>> I am looking for a rubric which describes the phenomenon of not being
I personally had great results using Mag Phos after having the jaw stiffen up 
and refuse to close after a prolonged visit. I had all of my mercury fillings 
removed within 48 hours in the 80's before the safe protocols were known. No 
rubber dam or anything to keep the flying mercury from getting swallowed or 
mask to keep me from breathing the fumes. I got really sick and had to do a 
detox. (another story)
However I could not close my mouth for several days until I took Mag Phos 30c 
for several doses.
Something else that I did was to put a warm compress on my face and used my 
finger to massage the area on the inside and outside. At first I tried to just 
keep forcing the jaw closed but that produced more spasms. I also placed my 
fingers at the TMJ articulation by the ear and found the left side was jutted 
laterally and the right side had a small indent. This led me to believe my jaw 
was really out of alignment or with an incomplete dislocation. I used a tapping 
thrust to push my jaw to the right followed by more heat and more massage and 
more thrusting. It worked after about a day. Later my Chiropractor said he 
could have used an activator to put it back into place for me.  Later I used 
Ruta to help heal the tendons and ligaments. Arnica did help to reduce some of 
the swelling that was contributing the locking to begin with.
Primary things to look for in your case IMHO are
How much if any swelling is there and where is it located?
Is the swelling from muscle tissue strain or bleeding into the joint?
Is there any cramping of spasms?
Can you feel a variance when pressing on the TMJ joint where the zygomatic 
process and the articulation of the mandible come together near the ear? If so 
consider it a subluxation or dislocation and treat accordingly.
Has a nerve been damaged which would have usually sharp pain tingling, 
numbness or shooting pains along the nerve pathway (hyp)
what modalities make it better? Hot, cold, warmth, cool, pressure, no 
pressure, daytime, nighttime, etc?
A couple of years ago I found Dr Luc's site giving a lot of remedies for 
dental issues. He also lists cuprum for cramping if that type of spasm is keeping 
the jaw open.
http://www.drluc.com/dentist.html
TEMPOROMANDIBULAR JOINT (TMJ) 
Arum triphyllum - Use for pain in joint on swallowing. 
Calcarea flourica - Use for hypermobile joints 
Calcarea phosphorica - Use when mouth cannot be opened withoutpain. 
Carbo vegetabilis - Use for vertigo with nausea and tinnitus. 
Chamomilla - Use for low pain threshold. Unbearable spasms ofpain radiating 
into the ear. 
Cuprum metallicum - Use for trismus of muscles. 
Granatum - Use for painful cracking of the joint. 
Mangesium phosphorica - Use for muscle spasms. 
Phyltolacca decanda - Use for earaches with pain extendinginto teeth, jaw, 
and throat. 
Rhus toxicodendron - Use for joint stiffness that improveswith movement and 
for popping" of TMJ. 
Magnesia phosphorica: -Use for stiff, sore jaws following prolonged dental 
work when the muscles are cramped and feel better with warmth. 
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