Ja. Bosch et al., PSYCHOLOGICAL STRESS AS A DETERMINANT OF PROTEIN-LEVELS AND SALIVARY-INDUCED AGGREGATION OF STREPTOCOCCUS-GORDONII IN HUMAN WHOLE SALIVA, Psychosomatic medicine, 58(4), 1996, pp. 374-382
Several pathologies of the oral cavity have been associated with stres
s, so we investigated salivary-induced aggregation during psychologica
l stress. In addition, salivary total protein, alpha-amylase, and secr
etory immunoglobulin A (s-IgA) were assessed. In this longitudinal stu
dy, 28 dental students provided unstimulated whole saliva during 10 mi
nutes before an academic examination and subsequently 2 weeks and 6 we
eks later in a nonstress situation. The effect of whole saliva on the
aggregation of Streptococcus gordonii (HG 222) was determined spectrop
hotometrically. The results show a significant stress-mediated increas
e of salivary total protein concentration, alpha-amylase activity, amy
lase/protein ratio, alpha-amylase output, s-IgA concentration, and s-I
gA output. There was also a trend for increased total protein output,
whereas salivary flow rate was unchanged. The aggregation of S. gordon
ii in whole saliva collected before examination was 13.1%, whereas the
aggregation in whole saliva collected during nonstress was 23.3%, Thi
s reduction was statistically significant (p < .01). Furthermore, the
decrease in bacterial aggregation was related to the increase in state
-anxiety (p < .05). The reduction in aggregation of S. gordonii under
stress was not correlated with changes in salivary flow rate, s-IgA co
ncentration, total protein concentration, or alpha-amylase activity. T
hese results suggest that acute psychological stress exerts its influe
nce on both salivary composition and salivary function. Reduced bacter
ial aggregation may be a contributing factor in the often reported rel
ationship between stress and impaired oral health.