title: Prediction of pain in orthodontic patients based on preoperative pain assessment.
abstract: OBJECTIVE
  To investigate whether pretreatment assessment of experimental pain can predict the level of pain after archwire placement.
  
  
  METHODS
  One hundred and twenty-one general university students seeking orthodontic treatment were enrolled in this study. A cold pressor test was performed to estimate the pain tolerance of subjects before treatment. Self-reported pain intensity was calculated using a 10 cm visual analog scale during the 7 days after treatment. The relationship between pain tolerance and orthodontic pain was analyzed using Spearman's correlation analysis.
  
  
  RESULTS
  The maximum mean level of pain intensity occurred at 24 hours after bonding (53.31±16.13) and fell to normal levels at day 7. Spearman's correlation analysis found a moderate positive association between preoperative pain tolerance and self-reported pain after archwire placement (P<0.01). There was no significant difference in pain intensity between male and female patients at any time point (P>0.05).
  
  
  CONCLUSIONS
  A simple and noninvasive preoperative sensory test (the cold pressor test) was useful in predicting the risk of developing unbearable pain in patients after archwire placement. Self-reported pain after archwire placement decreased as individual pain tolerance increased.
authors.affiliation: Periodontic Department, School and Hospital of Stomatology, People's Republic of China.
authors.forename: Baoyu
authors.initials: B
authors.lastname: Zheng
authors.affiliation: Oral and Maxillofacial Surgery Department, School and Hospital of Stomatology, People's Republic of China.
authors.forename: Manman
authors.initials: M
authors.lastname: Ren
authors.affiliation: Orthodontic Department, School and Hospital of Stomatology, Wenzhou Medical University, Wenzhou, Zhejiang, People's Republic of China.
authors.forename: Feiou
authors.initials: F
authors.lastname: Lin
authors.affiliation: Pedodontic Department, School and Hospital of Stomatology, Wenzhou Medical University, Wenzhou, Zhejiang, People's Republic of China.
authors.forename: Linjie
authors.initials: L
authors.lastname: Yao
keywords: cold pressor test; intensity; self-reported