-- UB study finds that people who develop jaw pain disorders
exhibit specific characteristics, including more trauma to the jaw,
more limitations and noises in the jaw, more headaches and
generally worse medical status
-- The findings are being published by UB School of Dental
Medicine researchers who are international authorities on aspects
of jaw pain disorders and who have developed through international
collaborations many of the most commonly used diagnostic tools
BUFFALO, N.Y. -- Millions of Americans are affected by painful
jaw problems known as TMD, temporomandibular disorders, but
predicting who is at risk has been extremely difficult.
Now, for the first time, researchers in the University at
Buffalo School of Dental Medicine are publishing a comprehensive
set of clinical characteristics that they say will lead to the
ability to identify individuals at risk for developing the painful
Their new clinical assessments will help researchers and
clinicians better understand TMD and other pain conditions, so as
to find ways to better manage and treat them.
Published in the November issue of the Journal of Pain, the UB
research results are part of the Orofacial Pain Prospective
Evaluation and Risk Assessment (OPPERA) study, available at http://www.jpain.org/issues?issue_key=S1526-5900(11)X0013-5,
which followed 3,200 initially pain-free individuals for three to
It is the largest clinical study of pain conditions and how they
develop that has ever been done.
The UB researchers, led by Richard Ohrbach, DDS, PhD, associate
professor of oral diagnostic sciences in the UB School of Dental
Medicine, have been studying pain and TMD for several decades.
Ohrbach is the lead author on the paper.
"The UB role in the project was to develop well-designed
examination procedures to help dentists and other health care
providers identify risk factors for TMD," says Ohrbach.
Ohrbach and his co-authors studied 71 different clinical
variables in 1,633 controls -- individuals who never had TMD -- and
in 185 people with chronic painful TMD.
They assessed the individuals through lengthy questionnaires
about health histories and current symptoms and through clinical
exams. Participants were from Western New York, Maryland, North
Carolina and Florida.
The UB researchers found that a very high rate of the variables
they assessed, 59 out of 71, were significantly associated with
"Our results indicate that individuals with TMD differ
substantially from the controls across almost all of the variables
we assessed," says Ohrbach.
TMD sufferers tended to have significantly higher levels of the
following variables: trauma to the jaw, non-pain symptoms in the
facial area, jaw locking and noises, and pain during such jaw
movements as chewing, smiling or talking. Ohrbach notes that while
the last two findings were clearly expected, very little has been
known about the first two findings.
In particular, the UB researchers found that TMD sufferers
reported a much higher rate of neural and sensory medical
conditions, such as earaches, tinnitus or hearing loss, fainting
and dizziness, as well as seizures due to epilepsy and other
Ohrbach said that the study also confirmed many findings that
long have been associated with TMD but which have not, until now,
been proven in a comprehensive, large-scale study.
Among these is the finding that any pain disorder, such as
headache, backache and abdominal pain, is more likely to occur in
TMD patients than in people who do not have TMD.
"Why are other pain disorders more common in people with TMD?"
asks Ohrbach. "Is it because those pain conditions predispose them
to develop TMD or do they develop TMD first and does TMD lead them
to then develop other pain disorders?"
To answer these and other related questions, Ohrbach says he and
his colleagues will next look at comorbidity.
"We'll be tracking these multiple pain disorders over time with
particular variables," he says.
Ultimately, the findings of the UB researchers and their
colleagues on the OPPERA study will be geared toward a better
understanding of pain conditions in general.
"How do we understand the pain? How do we establish a reliable
and clinically useful marker of pain so that significant pain can
be more readily diagnosed?" asks Ohrbach. "To answer these
questions, we need to have a model that puts all of the pieces
together, that takes the findings from a clinical exam, puts it
into a rigorous framework using the right assessment and diagnosis
tools in order to chart the nature of multiple physical disorders
so that we can ultimately understand how the pain is affecting the
The OPPERA study was funded by the National Institute of Dental
and Craniofacial Research.
Co-authors with Ohrbach on the paper are: Yoly Gonzalez of the
UB Department of Oral Diagnostic Sciences; Roger B. Fillingim,
University of Florida, College of Dentistry, North Florida/South
Georgia Veterans Health System; Sharon Gordon, Department of
Oral-Maxillofacial Surgery and Brotman Facial Pain Center,
University of Maryland-Baltimore, Dental School; Henry Gremillion,
Louisiana State University Health Sciences Center School of
Dentistry; Margarete Ribeiro-Dasilva, Department of Community
Dentistry and Behavioral Science, University of Florida, College of
Dentistry; Joel D. Greenspan, Department of Neural and Pain
Sciences, and Brotman Facial Pain Center; Charles Knott, Battelle
Memorial Institute; and Pei-Feng Lim, William Maixner, Flora Mulkey
and Gary Slade, all of the University of North Carolina-Chapel
The University at Buffalo is a premier research-intensive public
university, a flagship institution in the State University of New
York system and its largest and most comprehensive campus. UB's
more than 28,000 students pursue their academic interests through
more than 300 undergraduate, graduate and professional degree
programs. Founded in 1846, the University at Buffalo is a member of
the Association of American Universities.
Related story: "UB to Study Causes of Facial, Jaw Pain," http://www.buffalo.edu/news/7724