title: Analysis of the reaction of subcutaneous tissues in rats and the antimicrobial activity of calcium hydroxide paste used in association with different substances.
abstract: The aim of this study was to evaluate the subcutaneous tissue response in rats and the antimicrobial activity of intracanal calcium hydroxide dressings mixed with different substances against E. faecalis. Fifty four rats were divided into three experimental groups according to the vehicle in the calcium hydroxide treatment: 0.4% chlorohexidine in propylene glycol (PG),Casearia sylvestris Sw in PG and calcium hydroxide+PG (control group). The pastes were placed into polyethylene tubes and implanted into the subcutaneous tissue. After 7, 14 and 30 days, the samples were processed and histologically evaluated (hematoxylin and eosin). The tissue surface in contact with the material was analyzed, and the quantitative analysis determined the volume density occupied by the inflammatory infiltrate (giant cells, polymorphonuclear cells and mononuclear cells), fibroblasts, collagen fibers and blood vessels. For the antimicrobial analysis, 20 dentin blocks infected with E. faecalis were treated with calcium hydroxide pastes in different vehicles; 0.4% chlorhexidine in PG, PG, extract from Casearia sylvestris Sw in PG and a positive control (infection and without medication) for 7 days. The efficiency of the pastes was evaluated by the live/dead technique and confocal microscopy. The results showed that 0.4% chlorhexidine induced a higher inflammatory response than the other groups. The Casearia sylvestris Sw extract showed satisfactory results in relation to the intensity of the inflammatory response. In the microbiological test, there were no statistical differences between the evaluated intracanal dressings and the percentage of bacterial viability was between 33 and 42%. The control group showed an 86% viability. Antimicrobial components such as chlorhexidine or Casearia sylvestris Sw did not improve the antimicrobial activity against E. faecalis in comparison to the calcium hydroxide+PG treatment. In addition, the incorporation of chlorhexidine in the calcium hydroxide paste promoted the highest inflammatory response.
authors.affiliation: Department of Dentistry, Endodontics and Dental Materials, Bauru School of Dentistry, University of São Paulo, Bauru, SP, Brazil.
authors.forename: Raquel Zanin
authors.initials: RZ
authors.lastname: Midena
authors.affiliation: Department of Dentistry, Endodontics and Dental Materials, Bauru School of Dentistry, University of São Paulo, Bauru, SP, Brazil.
authors.forename: Roberto Brandão
authors.initials: RB
authors.lastname: Garcia
authors.affiliation: Department of Dentistry, Endodontics and Dental Materials, Bauru School of Dentistry, University of São Paulo, Bauru, SP, Brazil.
authors.forename: Bruno Cavalini
authors.initials: BC
authors.lastname: Cavenago
authors.affiliation: Department of Dentistry, Endodontics and Dental Materials, Bauru School of Dentistry, University of São Paulo, Bauru, SP, Brazil.
authors.forename: Marina Angélica
authors.initials: MA
authors.lastname: Marciano
authors.affiliation: Department of Dentistry, Endodontics and Dental Materials, Bauru School of Dentistry, University of São Paulo, Bauru, SP, Brazil.
authors.forename: Paloma Gagliardi
authors.initials: PG
authors.lastname: Minotti
authors.affiliation: Department of Dentistry, Endodontics and Dental Materials, Bauru School of Dentistry, University of São Paulo, Bauru, SP, Brazil.
authors.forename: Ronald
authors.initials: R
authors.lastname: Ordinola-Zapata
authors.affiliation: Health Sciences Department, University of Sagrado Coração, Bauru, SP, Brazil.
authors.forename: Paulo Henrique
authors.initials: PH
authors.lastname: Weckwerth
authors.affiliation: Department of Dentistry, Endodontics and Dental Materials, Bauru School of Dentistry, University of São Paulo, Bauru, SP, Brazil.
authors.forename: Flaviana Bombarda de
authors.initials: FB
authors.lastname: Andrade
authors.affiliation: Department of Dentistry, Endodontics and Dental Materials, Bauru School of Dentistry, University of São Paulo, Bauru, SP, Brazil.
authors.forename: Marco Antonio Hungaro
authors.initials: MA
authors.lastname: Duarte
mesh_terms: D000818:Animals; D000890:Anti-Infective Agents / Q000737:chemistry / Q000494:pharmacology*; D002126:Calcium Hydroxide / Q000737:chemistry / Q000494:pharmacology*; D037821:Casearia / Q000737:chemistry*; D002417:Cattle; D002478:Cells, Cultured; D002710:Chlorhexidine / Q000737:chemistry / Q000494:pharmacology*; D003094:Collagen / Q000187:drug effects; D013293:Enterococcus faecalis / Q000187:drug effects; D005347:Fibroblasts / Q000187:drug effects; D008422:Materials Testing; D050296:Microbial Viability / Q000187:drug effects; D009824:Ointments; D014677:Pharmaceutical Vehicles / Q000737:chemistry / Q000494:pharmacology; D019946:Propylene Glycol / Q000737:chemistry / Q000494:pharmacology; D017208:Rats, Wistar; D040521:Subcutaneous Tissue / Q000187:drug effects* / Q000473:pathology; D013997:Time Factors
chemical_list: D000890:Anti-Infective Agents; D009824:Ointments; D014677:Pharmaceutical Vehicles; D019946:Propylene Glycol; D003094:Collagen; D002126:Calcium Hydroxide; D002710:Chlorhexidine