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Hello. When was your Bells Palsy? That's primarily a problem with the muscles of the face..did you have numbness with it? As for the numbness in the other lip, is it only the upper lip? Does the numbness involve the entire upper lip? What about the gums on that side, or the face?
I first got the Bell's exactly one year ago. It gradually improved over about 3-4 months, then stopped improving. Shortly thereafter, synkinesis set in, and along with it, numbness on my upper lip on the left side. The Bells was on the right side. I've had an MRI which didn't reveal anything.
As you probably know, Bell's is a disorder of the facial nerve (cranial nerve VII). Sensation of the face (incl the lips) is supplied by the trigeminal nerve (cranial nerve V). There is one on each side, and while they generally "respect the midline", some small branches can cross over. If the entire upper lip is numb it is not likely to be cross over from the contralateral trigeminal nerve. The issue would be with the ipsilateral superior labial branch of CN V.
How long has the numbness been present? Does it feel numb all the time or only to touch?
It feels numb all the time time, and the numbness wasn't there at the onset of the Bell's. In the beginning, there was only numbness on the left side, the Bell
s side, and that numbness is still present. The numbness on the opposite side only set in later, as the synkinesis developed. At least, that's how it seemed to me.
Does the synkinesis involve the left side at all?
no. only thing on the left side is the upper lip numbness
Because these events are occurring on opposite sides of the face, it is a bit difficult to put them together in a neat package, unless you had a chronic neurological conditon like MS, or another demyelinating disorder affecting primarily your cranial nerves. Since your MRI is normal, the only other test to look for something like this would be lumbar puncture (spinal tap). You could ask your doctors about this.
You might also ask about being screened for a rheumatologic condition (e.g. a vasculitis), though this would be even less likely in my opinion. Otherwise, the left lip numbness could be due to a local problem somewhere along the path of the left CN V, such as a sinus infection, or dental problem. You should probably discuss this with a dentist as well just to be sure you are not missing a dental source.
What is a demyelinating disorder?
In some disorders, the body's immune system attacks the protective sheath around the nerves (like the insulation around a wire). This can cause the nerve to transmit signals more slowly or to send out bogus signals to the brain (suggesting numbness or burning, for example, in the skin even when nothing is actually there to cause it). The protective sheath is called myelin, and when it is damaged (demyelinated), the affected nerves become dysfunctional.
is there a remedy?
For most demyelinating diseases there is no cure. They can progress very slowly or rapidly or intermittently. Treatment focuses on strategies to treat attacks and modify the course of the disease. But you should not worry about having something like this unless your doctors were to uncover more evidence of it. Based solely on your symptoms above, it is still unlikely that you have something like this.