title: Tissue reaction to a triantibiotic paste used for endodontic tissue self-regeneration of nonvital immature permanent teeth.
abstract: BACKGROUND
  The endodontic regenerative procedure (ERP), which is an alternative to calcium hydroxide-induced apexification, involves the use of a triple antibiotic paste (TAP) as a dressing material. The aim of this study was to evaluate the response of rat subcutaneous tissue to implanted polyethylene tubes that were filled with TAP or calcium hydroxide.
  
  
  METHODS
  Thirty rats received 2 individual implants of polyethylene tubes filled with TAP or calcium hydroxide paste (CHP) and another empty tube as a control. Thirty additional rats received 2 individual implants consisting of polyethylene tubes filled with dressing material carriers (macrogol and propylene glycol) and a sham procedure. After 7, 15, 30, 60, and 90 days, 12 animals were euthanized, and the tubes and surrounding tissue were removed and processed for histology by using glycol methacrylate and stained with hematoxylin and eosin. The histological score ranged from 0 to 3 depending on the content of inflammatory cells; the fibrous capsule was considered thin or thick, and necrosis and calcification were recorded as present or absent. The results were analyzed using the Kruskal-Wallis test.
  
  
  RESULTS
  Both dressing materials induced moderate reactions at 7 and 15 days. These reactions were similar to the control (P > .05) and reduced in intensity (to mild) from day 30 onward (P > .05). The carriers did not interfere with the reaction of the dressing materials.
  
  
  CONCLUSIONS
  TAP and CHP were biocompatible over the different experimental periods examined.
authors.affiliation: Department of Endodontics, Araçatuba School of Dentistry, University Estadual Paulista, Sao Paolo, Brazil. joao@foa.unesp.br
authors.forename: João Eduardo
authors.initials: JE
authors.lastname: Gomes-Filho
authors.forename: Paulo Carvalho Tobias
authors.initials: PC
authors.lastname: Duarte
authors.forename: Claudiel Batista
authors.initials: CB
authors.lastname: de Oliveira
authors.forename: Simone
authors.initials: S
authors.lastname: Watanabe
authors.forename: Carolina Simonetti
authors.initials: CS
authors.lastname: Lodi
authors.forename: Luciano Tavares Ângelo
authors.initials: LT
authors.lastname: Cintra
authors.forename: Pedro Felício Estrada
authors.initials: PF
authors.lastname: Bernabé
mesh_terms: D000818:Animals; D000900:Anti-Bacterial Agents / Q000008:administration & dosage / Q000494:pharmacology*; D056624:Apexification / Q000379:methods*; D001672:Biocompatible Materials / Q000494:pharmacology*; D002114:Calcinosis / Q000473:pathology; D002126:Calcium Hydroxide / Q000494:pharmacology; D002939:Ciprofloxacin / Q000008:administration & dosage / Q000494:pharmacology; D004337:Drug Carriers; D004338:Drug Combinations; D005355:Fibrosis; D008214:Lymphocytes / Q000473:pathology; D008264:Macrophages / Q000473:pathology; D008297:Male; D008422:Materials Testing; D008795:Metronidazole / Q000008:administration & dosage / Q000494:pharmacology; D008911:Minocycline / Q000008:administration & dosage / Q000494:pharmacology; D009336:Necrosis; D011092:Polyethylene Glycols; D051381:Rats; D017208:Rats, Wistar; D012038:Regeneration / Q000187:drug effects; D012387:Root Canal Filling Materials / Q000494:pharmacology*; D040521:Subcutaneous Tissue / Q000187:drug effects / Q000473:pathology; D013997:Time Factors; D019553:Tooth, Nonvital / Q000473:pathology
chemical_list: D000900:Anti-Bacterial Agents; D001672:Biocompatible Materials; D004337:Drug Carriers; D004338:Drug Combinations; D012387:Root Canal Filling Materials; D008795:Metronidazole; D011092:Polyethylene Glycols; D002939:Ciprofloxacin; D008911:Minocycline; D002126:Calcium Hydroxide