title: Comparison of pulp responses following restoration of exposed and non-exposed cavities.
abstract: OBJECTIVE
  The purpose of this study is to compare and contrast differences of pulp responses between non-exposed and exposed cavity preparations in terms of inflammation, frequency of bacterial microleakage, odontoblast and odontoblastoid cell numbers, and tertiary dentine formation.
  
  
  METHODS
  Class V non-exposed cavities (n=161) and exposed cavities (n=161 teeth) were prepared in non-human primate teeth. Cavities were restored with calcium hydroxide [Ca(OH)(2)], resin modified glass ionomer, or resin composite. Following extraction (7-730 days), bacteria were detected with McKays stain and pulp reactions were categorized according to ISO guidelines. Teeth were analyzed histomorphometrically and statistically using analysis of variance tests.
  
  
  RESULTS
  Exposed cavities in comparison with non-exposed cavities were found to have more severe inflammation (p=0.0001), greater quantities of tertiary dentine (p=0.0001), and an increased frequency of bacterial microleakage (p=0.0034). The density of odontoblastoid cells beneath pulp exposed tertiary dentine was found to be 47.8% of odontoblast cell density beneath non-exposed dentine (p=0.0001).
  
  
  CONCLUSIONS
  The restoration of exposed cavity preparations is associated with more traumatic pulp injury and repair responses. Consequently, efforts should be made to minimize iatrogenic dentine removal during cavity preparation and the creation of pulp exposures whenever possible.
authors.affiliation: Oral Biology, Indiana University School of Dentistry, Room 271, 1121 West Michigan Street, Indianapolis, IN 46202-5186, USA. petmurra@iupui.edu
authors.forename: P E
authors.initials: PE
authors.lastname: Murray
authors.forename: A A
authors.initials: AA
authors.lastname: Hafez
authors.forename: L J
authors.initials: LJ
authors.lastname: Windsor
authors.forename: A J
authors.initials: AJ
authors.lastname: Smith
authors.forename: C F
authors.initials: CF
authors.lastname: Cox
mesh_terms: D000704:Analysis of Variance; D000818:Animals; D001419:Bacteria / Q000302:isolation & purification; D002126:Calcium Hydroxide / Q000737:chemistry; D002452:Cell Count; D016009:Chi-Square Distribution; D004396:Coloring Agents; D003188:Composite Resins / Q000737:chemistry; D003736:Dental Cavity Lining; D003737:Dental Cavity Preparation / Q000009:adverse effects / Q000379:methods*; D003763:Dental Leakage / Q000382:microbiology; D003782:Dental Pulp / Q000382:microbiology / Q000473:pathology / Q000503:physiopathology*; D003785:Dental Pulp Capping; D003789:Dental Pulp Exposure / Q000209:etiology / Q000503:physiopathology* / Q000628:therapy; D003793:Dental Restoration, Permanent; D003804:Dentin / Q000382:microbiology / Q000473:pathology; D003809:Dentin, Secondary / Q000473:pathology; D005456:Fluorescent Dyes; D005899:Glass Ionomer Cements / Q000737:chemistry; D008253:Macaca mulatta; D015999:Multivariate Analysis; D009504:Neutrophils / Q000473:pathology; D009804:Odontoblasts / Q000473:pathology; D011671:Pulpitis / Q000209:etiology / Q000473:pathology; D019279:Resin Cements / Q000737:chemistry
chemical_list: D004396:Coloring Agents; D003188:Composite Resins; D005456:Fluorescent Dyes; D005899:Glass Ionomer Cements; D019279:Resin Cements; D002126:Calcium Hydroxide