title: Effect of restraint stress on the progression of experimental periodontitis in rats.
abstract: 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.
  
  
  CONCLUSIONS
  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.
authors.affiliation: Department of Periodontology, School of Dentistry, Aichi-gakuin University, Nagoya, Aichi, Japan.
authors.forename: Tetsuo
authors.initials: T
authors.lastname: Takada
authors.forename: Nobuo
authors.initials: N
authors.lastname: Yoshinari
authors.forename: Shin
authors.initials: S
authors.lastname: Sugiishi
authors.forename: Hitoshi
authors.initials: H
authors.lastname: Kawase
authors.forename: Takashi
authors.initials: T
authors.lastname: Yamane
authors.forename: Toshihide
authors.initials: T
authors.lastname: Noguchi
mesh_terms: D000324:Adrenocorticotropic Hormone / Q000097:blood; D016301:Alveolar Bone Loss / Q000503:physiopathology; D000818:Animals; D001284:Atrophy; D001786:Blood Glucose / Q000032:analysis; D003345:Corticosterone / Q000097:blood; D004195:Disease Models, Animal; D018450:Disease Progression; D004837:Epinephrine / Q000097:blood; D017823:Furcation Defects / Q000503:physiopathology; D008297:Male; D010518:Periodontitis / Q000503:physiopathology*; D011897:Random Allocation; D051381:Rats; D017208:Rats, Wistar; D012149:Restraint, Physical; D013154:Spleen / Q000473:pathology; D013312:Stress, Physiological / Q000097:blood / Q000503:physiopathology*; D013315:Stress, Psychological / Q000097:blood / Q000503:physiopathology; D013950:Thymus Gland / Q000473:pathology
chemical_list: D001786:Blood Glucose; D000324:Adrenocorticotropic Hormone; D003345:Corticosterone; D004837:Epinephrine