title: Do prenatal and postnatal hypothyroidism affect the craniofacial structure?: An experimental study.
abstract: OBJECTIVE
  To investigate the effect of experimental prenatal and postnatal hypothyroidism (HT) on the craniofacial structure in rats.
  
  
  METHODS
  Female Wistar albino rats were mated with males for fertilization. Pregnant rats were divided into three groups. Group 1 (methimazole [MMI]-induced prenatal hypothyroidism group) mother rats were given MMI water during and after pregnancy. Group 2 (MMI-induced postnatal hypothyroidism group) mother rats were given MMI water after pregnancy. After the breast-feeding period, group 1 and 2 rat pups received the same water as their lactating mothers drank. Group 3 (control group) pregnant rats and rat pups were given normal tap water. When the rat pups were 90 days of age, lateral cephalometric and posteroanterior films were taken under anesthesia.
  
  
  RESULTS
  Posteroanterior radiographs revealed that palatal, cranial, bizygomatic arch, and bigonial width measurements were significantly shorter in prenatal HT and postnatal HT groups compared to the control group (P < .001). Intragroup comparisons in lateral cephalometric radiographs showed that, nearly all of the comparisons were statistically significant (P < .05), with the exception of the Co-Gn, E-Pg/S-Gn measurements between the prenatal and postnatal HT groups.
  
  
  CONCLUSIONS
  Sagittal and transverse measurements showed that untreated HT has detrimental effects on the growth of the maxilla and mandible.
authors.affiliation: a  Assistant Professor, Adnan Menderes University, Faculty of Dentistry, Department of Orthodontics, Aydın, Turkey.
authors.forename: Mine
authors.initials: M
authors.lastname: Gecgelen Cesur
authors.affiliation: b  Associate Professor, Adnan Menderes University, Faculty of Medicine, Department of Physiology, Aydın, Turkey.
authors.forename: Gokhan
authors.initials: G
authors.lastname: Cesur
authors.affiliation: c  Research Assistant, Adnan Menderes University, Faculty of Dentistry, Department of Orthodontics, Aydın, Turkey.
authors.forename: Mert
authors.initials: M
authors.lastname: Ogrenim
authors.affiliation: d  Research Assistant, Yıldırım Beyazıt University, Faculty of Medicine, Department of Biostatistics, Ankara, Turkey.
authors.forename: Afra
authors.initials: A
authors.lastname: Alkan
mesh_terms: D000818:Animals; D002508:Cephalometry; D005260:Female; D007037:Hypothyroidism / Q000150:complications*; D007774:Lactation; D008297:Male; D008334:Mandible / Q000254:growth & development / Q000473:pathology*; D008437:Maxilla / Q000254:growth & development / Q000473:pathology*; D008713:Methimazole; D011247:Pregnancy; D051381:Rats; D017208:Rats, Wistar
chemical_list: D008713:Methimazole
keywords: Craniofacial structure; Hypothyroidism