title: [The influence of age upon circadian rhythm of human pulp sensibility].
abstract: OBJECTIVE
  To explore the influence of age on the circadian rhythm of pulp sensibility, guide the diagnosis and treatment of dental and endodontic diseases.
  
  
  METHODS
  The first lower molars of young, middle-aged, and aged volunteers were inspected for the threshold of pulp sensitivity. Each inspection was implemented every 4 hours earlier, totally 7 times during 24 hours. All values of pulp sensibility threshold from each volunteer were analyzed by Halberg methods for cosinor-rhythmometry. The chronobiology characteristics of pulp sensibility were compared among young, middle-aged, and aged.
  
  
  RESULTS
  The pulp sensibility threshold values of the young, middle-aged, and aged indicated to have the circadian rhythm alternation in period of 24 hours, with fitting well to a cosine curve. The trend of rhythm curve was similar to all three age groups. The acrophase and bathyphase appeared at 0:00 and 12:00 separately. The values and amplitudes of pulp threshold sensibility showed to be: young>aged> middle-aged.
  
  
  CONCLUSIONS
  The circadian rhythm of pulp sensibility changes according with age. The pulp sensibility threshold value is lower in aged people than in the young, and the lowest sensibility threshold is in middle-aged people. Besides, the extent of rhythm fluctuation is the least in middle-aged people.
authors: Department of Geriatric Dentistry, West China School of Stomatology, Sichuan University, Chengdu 610041, China.
authors: Si-jing
authors: SJ
authors: Xie
authors: Bin
authors: B
authors: Guo
authors: Xue-dong
authors: XD
authors: Zhou
authors: Ke-hua
authors: KH
authors: Que
authors: Zhen
authors: Z
authors: Xu
authors: Zheng-rong
authors: ZR
authors: Wang
authors: Xiu-mei
authors: XM
authors: Chen
mesh_terms: D000328:Adult; D000368:Aged; D000369:Aged, 80 and over; D000375:Aging / Q000502:physiology*; D002940:Circadian Rhythm / Q000502:physiology*; D003782:Dental Pulp / Q000502:physiology*; D003788:Dental Pulp Diseases / Q000175:diagnosis / Q000503:physiopathology / Q000628:therapy; D005260:Female; D006801:Humans; D008297:Male; D008875:Middle Aged; D055815:Young Adult