May The Force Be With You

As dentists, we work with our hands everyday to fix things in the mouth.  The two most common diseases that can destroy the mouth are dental caries and the periodontal disease.  However, I think we don’t spend enough time understanding the forces in the mouth.  These forces can be occlusal forces, parafunctional forces or even habits the patients have developed.

I don’t remember too many things during literature review in my residency.  But I remember one article that really got my attention.  And to this day I still think about this article every now and then.  It allowed me to identify red flag patients that have high occlusal forces.  These patients probably have destroyed  a lot of the dentistry in the past.  And they probably will destroy my dentistry even if I offer my best efforts.  I have learned that I can’t fight nature but it is important that you recognize these patients so you can manage their expectations from the get go and treatment plan accordingly.

This article was written in the 70s by Dr. Girard DiPietro[i] and it talked about how the Frankfort mandibular plane angle as a way to relate the type of occlusal forces and the prosthetic challenges one can anticipate.  Low Frankfort mandibular angle often means the biting forces are high.  The elevator muscles are in vertical alignment with the molars and can produce very high destructive force.

Another clinical features to watch out for include a brachycephalic head shape, an everted lip and a prominent chin.  Together, along with a low Frankfurt mandibular plane angle, these patients can produce very high occlusal forces.  So my treatment plan strategies may include some of the following features:

1/Manage the patient’s expectation

2/Discuss future options of remakes

3/Maximum support for the prosthesis. Avoid cantilever or long span bridges.

4/Consider splinting so the forces can be more evenly distributed

I hope you will recognize these patients in your practice and that the force will always be in your favour.  Thanks for reading!

[i] DiPietro, G. (1977). A study of occlusion as related to the Frankfort-mandibular plane angle. The Journal of Prosthetic Dentistry, 38(4), 452–458.