title: Descriptive study of dental injury incurred by junior high school and high school students during participation in school sports clubs.
abstract: OBJECTIVE
  Students often injure their teeth during participation in school-based sports clubs. This study examined the frequencies and types of dental injuries sustained at school sports clubs and compared the risk of dental injury among different sports.
  
  
  METHODS
  Based on injury statistics from the Japan Sport Council of the junior high schools and high schools in seven prefectures during fiscal year 2006, the risk of dental injury was estimated using a rate ratio (RR) by calculating the ratio of occurrence of dental injury under various circumstances.
  
  
  RESULTS
  The RRs of exercise-related dental injury for boys and girls in junior high school were 0.7 (P < 0.001) and 1.3 (P < 0.05), respectively, and for those in high school were 2.6 (P < 0.001) and 2.7 (P < 0.001), respectively. In junior high school, softball (RR = 7.7) for boys and handball (RR = 3.9) for girls commonly led to dental injuries. In high school, Japanese-style wrestling (RR = 18.5) and rugby (RR = 7.3) for boys and handball (RR = 6.5) for girls had high risks for dental injury. Crown fracture was the predominant dental injury among boys and girls attending both junior high school and high school. The proportion of alveolar fracture was higher in school sports clubs than outside school sports clubs among high school boys. Contact or limited-contact sports had significantly higher risks for dental injuries than did noncontact sports.
  
  
  CONCLUSIONS
  The results of this study suggest that teachers and administrators at schools should pay attention to the risk of dental injury among students participating in high-risk sports.
authors.affiliation: Department of Preventive Dentistry and Dental Public Health, School of Dentistry, Aichi Gakuin University, Nagoya, Japan.
authors.forename: Toshiya
authors.initials: T
authors.lastname: Nonoyama
authors.affiliation: Department of Preventive Dentistry and Dental Public Health, School of Dentistry, Aichi Gakuin University, Nagoya, Japan.
authors.forename: Yoshihiro
authors.initials: Y
authors.lastname: Shimazaki
authors.affiliation: School of Dentistry, Aichi Gakuin University, Nagaya, Japan.
authors.forename: Haruo
authors.initials: H
authors.lastname: Nakagaki
authors.affiliation: Department of Preventive Dentistry and Dental Public Health, School of Dentistry, Aichi Gakuin University, Nagoya, Japan.|Tsuge Dental Clinic, Ena, Japan.
authors.forename: Shinpei
authors.initials: S
authors.lastname: Tsuge
mesh_terms: D000367:Age Factors; D000539:Alveolar Process / Q000293:injuries; D001265:Athletic Injuries / Q000453:epidemiology* / Q000209:etiology; D006801:Humans; D007564:Japan / Q000453:epidemiology; D012574:Schools / Q000706:statistics & numerical data; D012737:Sex Factors; D013177:Sports; D013334:Students / Q000706:statistics & numerical data; D018677:Tooth Injuries / Q000453:epidemiology* / Q000209:etiology
keywords: Dental injury; high school students; junior high school students; school sports club