title: Effect of rotary instrumentation and of the association of calcium hydroxide and chlorhexidine on the antisepsis of the root canal system in dogs.
abstract: This study aimed at evaluating the antisepsis of the root canal system (RCS) and periapical region (PR) provided by rotary instrumentation associated with chlorhexidine + calcium hydroxide as intracanal medicament. Chronic periapical lesions were induced in 26 pre-molar roots in two dogs. After microbiological sampling, automatic instrumentation using the Profile system and irrigation with 5.25% sodium hypochlorite solution, with a final rinse of 14.3% EDTA followed by profuse irrigation with physiological saline were carried out in 18 root canals. After drying the canals, a paste based on calcium hydroxide associated with a 2% chlorhexidine digluconate solution was placed inside them. After 21 days, the medication was removed, leaving the root canals empty and coronally sealed. After 96 hours, a final microbiological sample was obtained, followed by histomicrobiological processing by the Brown & Brenn method. Eight untreated root canals represented the control group (C-G). Based on the Mann-Whitney test at a confidence level of 5% (p < 0.05), the procedures of antisepsis used offered significant efficacy (p < 0.05) resulting in 100.0% of the canals free of microorganisms. In the C-G, an elevated incidence of various microbial morphotypes was confirmed in all sites of the RCS, with the presence of microbial colonies in the periapical region. In contrast, the experimental group showed a similar pattern of infection in the RCS, although less intense and a reduced level of periapical infection (p < 0.05). It was concluded that adequate instrumentation followed by the application of calcium hydroxide + chlorhexidine offered significant elimination of microorganisms.
authors.affiliation: Federal University of the Valleys of Jequitinhonha and Mucuri.
authors.forename: Janir Alves
authors.initials: JA
authors.lastname: Soares
authors.forename: Mario Roberto
authors.initials: MR
authors.lastname: Leonardo
authors.forename: Léa Assed Bezerra
authors.initials: LA
authors.lastname: da Silva
authors.forename: Mario
authors.initials: M
authors.lastname: Tanomaru Filho
authors.forename: Izabel Yoko
authors.initials: IY
authors.lastname: Ito
mesh_terms: D000818:Animals; D000891:Anti-Infective Agents, Local / Q000008:administration & dosage*; D001843:Bone Cements / Q000494:pharmacology*; D002126:Calcium Hydroxide / Q000008:administration & dosage*; D002710:Chlorhexidine / Q000008:administration & dosage*; D003786:Dental Pulp Cavity / Q000382:microbiology*; D004285:Dogs; D004338:Drug Combinations; D023421:Models, Animal; D018915:Root Canal Preparation / Q000295:instrumentation*
chemical_list: D000891:Anti-Infective Agents, Local; D001843:Bone Cements; D004338:Drug Combinations; D002126:Calcium Hydroxide; D002710:Chlorhexidine