title: Evaluation of apical surface roughness after root resection: a scanning electron microscopic study.
abstract: OBJECTIVE
  The objective of this study was to compare, by scanning electron microscopy, the smoothness of the resected apical root surface after preparation with high-speed #699 bur, #699 bur plus Shofu finishing and Zekrya bur, and with an erbium:YAG laser.
  
  
  METHODS
  Thirty-nine extracted human premolars were instrumented and obturated and their root apices were resected. The roots were divided into 4 groups according to the root resection method. The teeth were dried, metallized, and analyzed at x400 by scanning electron microscopy. Scores ranging from 0 to 3 were attributed to surface smoothness. The data were analyzed by the Kruskal-Wallis test for overall comparison, and by Dunn's test for individual comparisons.
  
  
  RESULTS
  Smoother surfaces were observed for the groups treated with the #699 bur and the #699 bur plus Shofu point finishing, while rougher surfaces were obtained with the laser, which differed significantly from the other 2 methods (P < .05).
  
  
  CONCLUSIONS
  Treatment with the #699 bur plus Shofu finishing yielded better results in terms of surface smoothness, whereas the laser treatment produced more irregular and rougher surfaces after root resection.
authors.affiliation: Sagrado Coração University, Bauru, São Paulo, Brazil. mhungaro@travelnet.com.br
authors.forename: Marco Antonio Hungaro
authors.initials: MA
authors.lastname: Duarte
authors.forename: Rubens
authors.initials: R
authors.lastname: Domingues
authors.forename: Marisa Akemi
authors.initials: MA
authors.lastname: Matsumoto
authors.forename: Luis Eduardo Marques
authors.initials: LE
authors.lastname: Padovan
authors.forename: Milton Carlos
authors.initials: MC
authors.lastname: Kuga
mesh_terms: D001047:Apicoectomy / Q000295:instrumentation*; D001641:Bicuspid / Q000601:surgery*; D003754:Dental High-Speed Equipment; D003804:Dentin / Q000601:surgery / Q000648:ultrastructure; D006801:Humans; D053844:Lasers, Solid-State / Q000627:therapeutic use*; D008855:Microscopy, Electron, Scanning; D018709:Statistics, Nonparametric; D019227:Tooth Apex / Q000601:surgery / Q000648:ultrastructure*