Dentaltown January 2020 - 74

for overwhelming successful symptomatic
resolution, including everything from
headaches to internal derangements of the
temporomandibular joint.
The knee-jerk reaction that opposes this
thought process suggests that occlusion is not
at all related to orofacial pain patterns. This
concept is problematic for the general dental
population that has personally witnessed
many occasions of both odontogenic and
nonodontogenic pain relieved with simple
occlusal adjustments.
The nature of causality thus becomes
critically important and needs to be examined
carefully.
This discussion is extremely timely and
long overdue, and a current TMJ thread
on Dentaltown's message boards is titled
"The End of Occlusion in TMD. A Major
Crisis Is on the Horizon." [Editor's note:
A link to this message board is embedded in
the digital version of this article online at
dentaltown.com/magazine.] The concern
is that there are those who have applied
for a specialty status of pain management
who question any role of occlusion in pain.
Where does the truth lie? Not surprisingly, perhaps somewhere in between.

TMD and occlusion
The use of the term "TMD" in any
discussion is problematic11 because it's an
umbrella "diagnosis" that is not specific and
includes a host of very different conditions.
Nevertheless, the predominance of the
evidence suggests no direct relationship
between any specific pain pattern and any
specific scheme of tooth-to-tooth contact.
Yet, as dentists, we are well aware that
changes in occlusion have resulted in either
initiation of pain or resolution of pain before
and after restorative therapy.
Despite the fact that dentistry tends to
"stipulate" occlusion, the fact remains that
studies have suggested that teeth are actually

74

JANUARY 2020 // dentaltown.com

in contact less than 20 minutes a day in the
absence of parafunction.12
In dental terminology, occlusion (a noun)
refers to the relationship of the dental scheme
when the elevators contract and bring the
teeth into contact in maximum intercuspation. Occluding (a verb) refers to the action
of dental contact. It would seem obvious,
then, that occluding and the consequential
forces that result are at issue when it comes
to possible damage to the components of
the cranial-cervicomandibular complex.
But is it that simple? Of course not.

Is bruxism caused
by occlusion?
It has been assumed and generally
thought by most all of dentistry that bruxism
causes internal derangements and orofacial
pain as well as headaches. In 1961, Ramfjord
and Ash wrote, without evidence, that
bruxism was caused by "interferences" and
thus malocclusion.13 Dawson's teachings
were clearly geared toward putting the
condyle in centric relation and eliminating
all interferences to that position. When this
type of equilibration had been completed
and the patient's symptoms had improved,
it was then assumed that the bruxism had
caused the pain and that the equilibration
had stopped the bruxism.14
The suggestion that the equilibration has
stopped the bruxism has never been proven.
In fact, Goodman and Greene demonstrated
that "mock equilibrations" were as effective
in symptom reduction as fully performed
equilibrations.15 Michelotti demonstrated
that when she added interferences (gold foil)
into the occlusal scheme of healthy females,
not only did it not produce symptoms, but
also the masseter EMG levels decreased.16

Does bruxism cause pain?
Raphael has demonstrated that people
with pain do not necessarily brux more
https://www.dentaltown.com/messageboard/thread.aspx?s=2&f=883&t=335024 http://www.dentaltown.com
Dentaltown January 2020

Table of Contents for the Digital Edition of Dentaltown January 2020
