title: Atomic force microscopy visualization of injuries in Enterococcus faecalis surface caused by Er,Cr:YSGG and diode lasers.
abstract: OBJECTIVE
  To visualize by atomic force microscopy the alterations induced on Enterococcus. faecalis surface after treatment with 2 types of laser: Erbium chromium:yttrium-scandium-gallium-garnet (Er,Cr:YSGG) laser and Diode laser.
  
  
  METHODS
  Bacterial suspensions from overnight cultures of E. faecalis were irradiated during 30 seconds with the laser-lights at 1 W and 2 W of power, leaving one untreated sample as control. Surface alterations on treated E. faecalis were visualized by atomic force microscopy (AFM) and its surface roughness determined.
  
  
  RESULTS
  AFM imaging showed that at high potency of laser both cell morphology and surface roughness resulted altered, and that several cell lysis signs were easily visualized. Surface roughness clearly increase after the treatment with Er,Cr:YSGG at 2W of power, while the other treatments gave similar values of surface roughness. The effect of lasers on bacterial surfaces visualized by AFM revealed drastic alterations.
  
  
  CONCLUSIONS
  AFM is a good tool to evaluate surface injuries after laser treatment; and could constitute a measure of antimicrobial effect that can complete data obtained by determination of microbial viability.
authors.affiliation: Department of Dentistry, University of Barcelona, Feixa Llarga s/n, 08907 L'Hospitalet del Llobregat, Barcelona, Spain, joseparnabat@ub.edu.
authors.forename: Lidia
authors.initials: L
authors.lastname: López-Jiménez
authors.forename: Josep
authors.initials: J
authors.lastname: Arnabat-Domínguez
authors.forename: Miguel
authors.initials: M
authors.lastname: Viñas
authors.forename: Teresa
authors.initials: T
authors.lastname: Vinuesa
mesh_terms: D056226:Bacterial Structures / Q000528:radiation effects; D013293:Enterococcus faecalis / Q000528:radiation effects*; D054023:Lasers, Semiconductor; D053844:Lasers, Solid-State; D018625:Microscopy, Atomic Force