title: Relationship between files that bind at the apical foramen and foramen openings in maxillary central incisors--a SEM study.
abstract: Considering that instrumentation of the apical foramen has been suggested for root canal infection control, this study analyzed the relationship between the files that bind at the apical foramen and the foraminal openings in 50 maxillary central incisors. After preparation of the pulp chamber, access to the canal was obtained with #1 and 2 LA Axxess and K-files with tip cut were inserted up to the apical foramen until binding was felt. The files were fixed with methyl cyanoacrylate and the tooth-file sets were cross-sectioned 10 mm short of the apex. Scanning electron microscopic analysis was carried out and files and foraminal areas were measured using Image Tool software. Statistically significant difference (p<0.0001) was found between files and the apical foraminal areas. The mean foraminal area was 3.8 times larger than the mean file area. The results of this study suggest that it would require 4 files of greater size beyond the one that bound to the foramen in order to allow a better relationship between files and apical openings of maxillary central incisors.
authors.affiliation: Graduate Program, Dental School, University of Ribeirão Preto, Ribeirão Preto, SP, Brazil. ronaldosouza.endo@gmail.com
authors.forename: Ronaldo Araújo
authors.initials: RA
authors.lastname: Souza
authors.forename: Yara T Corrêa Silva
authors.initials: YT
authors.lastname: Sousa
authors.forename: José Antônio Poli
authors.initials: JA
authors.lastname: de Figueiredo
authors.forename: João Da Costa Pinto
authors.initials: Jda C
authors.lastname: Dantas
authors.forename: Suely
authors.initials: S
authors.lastname: Colombo
authors.forename: Jesus Djalma
authors.initials: JD
authors.lastname: Pécora
mesh_terms: D003487:Cyanoacrylates / Q000737:chemistry; D003786:Dental Pulp Cavity / Q000648:ultrastructure*; D004867:Equipment Design; D006801:Humans; D007180:Incisor / Q000648:ultrastructure*; D008437:Maxilla / Q000648:ultrastructure*; D008855:Microscopy, Electron, Scanning; D016613:Plastic Embedding; D016300:Radiography, Bitewing; D018915:Root Canal Preparation / Q000295:instrumentation* / Q000379:methods; D013499:Surface Properties; D016707:Tissue Fixation; D019227:Tooth Apex / Q000648:ultrastructure*
chemical_list: D003487:Cyanoacrylates; C008424:methyl 2-cyanoacrylate