title: Effect of anticancer therapy on ectopic eruption of permanent first molars.
abstract: OBJECTIVE
  The purpose of this study was to investigate the association between anticancer therapy and ectopic eruption of permanent first molars (PFMs).
  
  
  METHODS
  This study evaluated 564 five- to seven-year-old patients (anticancer therapy group=76; control group=488) who had radiographs taken between October 1, 2009 and September 30, 2010. The prevalence of ectopic eruption of PFMs was compared between the anticancer therapy group and control group. In the anticancer therapy group, the association between ectopic eruption and radiation therapy, hematopoietic stem cell transplantation (HSCT), and age at the start of treatment was also evaluated.
  
  
  RESULTS
  The overall prevalence of ectopic eruption was approximately six percent, with a significantly higher rate in the anticancer therapy group (~16 percent) than in the control group (~five percent; P<.001). Supplementary radiation therapy and HSCT did not significantly influence the prevalence. Patients who started anticancer therapy after three years old, however, had a lower rate of ectopic eruption than patients who started earlier (P<.05).
  
  
  CONCLUSIONS
  The prevalence of ectopic eruption of permanent first molars increased in patients with anticancer therapy. This effect was greater in children who started anticancer therapy before they were three years old.
authors.affiliation: Korean Army Medical Corps, 5th Infantry Division, Gyeonggido, South Korea.
authors.forename: Yoonsik
authors.initials: Y
authors.lastname: Ko
authors.affiliation: Department of Pediatric Dentistry, The Institute of Oral Health Science, Samsung Medical Center, at Sungkyunkwan University School of Medicine at Seoul, South Korea.
authors.forename: Kitae
authors.initials: K
authors.lastname: Park
authors.affiliation: Department of Pediatric Dentistry School of Dentistry, Pusan National University, Dental Research Institute, at Busan, South Korea. jychaee@pusan.ac.kr jychaee@gmail.com.
authors.forename: Ji-Yeon
authors.initials: JY
authors.lastname: Kim
mesh_terms: D000367:Age Factors; D000970:Antineoplastic Agents / Q000627:therapeutic use; D002648:Child; D002675:Child, Preschool; D005260:Female; D018380:Hematopoietic Stem Cell Transplantation / Q000379:methods; D006801:Humans; D008297:Male; D008334:Mandible / Q000473:pathology; D008437:Maxilla / Q000473:pathology; D008963:Molar / Q000473:pathology*; D009369:Neoplasms / Q000532:radiotherapy / Q000628:therapy*; D012189:Retrospective Studies; D014079:Tooth Eruption, Ectopic / Q000209:etiology*; D014095:Tooth, Impacted / Q000209:etiology
chemical_list: D000970:Antineoplastic Agents