Pain in TMJ HOME
Pain
is one of the most annoying and motivating factors for human being to look for
medical care.
It
is a human as well as a socio-economic issue, which give this subject more
interest on different aspects. A lot of literature was written about this
subject from different angles, and still there is a lot to be written and said
about this complicated subject.
What
is TMJ?
Temporomandibular
joint is the articulation of the lower jaw head (mandible) with the base of
skull bone (called temporal bone). Movement of this joint allows eating,
talking, and even laughing!
Painful
temporomandibular disorders (TMDs) are currently viewed as an umbrella term,
which constitutes mainly muscular and arthrogenous (articular) disorders.
Research diagnostic criteria (RDC) are now used to classify the symptoms and
signs of TMD. The epidemiology of TMD according to these RDC/TMD suggests that
around 10-12% of the population is afflicted with a strong female predominance.
Study
of pain:
Pain,
and specially, in TMJ happen in episodes, in different times, levels and
severities, which we call ‘fluctuation’ of pain. This phenomenon makes the
study of pain further difficult and complicated. When researchers study these
syndromes, they see the patient today is not suffering from the usual pain or
even suffering a lot and can’t be part of study!
For
that, researchers start to look for a new way for study of pain. Animal
experiments were useful in this regard, but we can’t depend on them completely,
or in other words we need a ‘bridging’ process, which can transfer these
information to humans.
In
this way, they started to think about making experimental models for pain in
human being.
Experimental
model of pain:
From
the start of introducing experimental pain models to the world of research
until now they used mainly 4 different kinds of stimulators to do that:
1- Physical stimulators: like heat and cold.
2- Chemical stimulators: injecting pain-producing material inside the
body.
3- Mechanical stimulator: like pressure.
4- Electrical stimulators.
What
is new?
It is difficult to apply physical or mechanical
stimulation to deep tissues like the joint. And using intra-articular (inside
the joint) injection of chemical substances can lead to more problems and side
effects.
On the other hand, we have the electrical stimulation,
which was used in muscles, and skin pain models, but never, according to our
knowledge, in the temporomandibular joint or other joints.
What
is after that?
After electrical stimulation of the pain, we need to
determine the characters of this evoked pain, the nature of sensitivity develop
in the human and the reflex of the body toward this.
In this regard, many measures would be used like sensitivity
to touch and pressure, and referred pain away from the simulation site.
This stimulation would be carried out in skin,
muscles, and joints, and in this way we can make a comparison between these
three different tissues.
In following part of the research, a medicine could be
used to get off this pain and be compared with its effect on the patients who
are suffering from naturally occurring disorder.
Further
questions:
- Is it true women suffer from pain more than men?
- Is there difference between the healthy subject and
the patient regarding this stimulation, and if there is some differences, why?
- Are drugs used for treatment of pain have the same
effect in both healthy and patient subjects or not?
These are some questions that we are going to answer
or try to find an answer.