title: Aetiology of Molar-Incisor Hypomineralisation: A systematic review.
abstract: OBJECTIVE
  This was to review and assess the studies on aetiology of Molar-Incisor Hypomineralisation (MIH) or, as a proxy, of demarcated opacities in permanent first molars and to consider the potential factors involved with findings obtained in animal experiments.
  
  
  METHODS
  A systematic search by Medline online database was performed. Abstracts behind appropriate titles were studied and finally the full articles were evaluated for their strength of evidence in the aetiology of MIH.
  
  
  RESULTS
  From a total of 1,142 articles 28 were identified and selected for review. The selected papers covered medical problems in prenatal, perinatal and postnatal period, medication of the child during the first years of life, and exposure to fluoride or environmental toxicants (dioxins and PCBs) in the early childhood. Based on the assessment of the articles it was still not possible to specifically name those factors causing MIH although correlations between several potential factors and MIH were presented. Among the factors suggested and found to cause enamel defects in animal experiments were: high fever, hypoxia, hypocalcaemia, exposure to antibiotics (amoxicillin, a macrolide), and dioxins.
  
  
  CONCLUSIONS
  Despite increased knowledge on the aetiology of MIH insufficient evidence to verify the causative factors exists. Further studies, especially prospective ones, are needed to improve the level and strength of evidence of the role of the present putative factors and to reveal new factors that may be involved. Any combined effect of several factors should be taken into account. Experimental dose/response studies and research on the molecular mechanisms causing the abnormal function of the ameloblasts are also necessary to deepen our knowledge of MIH.
authors.affiliation: Dept. Pediatric and Preventive Dentistry, Institute of Dentistry, FI-00014 University of Helsinki, Helsinki, Finland. Satu.Alaluusua@helsinki.fi
authors.forename: S
authors.initials: S
authors.lastname: Alaluusua
mesh_terms: D000566:Amelogenesis / Q000502:physiology; D000818:Animals; D000900:Anti-Bacterial Agents / Q000009:adverse effects; D001942:Breast Feeding / Q000009:adverse effects; D002648:Child; D002675:Child, Preschool; D003744:Dental Enamel Hypoplasia / Q000209:etiology*; D004785:Environmental Pollutants / Q000009:adverse effects; D005334:Fever / Q000150:complications; D005459:Fluorides / Q000009:adverse effects; D006801:Humans; D006996:Hypocalcemia / Q000150:complications; D000860:Hypoxia / Q000150:complications; D007223:Infant
chemical_list: D000900:Anti-Bacterial Agents; D004785:Environmental Pollutants; D005459:Fluorides
references.citation: J Dent Child (Chic). 2003 Sep-Dec;70(3):215-20
references.pmid: 14998204
references.citation: Caries Res. 2001 Sep-Oct;35(5):390-1
references.pmid: 11641576
references.citation: J Dent Res. 1996 Oct;75(10):1753-60
references.pmid: 8955670
references.citation: Pediatr Dent. 1996 Sep-Oct;18(5):379-84
references.pmid: 8897530
references.citation: Anat Rec. 1994 Aug;239(4):379-95
references.pmid: 7978362
references.citation: Eur Arch Paediatr Dent. 2008 Dec;9(4):224-7
references.pmid: 19054476
references.citation: Eur J Paediatr Dent. 2003 Sep;4(3):133-7
references.pmid: 14529334
references.citation: Adv Dent Res. 1989 Sep;3(2):188-98
references.pmid: 2640430
references.citation: J Histochem Cytochem. 2000 Aug;48(8):1043-58
references.pmid: 10898799
references.citation: Int J Paediatr Dent. 2009 May;19(3):176-85
references.pmid: 19016928
references.citation: Br Dent J. 2004 May 22;196(10):634-8; discussion 625
references.pmid: 15153976
references.citation: Int J Paediatr Dent. 2008 May;18(3):155-62
references.pmid: 18384347
references.citation: N Z Dent J. 1989 Jan;85(379):2-8
references.pmid: 2783769
references.citation: Eur J Paediatr Dent. 2002 Mar;3(1):9-13
references.pmid: 12871011
references.citation: Caries Res. 1995;29(1):20-5
references.pmid: 7867046
references.citation: Arch Pediatr Adolesc Med. 2005 Oct;159(10):943-8
references.pmid: 16203939
references.citation: Int Dent J. 2003 Aug;53(4):243-8
references.pmid: 12953893
references.citation: Environ Toxicol Pharmacol. 1996 May 15;1(3):193-7
references.pmid: 21781681
references.citation: Int Dent J. 1992 Dec;42(6):411-26
references.pmid: 1286924
references.citation: Arch Oral Biol. 2005 Feb;50(2):185-8
references.pmid: 15721149
references.citation: Caries Res. 2001 Jan-Feb;35(1):36-40
references.pmid: 11125194
references.citation: Eur J Paediatr Dent. 2008 Sep;9(3):139-44
references.pmid: 18844443
references.citation: J Vet Med Sci. 2003 Sep;65(9):985-8
references.pmid: 14532690
references.citation: J Dent Res. 2009 Feb;88(2):132-6
references.pmid: 19278983
references.citation: ASDC J Dent Child. 1995 Jul-Aug;62(4):266-9
references.pmid: 7593885
references.citation: Community Dent Health. 1990 Sep;7(3):229-36
references.pmid: 2076499
references.citation: Caries Res. 1997;31(4):259-67
references.pmid: 9197931
references.citation: J Dent Res. 2004 Feb;83(2):139-44
references.pmid: 14742652
references.citation: Int J Paediatr Dent. 2009 Mar;19(2):73-83
references.pmid: 19250392
references.citation: J Oral Pathol Med. 2000 Sep;29(8):403-9
references.pmid: 10972349
references.citation: J Hum Evol. 2006 Mar;50(3):329-46
references.pmid: 16300817
references.citation: Swed Dent J. 2007;31(4):155-64
references.pmid: 18220218
references.citation: Eur J Oral Sci. 1996 Oct-Dec;104(5-6):493-7
references.pmid: 9021315
references.citation: Scand J Dent Res. 1994 Oct;102(5):249-53
references.pmid: 7817148
references.citation: Caries Res. 1998;32(6):405-11
references.pmid: 9745112
references.citation: Caries Res. 2000 Nov-Dec;34(6):469-73
references.pmid: 11093020
references.citation: Arch Oral Biol. 2006 Jun;51(6):464-70
references.pmid: 16426566
references.citation: Int Dent J. 2006 Dec;56(6):323-31
references.pmid: 17243464
references.citation: Arch Oral Biol. 2001 Mar;46(3):239-47
references.pmid: 11165570
references.citation: Odontol Revy. 1954;5(1):7-26
references.pmid: 13176861
references.citation: Chemosphere. 2007 Apr;67(9):S350-4
references.pmid: 17250867
references.citation: N Z Dent J. 2005 Jun;101(2):35-43
references.pmid: 16011308
references.citation: Environ Health Perspect. 2004 Sep;112(13):1313-8
references.pmid: 15345345
references.citation: Eur Arch Paediatr Dent. 2008 Dec;9(4):207-17
references.pmid: 19054474
references.citation: Community Dent Oral Epidemiol. 1987 Oct;15(5):279-85
references.pmid: 3477361