Herbst appliance is a highly effective tool in treating Class II malocclusion because it advances the lower jaw and decreases the distance in which the upper front teeth sit forward of the lower front teeth. This also creates a more pronounced chin.
In some cases I may equip a Herbst appliance with additional appliances, such as expansion screws, to widen the dental arches if necessary.
A headgear activator also is a common appliance used to address overjet that works similarly to a Herbst appliance.
A twin block appliance is another tool that promotes lower jaw growth. The appliance consists of upper and lower plates and is commonly used in children who are still growing. It is equipped with a screw that must be turned weekly to help position the jaw forward. It may be used as an initial phase of treatment before your child gets braces.
You can learn more about how I treat Class II malocclusion in this article titled, “What Options do I Have to Fix My Overbite?”
Using Appliances to Treat Class III Malocclusion
The maxillary expander tends to be our go-to corrective appliance when it is determined that lower jaw growth is outpacing the upper jaw. We fit an expander in the roof of the mouth and you or your child adjust it daily with the turn of a key. Once the appropriate width is achieved, the appliance is no longer adjusted, but left in place for at least three months to stabilize the palate.
Reverse-pull headgear, also called a facemask, is an appliance we can use to promote upper jaw growth by coercing it forward. We us elastic bands to connect the vertical frame to braces or molar bands worn on the upper molars to exert the pulling force that encourages the upper jaw to catch up with the lower jaw.
If we need to suppress lower jaw growth, I may recommend a chin cap.
We explain treatment for Class III malocclusion in greater detail in our article titled, “What is an Underbite?”
Orthodontic treatment with braces usually follows interceptive treatment for Class II and Class III malocclusion.
Has your child received a complete orthodontic evaluation yet? If not, please call our office for an appointment so we can determine if conditions exist that would benefit from interceptive treatment.