title: Prevalence and associated factors for temporomandibular disorders in Chinese civilian pilots.
abstract: OBJECTIVE
  Piloting is a special profession with prolonged stress, which could induce the occurrence of TMD. This sample is useful to reduce the effect of confounders in the analyses. Based on this, the present study aims to determine the prevalence and associated factors for TMD in civilian pilots of China.
  
  
  METHODS
  A cross-sectional epidemiological survey was carried out in 616 male subjects (aged 23-52 years). The questionnaire included general information, chewing preference (bilateral or unilateral), and Trait Anxiety section of Spielberger State-Trait Anxiety Inventory (STAI-T). The clinical examination contained TMD screening per research diagnostic criteria for TMD and diagnosis of sleep bruxism per American Academy of Sleep Medicine standards. The level of statistical significance was set at P ≤ 0.05.
  
  
  RESULTS
  The program was conducted from June 2012 to April 2013, in which period, and the percentage of TMD in the samples we examined was 33.3 % (=205/616). Only high anxiety (OR 2.48; 95 % CI 1.25-4.90) and unilateral chewing preference (OR 12.67; 95 % CI 7.77-20.65) were the most significant associated factors with TMD. Also, salivary cortisol and the STAI-T score had a significant correlation (r = 0.47, P < 0.001).
  
  
  CONCLUSIONS
  It was more reliable to study the associated factors on TMD with the exclusion of the possible confounding factors, and only unilateral chewing preference and psychological stress had a significant association with TMD. In addition, the salivary cortisol levels might assist to assess psychological stress in epidemiological research.
authors.affiliation: State Key Laboratory of Oral Diseases, Sichuan University, Chengdu, 610041, China.
authors.forename: Qing
authors.initials: Q
authors.lastname: Yu
authors.affiliation: State Key Laboratory of Oral Diseases, Sichuan University, Chengdu, 610041, China.
authors.forename: Yang
authors.initials: Y
authors.lastname: Liu
authors.affiliation: State Key Laboratory of Oral Diseases, Sichuan University, Chengdu, 610041, China.
authors.forename: Xi
authors.initials: X
authors.lastname: Chen
authors.affiliation: State Key Laboratory of Oral Diseases, Sichuan University, Chengdu, 610041, China.
authors.forename: Duanjing
authors.initials: D
authors.lastname: Chen
authors.affiliation: State Key Laboratory of Oral Diseases, Sichuan University, Chengdu, 610041, China.
authors.forename: Lu
authors.initials: L
authors.lastname: Xie
authors.affiliation: State Key Laboratory of Oral Diseases, Sichuan University, Chengdu, 610041, China.
authors.forename: Xiao
authors.initials: X
authors.lastname: Hong
authors.affiliation: Medical Center of Shenzhen Airlines, Shenzhen, 518128, China.
authors.forename: Xingyuan
authors.initials: X
authors.lastname: Wang
authors.affiliation: Medical Center of Shenzhen Airlines, Shenzhen, 518128, China.
authors.forename: Haili
authors.initials: H
authors.lastname: Huang
authors.affiliation: State Key Laboratory of Oral Diseases, Sichuan University, Chengdu, 610041, China. yhyang6812@scu.edu.cn.
authors.forename: Haiyang
authors.initials: H
authors.lastname: Yu
mesh_terms: D000328:Adult; D000337:Aerospace Medicine / Q000706:statistics & numerical data*; D000401:Aircraft; D001007:Anxiety / Q000150:complications* / Q000453:epidemiology / Q000503:physiopathology; D002681:China / Q000453:epidemiology; D003430:Cross-Sectional Studies; D016021:Epidemiologic Studies; D006801:Humans; D006854:Hydrocortisone / Q000032:analysis; D008297:Male; D008409:Mastication; D008875:Middle Aged; D009784:Occupational Diseases / Q000453:epidemiology* / Q000503:physiopathology / Q000523:psychology; D015995:Prevalence; D012307:Risk Factors; D012463:Saliva / Q000737:chemistry; D020186:Sleep Bruxism / Q000150:complications / Q000453:epidemiology / Q000523:psychology; D013315:Stress, Psychological / Q000453:epidemiology* / Q000503:physiopathology; D011795:Surveys and Questionnaires; D013705:Temporomandibular Joint Disorders / Q000453:epidemiology* / Q000523:psychology; D055815:Young Adult
chemical_list: D006854:Hydrocortisone
keywords: Associated factors; Chinese; Civilian pilots; Cross-sectional studies; Prevalence; Temporomandibular disorders