title: Five-minute Apgar score ≤ 5 and Molar Incisor Hypomineralisation (MIH) - a case control study.
abstract: BACKGROUND
  The aetiology of molar incisor hypomineralisation (MIH) is unclear. The asymmetric distribution of MIH in the dentition may indicate that an insult of short duration that affects ameloblasts at a vulnerable stage could be a causative factor. Apgar ≤ 5 at 5 min may indicate asphyxia (hypoxic-ischemic insult) during birth. It was hypnotised that low Apgar score during birth may cause MIH. The present study aimed to examine a possible association between Apgar ≤ 5 at 5 min and the occurrence of MIH.
  
  
  METHODS
  Two study groups were selected for examination. The cases comprised 67 children aged 8-10 years born with Apgar score equal to or below 5 after 5 min. The control group comprised 157 age-matched healthy children. First permanent molars, second primary molars and all permanent incisors were examined in all children. Clinical examination was undertaken by two calibrated examiners and intraoral close-up photographs of the teeth were later evaluated by three calibrated and blinded clinicians. Demarcated opacities, post-eruptive breakdown, atypical restorations and extractions due to MIH, according to the criteria of the European Association of Paediatric Dentistry, were assessed.
  
  
  RESULTS
  The prevalence of MIH did not differ between the two groups. A chi-square test failed to confirm any statistically significant relationship between 5-min Apgar scores and MIH occurrence. In addition, there was no statistically significant relationship between the number of affected first permanent molars in cases and controls.
  
  
  CONCLUSIONS
  There was no association between Apgar ≤ 5 at 5 min and the occurrence of MIH.
authors.affiliation: Department of Biomaterials, Institute of Clinical Dentistry, Faculty of Dentistry, University of Oslo, Oslo, Norway. rivan.sidaly@odont.uio.no.|Department of Biomaterials, Faculty of Dentistry, PO Box 1109, Blindern, N-0317, Oslo, Norway. rivan.sidaly@odont.uio.no.
authors.forename: Rivan
authors.initials: R
authors.lastname: Sidaly
authors.affiliation: Department of Clinical Dentistry, UiT The Arctic University of Norway, Tromsø, Norway.
authors.forename: Andreas
authors.initials: A
authors.lastname: Schmalfuss
authors.affiliation: Department of Paediatric Dentistry and Behavioural Science, Institute of Clinical Dentistry, Faculty of Dentistry, University of Oslo, Oslo, Norway.
authors.forename: Anne B
authors.initials: AB
authors.lastname: Skaare
authors.affiliation: Institute of Oral Biology, Faculty of Dentistry, University of Oslo, Oslo, Norway.
authors.forename: Amer
authors.initials: A
authors.lastname: Sehic
authors.affiliation: Department of Neonatology, Oslo University Hospital, Oslo, Norway.
authors.forename: Tom
authors.initials: T
authors.lastname: Stiris
authors.affiliation: Department of Paediatric Dentistry and Behavioural Science, Institute of Clinical Dentistry, Faculty of Dentistry, University of Oslo, Oslo, Norway.
authors.forename: Ivar
authors.initials: I
authors.lastname: Espelid
mesh_terms: D001034:Apgar Score; D016022:Case-Control Studies; D002648:Child; D003744:Dental Enamel Hypoplasia; D005260:Female; D006801:Humans; D007180:Incisor; D007231:Infant, Newborn; D008297:Male; D008963:Molar; D015995:Prevalence
keywords: Ameloblasts; Apgar score; Asphyxia; Enamel; Molar incisor hypomineralisation