Relationships of personality traits and stress to gingival status or soft-tissue oral pathology: an exploratory study

Investigation of the levels of different salivary stress markers in chronic periodontitis patients

BACKGROUND AND AIM

In this study, we aimed to determine the salivary levels of cortisol, α-amylase, β-endorphin, and chromogranin (CgA) in saliva and to investigate their relationship with periodontitis.

METHODS

Thirty-seven female and 43 male periodontitis patients who presented to the Periodontology Department of the XXX University Faculty of Dentistry participated in the study. The individuals were divided into three groups: mild, moderate, or severe chronic periodontitis. Plaque index (PI), gingival index (GI), clinical attachment loss (CAL), and probing depth (PD) measurements were recorded for all the participants. All participants underwent the State-Trait Anxiety Inventory test (STAI 1 and 2). Between 09:00 and 11:00 a.m., saliva samples from the participants were collected into tubes within an average of five minutes.

RESULTS

Higher cortisol measurements were detected in the saliva samples of participants with severe chronic periodontitis than in those who had mild chronic periodontitis (P < 0.05). There were statistically significant age differences among patients with mild-moderate, moderate-severe, and mild chronic periodontitis, the severity of the disease increasing with age (P < 0.05). There was also a positive correlation between STAI 1 stress scores and cortisol levels. Similarly, there was a positive correlation between CAL and cortisol levels (P < 0.05). However, a significant difference was found among groups only in terms of salivary cortisol levels (P < 0.05).

CONCLUSION

Within the limitations of this study, there was found to be a relationship between saliva cortisol levels and periodontitis and between salivary cortisol levels and stress.

Usefulness of salivary alpha amylase as a biomarker of chronic stress and stress related oral mucosal changes - a pilot study

Introduction: Salivary biomarkers are suggested to provide a reliable, noninvasive and objective measurement of chronic psychosocial stress and helps in assessment of pivotal role of stress in causation or precipitation of multitude of health problems. Objectives: To evaluate the usefulness of salivary alpha amylase activity as an objective indicator of chronic stress and to find out any correlation between stress- related mucosal complaints and its levels. Study Design: Study was conducted among 50 subjects suffering from chronic stress related problems and 50 non-stressed individuals who were screened with a psychometric questionnaire. Brief case history and oral examination was carried out and about one ml of unstimulated saliva was collected. Salivary alpha amylase levels estimated were compared between study and control group and between subjects with and without oral mucosal changes using non parametric Mann Whitney U test. Results: There was statistically significant higher salivary alpha amylase levels in study group (p =.002) and salivary alpha amylase between the oral mucosal complaints group and without oral mucosal complaints group within the total study population were found to be statistically significant (p=0.045). Conclusions: Salivary amylase activity increases in patients with chronic psychosocial stress and may be used as a biomarker of chronic stress, but it may not be an indicator to suggest the development of stress related oral mucosal changes.

Key words:Salivary biomarker, salivary alpha amylase, psychosocial stress, sympathetic nervous system, oral mucosal changes.

Influence of personality traits on gingival health

Background:

The maintenance of good oral hygiene is considered a salient issue in dental health promotion. Personality is the combination of characteristics or qualities that form an individual's distinctive character. Various personality traits have been proposed to influence the oral health. The purpose of the present study was to assess the influence of personality characteristics using questionnaire on oral hygiene performance and gingival health.

Materials and Methods:

In total, 155 patients were subjected to personality questionnaire using Eysenck Personality Questionnaire. Clinical parameters such as Patient oral hygiene performance index and gingival index were recorded. Based on Eysenck Personality Questionnaire, the subjects were divided into three groups: Psychoticism, extroversion, and neuroticism.

Results:

Data analysis showed that subjects in psychoticism and neuroticism groups displayed moderate gingivitis, whereas subjects in extroversion group had severe gingivitis. Subjects in all the three groups demonstrated poor oral hygiene status. No statistically significant relation was found.

Conclusions:

A considerable clinical correlation was observed between the different personality traits and gingival health status of the subjects. It was not statistically significant. Further trials need to be conducted so as to ascertain this association so that psychological interventions may be undertaken to improve the oral hygiene condition of the population.

