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How to make a differential diagnosis using a Lucia Jig

I want to spend a few minutes today discussing the benefits of utilizing a Lucia Jig to make a differential diagnosis. All right. Here's what I mean by that. Many times, you're going to have patients that come in the door, and they're going to be complaining about TMJ pain.


Internal derangement of TMJ or occlusal muscular problem?

Now, we can have a problem where a patient is having pain because of internal derangement of the temporomandibular joint. But, really, most of the time, most of the patients are going to be coming in and are going to be having occlusal muscular problems, specifically with the lateral pterygoid. If you have a very sore and inflamed lateral pterygoid muscle, that muscle goes back and attaches to the capsule itself over top of the head of the condyle, which contains the disc. So if you have a very sore, spasming lateral pterygoid muscle, those patients may also complain about discomfort or even pain, and it could be muscular of nature.

Using the Lucia Jig to decide.

So the question becomes, when our patients come in the door, how do we differentiate between the two? That's where the Lucia Jig comes in. If you put a Lucia Jig into this patient, the Lucia Jig is going to separate the posterior dentition. What that does is it deprograms the muscles of mastication because the back teeth are no longer touching. Now, when the back teeth aren't touching and the lateral pterygoid muscle relaxes. If you're dealing with an internal derangement problem, putting the Lucia Jig in is going to make the patient get worse, and they'll usually get worse very quickly. If the patient is dealing with an occlusal muscular problem and you place them in the Lucia Jig, usually within about 5 to 10 minutes, they're going to have complete resolution or a decrease in the symptoms that they were presenting with. This is going to lead you more towards an occlusal muscular problem.

So Lucia Jigs can be a wonderful tool to have in your office to help you to make a differential diagnosis between occlusal muscular issues or internal derangement issues. Make sure that you use it wisely, and if the patient is having an increase in their symptoms, be sure to take it out right away and move forward with treating the joint.

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Picture of Dr. Leonard Hess

Leonard A. Hess, DDS is the Clinical Director at The Dawson Academy and joined the faculty in 2009. He owns Union County Center for Comprehensive Dentistry in Charlotte, North Carolina, and practices full time in addition to teaching continuing education courses. He is a member of the editorial board for Inside Dentistry and has had over 17 articles published in peer-reviewed journals. He is also a member of the American Academy of Restorative Dentistry, AACD, ADA, AES, and NCDS. Dr. Hess began teaching continuing education courses in 2005 on topics including occlusion, smile design, treatment planning, preparation design, and practice integration of Complete Care Dentistry. He’s taught full-day continuing education courses at the American Academy of Cosmetic Dentistry’s national meeting, The Greater New York Dental Meeting, AACD National Meeting, Pacific Dental Conference, Ontario Dental Association meeting, and The Yankee Dental Conference. Dr. Hess has taught courses in Japan, Germany, Poland, China, and Canada.