Association Between Oxidative Damage Markers and Self-Reported 
Temporomandibular Dysfunction Symptoms in Patients with Chronic Fatigue 
Syndrome

J Chronic Fatigue Syndrome, Vol: 12 Issue: 3, 
Cover Date: 2004, Publication Date: 2005, Copyright Date: 2004,P 45-61

Ross S. Richards, PhD; Neil R. McGregor, MDSc, PhD; Timothy K. 
Roberts. PhD

Ross S. Richards is Faculty of Health Studies, Charles Sturt University, 
Albury, NSW, Australia.

Neil R. McGregor is Faculty of Dentistry, University of Sydney, Westmead 
Hospital, Westmead, Australia and also affiliated with Bio21 Molecular 
Science and Biotechnology Institute, University of Melbourne, 2 Park 
Street, Parkville, Victoria 3012, Australia.

Timothy K. Roberts is affiliated with the School of Environmental and Life 
Sciences, University of Newcastle, Callaghan, Australia.

Address correspondence to: Dr. Neil R. McGregor, Bio21 Molecular Science 
and Biotechnology Institute, University of Melbourne, 2 Park Street, 
Parkville, Victoria 3012, Australia (E-mail: binrm@bigpond.com).

The authors are grateful to the staff of the Hunter Area Pathology Service 
for the estimation of full blood count and serum vitamin B12, ferritin and 
iron and the University of Newcastle, including Dr. R. H. Dunstan, for 
their constructive comments. They also thank the Gideon Lang Foundation, 
the Judith Mason CFS Research Grant and the Lower Hunter CFS/ME Fundraising 
Association for their financial support and members of the Hunter Valley 
branches of the ME/CFS society of NSW for their support and encouragement.


Full blood counts, erythrocyte sedimentation rate (ESR), C-reactive protein 
(CRP), haematinics and markers for oxidative stress were measured on 
thirty-three patients diagnosed with chronic fatigue syndrome (CFS) and 
twenty-seven age and sex matched controls.

The CFS patients had increased prevalence of symptoms of temporomandibular 
dysfunction (TMD). Jaw muscle pain was associated with increases in 
methaemoglobin (P < .002), ferritin (P < .02) and malondialdehyde (P < 
.007) whilst temporomandibular joint (tmj) clicking and/or locking was 
associated with increases in methaemoglobin (P < .001), malondialdehyde (P 
< .05) and vitamin B12 (P < .02) levels. Multiple regression analysis found 
methaemoglobin to be the principle component associated with TMD symptoms 
in the CFS patients. Increases in scalar severity responses to jaw muscle 
pain and TMJ clicking and/or locking were positively correlated with 
methaemoglobin by multiple regression.

These data indicate that oxidative stress due to excess free radical 
formation was associated with jaw muscle pain in CFS patients and suggest 
that these symptoms were likely to be associated with a pathogen-associated 
aetiology.


Keywords: Oxidative damage, Methemoglobin, Malondialdehyde, Vitamin B12, 
TMD syndrome, chronic fatigue syndrome, Pain aetiology, TMD aetiology