Restraint stress enhances alveolar bone loss in an experimental rat model

BACKGROUND AND OBJECTIVE

The purpose of the present study was to examine the effects of restraint stress on periodontal breakdown resulting from Porphyromonas gingivalis-challenged periodontitis in rats.

MATERIAL AND METHODS

To examine the influence of restraint stress on periodontal breakdown, rats were orally challenged with the periodontal pathogen P. gingivalis. Twenty male, specific pathogen-free (SPF) 3-wk-old, Sprague-Dawley rats were divided into four groups: group A (controls), group B (exposed to restraint stress for 12 h/d for 22 d), group C (orally challenged with P. gingivalis), and group D (exposed to restraint stress for 12 h/d for 22 d and orally challenged with P. gingivalis). After 22 d, all animals were killed. The distance from the alveolar bone crest to the cemento-enamel junction was determined, concentrations of adrenocorticotropic hormone were measured as stress markers, and atrophy of the thymus and spleen were assessed. In addition, the furcation area of the maxillary molars was examined histologically, while gingival cytokine gene expression was assessed by mRNA using reverse transcription-polymerase chain reaction (RT-PCR).

RESULTS

In the restrained group, all stress markers were elevated, and the thymus and spleen were atrophied. Combined restraint stress and oral challenge with P. gingivalis resulted in significantly higher bone loss, and osteoclasts were observed. RT-PCR analysis revealed low cytokine gene expression in the restrained groups.

CONCLUSION

These results suggest that the presence of restraint stress significantly enhances the progression of P. gingivalis-challenged periodontitis in rats.

Modulation of clinical expression of plaque-induced gingivitis: effects of personality traits, social support and stress

BACKGROUND

Studies have shown an association between an acute stressful event and gingivitis. However, the possible effects of personality traits associated with stress resistance/susceptibility and current level of stress on the clinical expression of plaque-induced inflammation remain to be examined. The aim of this study was to characterize the subject-based clinical behaviour of the gingiva during experimental gingivitis in relation to personality profile, psychological stress and coping behaviour.

METHODS

Ninety-six systemically and periodontally healthy subjects (mean age: 23.6+/-1.7 years), 46 males and 50 females, non-smokers, participated in a randomized, split-mouth, localized experimental gingivitis trial. Prior to the trial, subjects were asked to complete self-administered questionnaires evaluating personality traits (Hardiness scale and Courtauld Emotional Control Scale), subjective stress (Visual Analogue Scale-Total Distress), social support (Multidimensional Scale of Perceived Social Support, MSPSS) and life events (Life Experiences Survey (LES)). The influence of psychosocial factors was investigated in the overall population as well as in two sub-populations with different inflammatory response to plaque accumulation.

RESULTS

No significant relationships were found between gingival inflammation variables and psychological measures. No significant differences were detected between subjects with different susceptibilties to plaque-associated gingivitis for any considered psychological variable. A significant association between plaque variables and LES (negative) or MSPSS (positive) was found; however, the variance explained by the model was low.

CONCLUSIONS

Differences in the current level of stress and psychosocial variables indicative of stress susceptibility do not account for variability in plaque accumulation and gingival inflammation during experimental gingivitis in young adults.

Effect of Restraint Stress on the Progression of Experimental Periodontitis in Rats

BACKGROUND

A hypothesis of an increased risk for destructive periodontal diseases due to psychological stress has long been promoted. However, the research on stress and periodontal disease is still in its infancy. One of the reasons is thought to be that there is no suitable animal model for investigating the relationship.

METHODS

One hundred male Wistar rats were included. A nylon ligature was placed around the second right maxillary molars. The animals were then divided into group S, exposed to a restraint stress for 12 hours/day for up to 10 days, and group N, controls. Ten animals were sacrificed on days 2, 4, 6, 8, and 10. Blood samples were taken, and the blood glucose level and the concentrations of adrenocorticotropic hormone, corticosterone, and adrenaline were measured as the markers of stress. The atrophies of the thymus and the spleen were measured. The furcation area of the second maxillary molars was examined histologically and histometrically.

RESULTS

In group S, all values of stress markers were increased, and the thymus and the spleen were atrophied. Whereas group N showed only slight alveolar bone resorption, a marked alveolar bone resorption occurred in group S between days 8 and 10. An increase in beaded nerve terminals occurred around the vessels in the furcation area of group S.

