Dentaltown January 2020 - 75

than people without pain. She goes further
to suggest that there are those with pain
who don't brux, and those who brux and
don't have pain. In fact, there are those who
brux significantly in terms of frequency
and duration and do not have any pain or
dysfunction.17
While this is irrefutable, Raphael concludes not only that bruxism does not cause
pain, but that therefore treatment toward
parafunctional control was "misguided."18
After conducting an excellent study that used
EMGs in polysomnograms to determine
the existence of bruxism in patients with
and without pain (as opposed to many past
studies, which used unreliable questionnaires)
Rafael notes the lack of the direct relationship
and concludes that because most patients
with pain did not exhibit sleep bruxism
(SB), therefore "the common belief that
SB is a sufficient explanation for myofascial
TMD should be abandoned." She further
notes that pain does not, therefore, justify
SB treatment.18
A discussion about causation and potential contributing mechanisms becomes
essential and takes us back to both Emerson's
and Campbell's quotes at the beginning of
this paper. Emerson suggested that man's
tendency was to attempt to simplify cause and
effect; Campbell's quote made it clear that
understanding pain is not simple. Pain is a
combination of not only the degree of negative
stimulus to the organism but also a complex
physiology that is not totally understood
and cannot be simply measured. Pain is not
directly related to the painful event but is a
concept with many compounding, not readily
measured or always understood, factors.
Every dentist has adjusted an occlusion
and noted a change in a patient's dental-and, often, nondental-symptoms.
Success. Every dentist has then repeated that
adjustment for another patient, only to be
surprised by a total lack of response. Failure!

It seems clear that there is no direct
relationship between bruxism and pain,
and yet certainly incorrect to suggest that
altering the forces during the bruxism event
in terms of magnitude and direction by
changing the occlusal scheme can't result
in altered symptoms.
It therefore follows that it would be
incorrect to suggest that when occlusion
is altered and the symptoms resolve that
the occlusal scheme and bruxism were the
"cause" of the pain pattern. It would be more
appropriate and accurate to suggest that the
occlusal scheme and bruxism was certainly
a contributing factor, and that the alteration
of that scheme with that particular patient's
adaptive capacity considered, helped resolve
their pain or dysfunction.
It is misguided, therefore, to suggest
that the lack of a direct relationship between
bruxism and pain would suggest that
treatment aimed at parafunctional control
and thus altering the forces of bruxism is
"misguided." ■

3.
4.

10.

11.

12.
13.
14.

15.

16.
References
1.

Emerson, R.W., Natural History of Intellect and other papers.
1904, Boston and New York: Houghton and Mifflin and
Company.
Campbell, J.N., Extension of the temporomandibular joint
space by methods derived from general orthopedic procedures.
J. Pros. Dent, 1957. 7(3): p. 386-399.

17.

18.

Fonder, A.C., The Dental Physician. 2nd ed. 1985, Rock
Falls, IL: Medical-Dental Arts. 462.
Maehara, K., T. Matsui, and F. Takada, Dental Distress
Syndrome (DDS) and Quadrant Theorem - The masticatory
System, General 'signs and Symptomatology. Journal of
Biologic Stress and Disease: Basal Facts, 1982. 5(1): p. 4-11.
Leeds, A.B. and W. May, Arthritic symptoms related to the
position of the mandible. Arizona Dental Journal, 1955.
1(6).
Costen, J.B., A syndrome of ear and sinus symptoms dependent upon disturbed function of the temporomandibular
joint. 1934. Ann Otol Rhinol Laryngol, 1934. 106(10 Pt 1):
p. 805-19.
Guichet, N.F., Biologic laws governing functions of muscles
that move the mandible. Part II. Condylar position. J Prosthet Dent, 1977. 38(1): p. 35-41.
Gelb, H., et al., The role of the dentist and the otolaryngologist in evaluating temporomandibular joint syndromes. J
Prosthet Dent, 1967. 18(5): p. 497-503.
Dawson, P.E., Optimum TMJ condyle position in clinical
practice. Int J Periodontics Restorative Dent, 1985. 5(3): p.
10-31.
Jankelson, B., Neuromuscular aspects of occlusion. Effects
of occlusal position on the physiology and dysfunction of
the mandibular musculature. Dent Clin North Am, 1979.
23(2): p. 157-68.
Nitzan, D.W., B. Kreiner, and R. Zeltser, TMJ lubrication
system: its effect on the joint function, dysfunction, and
treatment approach. Compend Contin Educ Dent, 2004.
25(6): p. 437-8, 440, 443-4 passim; quiz 449, 471.
Graf, H., Bruxism. Dent Clin North Am, 1969. 13: p. 659665.
Ramfjord, S.P., Bruxism, a clinical and electromyographic
study. J Am Dent Assoc, 1961. 62: p. 21-44.
Dawson, P.E., Temporomandibular joint pain-dysfunction
problems can be solved. J Prosthet Dent, 1973. 29(1): p.
100-12.
Goodman, P., C.S. Greene, and D.M. Laskin, Response of
patients with myofascial pain-dysfunction syndrome to mock
equilibration. Journal of the American Dental Association,
1976. 92(4): p. 755-8.
Michelotti, A., et al., Effect of occlusal interference on habitual activity of human masseter. J Dent Res, 2005. 84(7): p.
644-8.
Raphael, K.G., et al., Sleep bruxism and myofascial temporomandibular disorders: A laboratory-based polysomnographic
investigation. The Journal of the American Dental Association, 2012. 143(11): p. 1223-1231.
Raphael, K.G., Author's response. J Am Dent Assoc, 2013.
144(3): p. 244.

dentaltown.com \\ JANUARY 2020

http://www.dentaltown.com

Dentaltown January 2020

Table of Contents for the Digital Edition of Dentaltown January 2020