title: Microleakage of stainless steel crowns placed on intact and extensively destroyed primary first molars: an in vitro study.
abstract: OBJECTIVE
  The purpose of this investigation was to evaluate the effect of residual tooth structure on the microleakage of stainless steel crowns cemented with glass ionomer on primary maxillary and mandibular first molars.
  
  
  METHODS
  Thirty extracted primary molars were divided  into 2 groups: group 1 included intact teeth; and group 2 included extensively carious samples. Each tooth received standard preparation, and each crown was luted with G-CEM on its specific specimen. Teeth were loaded vertically and transferred to distilled water. After thermocycling and immersing  in methylene blue solution, the teeth were sectioned and examined microscopically for microleakage. Data were analyzed using Mann-Whitney U and Wilcoxon signed-rank tests.
  
  
  RESULTS
  All specimens (intact and damaged teeth) had microleakage, although most of these presented only minimum  microleakage. No statistically significant differences were found in the microleakage of sound and extensively carious teeth on either the buccal (P=.62) or lingual (P=.65) side. Buccal (P=.73) and lingual (P=.63) surfaces showed similar microleakage scores in primary maxillary and mandibular  molars.
  
  
  CONCLUSIONS
  There was no significant difference in the microleakage of sound or extensively carious teeth and primary maxillary or mandibular first molars.
authors.affiliation: Department of Oral Pathology, Dental School, Tehran University of Medical Sciences, Teharn, Iran.
authors.forename: Bahman
authors.initials: B
authors.lastname: Seraj
authors.forename: Mahdi
authors.initials: M
authors.lastname: Shahrabi
authors.forename: Pouria
authors.initials: P
authors.lastname: Motahari
authors.forename: Rahil
authors.initials: R
authors.lastname: Ahmadi
authors.forename: Sara
authors.initials: S
authors.lastname: Ghadimi
authors.forename: Shahram
authors.initials: S
authors.lastname: Mosharafian
authors.forename: Kaveh
authors.initials: K
authors.lastname: Mohammadi
authors.forename: Mohammad
authors.initials: M
authors.lastname: Javad Kharazifard
mesh_terms: D002484:Cementation / Q000379:methods; D004396:Coloring Agents; D003442:Crowns; D003722:Dental Alloys / Q000737:chemistry*; D003731:Dental Caries / Q000473:pathology*; D003763:Dental Leakage / Q000145:classification*; D005899:Glass Ionomer Cements / Q000737:chemistry; D006801:Humans; D008422:Materials Testing; D008751:Methylene Blue; D008963:Molar / Q000473:pathology*; D013193:Stainless Steel / Q000737:chemistry*; D013696:Temperature; D013997:Time Factors; D019231:Tooth Preparation, Prosthodontic / Q000379:methods; D014094:Tooth, Deciduous / Q000473:pathology*
chemical_list: D004396:Coloring Agents; D003722:Dental Alloys; D005899:Glass Ionomer Cements; D013193:Stainless Steel; D008751:Methylene Blue