October 16, 2010

Joint Vibration Analysis (JVA)

If you have a big case, you’d better use the JVA pre-op.

Disclaimer:  I am certainly not an expert using the JVA.  This is the original software I got back in 2005 (and could use some software updates) when I was taking the Hornbrook Group Full Mouth Synergy course and have found it to be very useful.  Knowing the condition of the joints and having a tangible record of it BEFORE you endeavor into a large fixed case is in my opinion, priceless.

There are many different ways around the world to access the TMJ functions, but none can come close to the simplicity of the JVA.  Think of it as a Doppler that breaks down and analyze the frequencies of the sound coming from the joints.  Frequencies that are below 300 Hz and usually involved with soft tissue changes and above are hard tissue (bone/cartilage) changes. In our office we only do the “JVA Quick” to get 5 to 7 jaw openings and closings to establish an average joint sound.  I wish we had the jaw tracker that comes with this system, but haven’t got $12,000 bucks for it, yet!  Anyone of the recorded joint opening and closing sounds maybe at the extreme end of the frequency spectrum and may represent a paroxysmal event that you just lucky to catch so look out for those as well.

We use the JVA along with the TekScan to evaluate the pre-condition of the joints for large fixed cases and for symptomatic joint or muscle pain.  My assistants can set-up both the JVA/T-scan in just a few minutes and enter all the patient’s data into the patient list. The microphones are positioned over the TMJ’s bilaterally and I usually lead the patient through the opening and closing as I watch the metronome of the program that I have running just behind the patient’s head.  Once I get a full screen of fully open and closed bites (usually 5-7 cycles) I direct the assistant to push the “Accept” button.

Look at the above numbers and notice the that one set of columns are the average of the window to the right.  In this instance there are actually 6 windows but you would have to scroll over to see the others.  Follow the below algorithm to find the suggested diagnosis.  Remember this is just a suggestion and you will have to use all the data taken from teh examination of the patient to put together you final diagnosis.  For instance, we know that clicking and popping only comes from the left side so even though the algorithm for the right side would also lead to the suggested diagnosis of “Acute DD” (acute disk displacement), we considered the right to be normal.