title: Influence of the number of sections on reliability of in vitro microleakage evaluations.
abstract: OBJECTIVE
  To test how the number of sections affects the maximum depth of tracer penetration.
  
  
  METHODS
  This study was simultaneously performed in three different centers. C-shaped Class V cavities were made on 60 human third molars. The cavities were located across the cementum-enamel junction. One restorative system was used: Scotchbond Multi-Purpose and Z100. After restoration, the samples were thermally cycled 3000 times, between 5 and 55 degrees C with a dwell time immersion of 10 seconds. Silver nitrate was used by two centers and basic fuchsin was used by the third. The teeth were longitudinally sectioned with a diamond saw: 5 sections per tooth provided 10 surfaces for evaluation. The penetration of the tracer was recorded on a scale from 0 to 3. The deepest leakage per restoration was identified for comparison with lesser measured values elsewhere in the tooth. The Spearman test was applied to evaluate the relationship between the reference and data from one, two and three sections (i.e. two, four and six measurements). The Kruskal-Wallis test was applied to compare the three centers.
  
  
  RESULTS
  Whatever the study center, the Spearman correlation coefficient (r(s)) increased as a function of the number of sections (S) up to three: Center 1 (1S, 0.47; 2S, 0.68; 3S, 1.0), Center 2 (1S, 0.60; 2S, 0.99; 3S, 0.99), Center 3 (S1, 0.40; 2S, 0.73; 3S, 1.0). No statistically significant difference was found between the three study centers.
authors.affiliation: UFR d'Odontologie de Marseille, Université de la Méditerranée, Aix-Marseille II, 27, Boulevard Jean Moulin, 13 385 Marseille, Cedex 05 France. anne.raskin@wanadoo.fr
authors.forename: Anne
authors.initials: A
authors.lastname: Raskin
authors.forename: Herve
authors.initials: H
authors.lastname: Tassery
authors.forename: William
authors.initials: W
authors.lastname: D'Hoore
authors.forename: Samuel
authors.initials: S
authors.lastname: Gonthier
authors.forename: José
authors.initials: J
authors.lastname: Vreven
authors.forename: Michel
authors.initials: M
authors.lastname: Degrange
authors.forename: Jaques
authors.initials: J
authors.lastname: Déjou
mesh_terms: D003188:Composite Resins / Q000737:chemistry; D003737:Dental Cavity Preparation / Q000145:classification; D003763:Dental Leakage / Q000145:classification / Q000175:diagnosis*; D003793:Dental Restoration, Permanent; D006801:Humans; D008867:Microtomy / Q000379:methods*; D015203:Reproducibility of Results; D019279:Resin Cements / Q000737:chemistry; D012394:Rosaniline Dyes; D012822:Silicon Dioxide; D016622:Silver Staining; D018709:Statistics, Nonparametric; D013499:Surface Properties; D019237:Tooth Cervix / Q000473:pathology; D015040:Zirconium
chemical_list: D003188:Composite Resins; D019279:Resin Cements; D012394:Rosaniline Dyes; C084018:Scotchbond Multi-Purpose; C083568:Z100 composite resin; C025485:basic fuchsin; D012822:Silicon Dioxide; D015040:Zirconium