Do I need jaw surgery fix my gummy smile?

Never look a gift horse in the mouth, so the old saying goes. It was believed that a horse's deteriorates as it ages and hence looking at a gift horse in the mouth is considered a rude gesture. I guess the same can be applied to humans. What is striking though about a horse's mouth, is that it is very gummy. Hence every time I see a patient with a gummy smile, I am reminded of a horse. Not a flattering thought but somehow, it sticks. Fortunately, there are many solutions to fix this problem. Most people usually adapt by not smiling too widely, or covering their mouth, or tipping their heads downwards, especially when they are asked to smile for a photo. Such behaviour modification is instinctive. However, there are treatments that reduces or even eliminate gummy smiles completely. This range from a simple botox injection to corrective jaw surgery.

The choice of treatment depends on the cause of the problem. A thorough examination is needed to arrive at the correct diagnosis so that the appropriate treatment can be given. What are the possible causes of a gummy smile.

1: Short upper lip

Some people have a short upper lip that exposes more of the upper front teeth even when not smiling. For this group of people, smiling immediately expose the entire row of teeth and the gum above them. However, there is no predictable method of lengthening the lip. Some surgeons may attempt lip lengthening surgery but the results are equivocal at best. The lip is a unique part of face that is made up of skin, muscle, and two types of mucosa, the drier, darker red mucosa that gradually merges into the wet pink mucosa that faces the teeth. Any surgery of the lip that alters the proportion of the different tissue types will alter the overall aesthetic appeal. Hence, I usually do not recommend lip lengthening procedures as a routine treatment for the short upper lip, even though it is the cause. Because it is never a single factor in isolation that causes the gummy to show, I look for other contributing factors and see what can be done to eliminate them to improve the overall appearance.

2: Overactive muscles

A smile requires muscular contraction. There are several muscles that are responsible for smiling and some of these muscles may be slightly overactive, resulting in excessive lifting of the lips and hence showing too much of the gums. This is where behaviour modification comes in. However, it is tiring to always have to restrain your smile. To reduce the gum exposure, these muscles can be injected with a neurotoxin like botox that blocks the muscle receptors, and hence preventing the muscles from contracting. A botox injection in the right spot will reduce the pull of the smiling muscles, and hence reduce the amount of gum showing. This is a temporary measure as the effects of the toxin will wear out over a period of 6-9 months. Repeat injections can be given by your dentists once or twice a year when you go for your routine six-monthly dental checkup. 

3: Undererupted teeth/thick gums

Sometimes, gummy smile is a simple problem of just having too much gum. In this kind of situation, the crowns of the teeth will appear smaller than usual. It will appear as if the teeth are not fully erupted into the mouth. A minor surgery to trim and contour the gum can be done under local anesthesia, using the good old scapel or something more sophisticated like radiofrequency or laser. The benefit of using radiofrequency or laser lies in its bloodlessness and the cutting electrode or probe coagulates as it cuts, enabling the surgeon to see clearly how much is cut and whether to cut more. As a general rule, it is best to cut less than expected as the gums do shrink after surgery. If there is still too much gum after healing, you can always cut some more but if too much has been cut, you can't put it back, at least not without a more complex procedure.

4: Excessive bone growth

The tooth-bearing part of the jaw is call the alveolar bone. When the alveolar bone of the upper jaw (maxilla) grows excessively, it carries the teeth and gum into a more forward and downward position than normal. This results in a condition called vertical maxillary excess (VME). It not only makes the smile gummy but makes the face look long as well, giving rise to the alternative term "long face syndrome". Jaw surgery is the only way to correct this. The resultant changes facial appearance then go beyond just correcting the gummy smile but to shorten the face and reduce the protrusion of the jaws and teeth. This is a very common feature in oriental faces but is often underdiagnosed. Many people with VME wrongly mistake this to be a orthodontic problem alone and seek orthodontic treatment to retract the front teeth backwards. Orthodontic treatment may reduce the amount of protrusion of the teeth but it cannot change the position of the jaw bones. The best solution in such cases is to have jaw surgery to reposition the upper jaw upwards and backwards, akin to tucking it under the upper lip, which remains unchanged. The operation will be a double jaw surgery as the lower jaw will also need surgery to match the new position of the upper jaw. For this condition, we can usually adopt a surgery first approach. Postoperatively, orthodontics is required to finetune the position and alignment of the teeth. This will typically take about 1.5 to 2 years.

5: Combination

In reality, most patient present with more than one cause of gummy smile. There is a combination of different factors and each of these need to be considered in order to come to an accurate diagnosis. While some treatment like botolinum toxin injection is non-invasive and reversible, others like surgery are not. So the correct diagnosis is of paramount importance. Spend time with your dentist or surgeon to understand what your causative factors are and get the right procedure done.