CONCLUSION

The results of the present study suggest that the restraint stress modulates the progression of periodontal inflammation and that this rat model is suitable for investigating the association between stress and periodontal disease.

Stress as a determinant of saliva-mediated adherence and coadherence of oral and nonoral microorganisms

OBJECTIVE

The mucosal secretory proteins, such as the salivary proteins, play a key role in the acquisition and regulation of the mucosal microflora. Most notably, some microorganisms utilize the host's secretory proteins to adhere to the mucosa; a first step in colonization and infection. The secretory proteins also influence colonization by affecting the binding among microorganisms, a process denoted as coadherence. Previously we reported that acute stressors cause specific changes in saliva composition. The present study investigated to what extent these changes influence saliva-mediated microbial adherence and coadherence (ex vivo).

METHODS

Thirty-two male undergraduates provided unstimulated saliva before and during a control condition and two stressors: A memory test and a surgery video presentation. We used saliva-coated microplates to test the adherence of bacteria for which the oral cavity is either a natural reservoir (eg, viridans streptococci) or a portal of entry (eg, Helicobacter pylori). We also tested the saliva-mediated co-adherence between Streptococcus gordonii and the yeast Candida albicans. Correlation analyses were performed to determine the relationships between changes in microbial adherence and the concentrations of potential salivary ligands, viz. cystatin S, the mucins MUC5B and MUC7, S-IgA, lactoferrin, alpha-amylase, and total salivary protein.

RESULTS

During the memory test, saliva-mediated adhesion of Streptococcus sanguis, Streptococcus gordonii, and H. pylori increased, whereas the coadherence of C. albicans with S. gordonii decreased. During the surgical video presentation the saliva-mediated adherence of H. pylori, S. sanguis, and Streptococcus mitis increased. These changes were independent of salivary flow rate, but correlated with specific changes in salivary protein composition.

CONCLUSION

The results show that even moderate stressors, by altering the activity of the mucosal secretory glands, may affect microbial colonization processes such as adherence and coadherence. This study hereby presents a mechanism by which stress may affect the mucosal microflora and susceptibility to infectious disease.

Personality traits predict self-referral of young male adults with musculoskeletal complaints to a general practitioner

OBJECTIVE

To investigate the effects of personality traits on self-referral to a general practitioner (GP).

METHODS

217 male soldiers who underwent advanced training course filled the Eysenck Personality Questionnaire-Revised (EPQ-R) and the Perceived Stress Scale and were followed up for a period of 14 weeks. Every soldier who self-referred to the clinic was physically examined by a GP. The major complaint and the GP's diagnosis were documented.

RESULTS

106 of the 217 soldiers self-referred. Self-referred soldiers had significantly (P=.02) higher levels of extraversion than soldiers who did not. Specifically, higher levels of extraversion were evident among soldiers who self-referred with musculoskeletal complaints (P<.05). No significant difference in stress levels was found between soldiers who self-referred and those who did not.

CONCLUSIONS

These findings underscore the association between extraversion and musculoskeletal complaints among young adult males and suggest that psychological variables should be taken under consideration in the prevention and treatment of orthopedic problems.

The effect of chronic emotional stress on the humoral immune response to Porphyromonas gingivalis in mice

Previous studies have shown that psychological stress plays a significant role in the outcome of infectious diseases, but data related to the effect of stress on periodontal infection is limited. The present study was designed to test the impact of emotional stress on the humoral immune response to the periodontal pathogen Porphyromonas gingivalis in a mouse model of local inflammation. Chambers constructed from titanium wire were implanted in the subcutaneous dorsolumbar region of mice. All mice were immunized with P. gingivalis followed by an intrachamber challenge with the bacteria. One group of mice was used as control, while the other two experienced experimental stress conditions (isolation/restraint stress). Stress-1 group was stressed during the immunization period, while Stress-2 group was stressed during the local challenge period. Chamber exudates and serum were collected and analyzed for levels of anti-P. gingivalis antibodies (IgG, IgG1 and IgG2a). The levels of serum antibodies to P. gingivalis were not different between the three tested groups, excluding increased levels of IgG2a in Stress-1 group at baseline. The levels of antibodies in the chamber exudates were significantly lower in the stressed groups at baseline, but higher at d 7. The IgG1 to IgG2a ratio was significantly higher in the control group compared with the two stressed groups. The findings of the present study suggest that chronic psychological stress had a marked impact on the localized response to P. gingivalis challenge. The lower IgG1/IgG2a ratio observed in the stress groups suggests elevated Th1 response during stress.

