title: Connective tissue responses to calcium hydroxide-based root canal medicaments.
abstract: OBJECTIVE
  The objective of the present study was to evaluate the tissue inflammatory response induced by calcium hydroxide pastes, with or without paramonochlorophenol and camphor.
  
  
  METHODS
  Isogenic BALB/c mice were inoculated into the subcutaneous tissue with either 0.1 mL of a suspension of Calen, Calen with camphorated paramonochlorophenol, Calen with paramonochlorophenol, Calasept paste or phosphate-buffered saline (control). After 6, 12 and 24 h and 2, 3, 5, 7 and 15 days, three animals in each group were sacrificed and the excised lesions processed for histopathological evaluation of the inflammatory response. Events monitored and graded included the assessment of vascular congestion, oedema, haemorrhage, inflammatory infiltrate, necrosis and tissue repair.
  
  
  RESULTS
  The pastes induced an inflammatory response at every observation period, although the intensity, duration and extension of inflammation varied. Calen paste always produced an initial short-term inflammatory response whilst the other pastes produced extended reactions. All pastes allowed repair to take place by the end of the experimental period, although the speed of this process varied between the materials. Calen presented the best biocompatibility; the phenolic compound caused greater tissue response, which was even more severe in the absence of camphor. Calasept paste was damaging and the repair process slower.
  
  
  CONCLUSIONS
  All calcium hydroxide formulations caused an inflammatory response. The severity and longevity of the responses varied between pastes as a result of the various antiseptic agents. Although irritating, repair was apparent with all formulations.
authors.affiliation: Department of Pediatric Dentistry, Ribeirão Preto Dental School, USP, Brazil.
authors.forename: P
authors.initials: P
authors.lastname: Nelson Filho
authors.forename: L A
authors.initials: LA
authors.lastname: Silva
authors.forename: M R
authors.initials: MR
authors.lastname: Leonardo
authors.forename: L S
authors.initials: LS
authors.lastname: Utrilla
authors.forename: F
authors.initials: F
authors.lastname: Figueiredo
mesh_terms: D000818:Animals; D000891:Anti-Infective Agents, Local / Q000633:toxicity*; D002126:Calcium Hydroxide / Q000737:chemistry / Q000633:toxicity*; D002164:Camphor / Q000633:toxicity*; D002733:Chlorophenols / Q000633:toxicity*; D003238:Connective Tissue / Q000187:drug effects; D004338:Drug Combinations; D005260:Female; D007249:Inflammation / Q000209:etiology; D051379:Mice; D008807:Mice, Inbred BALB C; D009824:Ointments; D014677:Pharmaceutical Vehicles; D012388:Root Canal Irrigants / Q000737:chemistry / Q000633:toxicity*
chemical_list: D000891:Anti-Infective Agents, Local; D002733:Chlorophenols; D004338:Drug Combinations; D009824:Ointments; D014677:Pharmaceutical Vehicles; D012388:Root Canal Irrigants; D002164:Camphor; C029804:camphorated parachlorophenol; D002126:Calcium Hydroxide