A R T IC L E S
Relationship between allergy and bruxism in patients with myofascial pain-dysfunction syndrome Ronald E. Olson, PhD Daniel M. Laskin, DDS, MS
The relationship betw een allergy and bruxism was exa m in ed in three groups: patients with m yofascial pain-dysfunction, patients with organic disorders of the tem porom andibular joint, and patients without tem porom andibular joint disorders.
A
JL 1L Ithough
there are several ways in which the myofascial pain-dys function (MPD) syndrome can be de veloped in individuals, the psychophysiologic theory proposes that, in most patients, the syndrome devel ops as a result of muscle fatigue pro duced by stress-related m uscle hyperactivity.1 Clenching and grind ing the teeth are common forms of parafunctional oral habits that pro duce muscle hyperactivity. In 1977, Marks2 reported, in his inv e s t i g a t i o n o f a l l e r g i c and nonallergic children, a threefold greater incidence of bruxism in the allergic child. He postulated that in termittent allergic edema of the eustachian tube during sleep reflexly triggered the bruxing habit. As the oral habit of grinding teeth at night has been implicated in the develop ment of MPD syndrome in adults, the current study was undertaken to examine the incidence of allergy and bruxism in a sample of patients with
MPD syndrome, a comparison sam p le o f p a t ie n t s w ith o r g a n ic temporomandibular joint (TMJ) dis orders, and a sample of dental clinic patients without TMJ dysfunction.
Method Standard medical questionnaires of 100 patients diagnosed as having MPD syndrome, 89 women and 11 men; 50 patients with organic TMJ disorders, 44 women and 6 men; and 150 dental clinic patients without TMJ dysfunction, 133 women and 17 men, were examined for self-reports of allergy and bruxism. The essential diagnostic criteria for MPD syn drome were pain and tenderness in or around the TMJ. Limitation of jaw function, clicking or popping sounds in the joint, or both, although cor roborative symptoms of MPD syn drome, were not in themselves suffi cient to include a patient in the study sample. The patients with TMJ dis
orders had radiographic, clinical, or laboratory evidence of organic dis ease.
Results Self-reports of allergy and bruxism for the three groups of patients are presented in the Table. A chi-square analysis of the data indicated a sig nificant difference between the selfreports ofthese groups (x2 = 17.72, d f = 6, P < .02). To clarify the nature of this difference, separate comparisons between the groups were made. There were no significant differences between the patients with MPD syn drome and TMJ disorders (x2 = 1.84, d f = 3, N S). However, when the group w ith MPD syndrome was compared with the clinic patients without TMJ dysfunction, there was a significant difference (x2 = 14.99, d f = 3, P < .01). The MPD patients reported more bruxism with or with out allergy than the clinic patients. There was no difference between these two groups on incidence of al lergy. There was also no significant difference in allergy between the pa tients with TMJ disorders and clinic patients (x2 = 6.61, d f = 3, NS).
Discussion The results of this study show no re lation between allergy and bruxism JADA, Vol. 100, February 1980 ■ 209
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Table ■ Self-reports of allergy and bruxism for patients with MPD syndrome, other TMJ disorders, and dental clinic patients without TMJ dysfunction.
Allergy and bruxism Allergy without bruxism Bruxism without allergy Neither bruxism nor allergy
for the three groups. Patients with MPD syndrome did report a history of bruxism significantly more often than the routine dental clinic group, but this was not related to allergy. However, it does support the concept that parafunctional habits can play a part in the cause of this syndrome. The higher incidence of bruxism in the group with TMJ disorders proba bly relates to the fact that most of these patients had osteoarthritis of the TMJ. In many of these patients,
210 « JADA, Vol. 100, February 1080
MPD N = 100 (%)
TMJ N = 50 (%)
Clinic N = 150 (%)
7 21 20 52
10 20 12 58
1 21 8 70
the degenerative joint change devel ops as a sequel to chronic MPD syn drome.3
Summary Self-reports of allergy and bruxism from 100 patients diagnosed as hav ing MPD syndrome, 50 patients with organic TMJ disorders, and 150 clinic patients without TMJ dysfunc tion were examined. Although no re lation between allergy and bruxism
was found for the three groups, pa tients with MPD syndrome reported a history of bruxism more often than did the clinic group, but this was not related to allergy. The results suggest that parafunctional habits can play a part in the etiology of MPD syn drome. This study was supported by Research Grant no. De-02899, National Institute of Dental Re search, National Institutes of Health. Dr. Olson is chief psychologist, Temporo mandibular Joint and Facial Pain Research Cen ter, and Dr. Laskin is professor and head, de partment of oral and m axillofacial surgery, University of Illinois College of Dentistry, 801 S Paulina St, PO Box 6998, Chicago, 60680. Ad dress requests for reprints to Dr. Laskin. 1. Laskin, Q.M. E tiolo gy o f the paindysfunction syndrome. JADA 79(1):147-153, 1969. 2. Marks, M.B. Recognizing the allergic per son. Am Fam Phys 16(l]:72-79,1977. 3. T oller, P.A. Tem porom andibular ar thropathy. ProcR Soc Med 67:153-159,1974.