Experimental stress suppresses recruitment of macrophages but enhanced their P. gingivalis LPS-stimulated secretion of nitric oxide

BACKGROUND

Epidemiological studies have suggested that stress can alter the onset and progression of periodontal disease. However, the mechanisms involved are not clear. The present study was designed to examine whether the functional response of mouse macrophages stimulated by Porphyromonas gingivalis lipopolysaccharide (LPS) is affected by experimental stress, and to investigate the role of corticosterone (CS) in the stress-related effects.

METHODS

Two models of stress were used: emotional (isolation) and physical (cold). We measured thioglycollate-induced macrophage recruitment in vivo, and LPS-induced nitric oxide (NO) secretion by the macrophages in vitro. Two groups of mice were exposed to the stress conditions: isolation or cold. A third group was injected daily with CS, and a fourth group was used as a control (no stress). After 3 days of stress conditions, thioglycollate was injected into the peritoneal cavity. Four days later, peritoneal macrophages were isolated, counted, and cultured. The secretion of NO by the cultured cells was evaluated with and without P. gingivalis LPS stimulation.

RESULTS

The number of cells in the peritoneal lavage of stressed mice was significantly reduced in comparison to macrophages isolated from non-stressed animals. The number of macrophages from CS-treated mice did not differ from controls. NO secretion from unstimulated macrophages did not differ between the stressed and control groups. Stimulation of the macrophages with P. gingivalis LPS significantly enhanced NO secretion by macrophages from the control and stressed animals, but not by the CS-treated group. NO levels secreted by P. gingivalis-stimulated cells from the two stressed groups were significantly higher than the levels secreted by controls, and the isolation group released significantly higher levels than the cold group. Stimulation of the macrophages with P. gingivalis LPS and interferon (IFN)-gamma resulted in enhanced NO secretion in the 4 groups compared to LPS alone, with no significant differences between the groups.

CONCLUSIONS

The results suggest that experimental stress modulates the response of macrophages to inflammatory stimulants, and that CS is not the sole mediator involved. The presence of IFN-gamma in the culture may mask the functional differences induced by stress. The stress-induced upregulation of NO secretion might be involved in the accelerated periodontal destruction in stressed subjects.

The Effect of Stress on the Inflammatory Response toPorphyromonas gingivalisin a Mouse Subcutaneous Chamber Model

BACKGROUND

The impact of emotional stress on the outcome of infectious diseases was studied in animal models and humans, but data related to the effect of stress on periodontal infection are limited. Using the subcutaneous chamber model in mice, the present study was carried out to investigate the effect of stress on the host response to Porphyromonas gingivalis.

METHODS

Mice with subcutaneous chambers (2 per animal) were divided into 4 treatment groups: cold-stress; isolation-stress; corticosterone (CS)-injected; and controls. On the third day of stress conditions, heat-killed P. gingivalis were injected into the chambers. The chambers were sampled 1 and 5 days later and analyzed for leukocyte number, tumor necrosis factor (TNF)-alpha levels, and interferon (IFN)-gamma levels.

RESULTS

Injection of P. gingivalis induced the migration of leukocytes into the chambers and increased the intrachamber levels of IFN-gamma and TNF-alpha. There were no significant differences in cell number and IFN-gamma levels between the different treatment groups, but the levels of TNF-alpha were significantly lower in the isolation-stress and cold-stress groups compared to control animals. CS-injected animals were not different from controls. In addition, the levels of TNF-alpha in the stressed animals were lower on the fifth day post-injection than on the first day, but not in the CS and control group.

CONCLUSIONS

The results suggest that the levels of TNF-alpha induced by P. gingivalis in the infection site are downregulated in stressed animals, and CS is not the sole mediator responsible. The stress-induced reduction in TNF-alpha levels might have an impact on the pathogenesis of periodontal disease in humans experiencing emotional stress.