title: Effect of low-level laser therapy on dental root cementum remodeling in rats.
abstract: OBJECTIVE
  To investigate the amount of the cementum layer formed over the rat's dental root surfaces by daily application of low-level laser therapy (LLLT) for 2 weeks.
  
  
  METHODS
  Twelve female Sprague-Dawley (SD) rats were divided into two groups: six rats received daily LLLT (Ga-Al-As, 830 nm), and six rats received no treatment (control). The treatment lasted 2 weeks. In vivo Micro-CT imaging analyzed the root's hard tissue volumetric changes. The cementum thickness was evaluated histologically.
  
  
  RESULTS
  Total cementum thicknesses in the LLLT group increased significantly (p = 0.015) compared to the control group. This significant increase in the cementum thickness, verified histologically, was not detectable during in vivo Micro-CT imaging, which showed no significant difference between the groups regarding the root hard tissues volumetric changes over the 2-week evaluation period.
  
  
  CONCLUSIONS
  Two weeks of daily application of LLLT significantly increased rat's dental root cementum thickness as determined histologically. However, in vivo Micro-CT imaging failed to accurately reveal this cementum growth as it was not possible to differentiate dentinal changes.
authors.affiliation: Medical Sciences Orthodontics Doctoral Program, University of Alberta, Edmonton, AB, Canada.
authors.forename: M
authors.initials: M
authors.lastname: Alsulaimani
authors.forename: M
authors.initials: M
authors.lastname: Doschak
authors.forename: D
authors.initials: D
authors.lastname: Dederich
authors.forename: C
authors.initials: C
authors.lastname: Flores-Mir
mesh_terms: D000818:Animals; D025021:Cementogenesis / Q000528:radiation effects*; D003739:Dental Cementum / Q000033:anatomy & histology / Q000528:radiation effects*; D005260:Female; D007091:Image Processing, Computer-Assisted / Q000379:methods; D054023:Lasers, Semiconductor / Q000627:therapeutic use; D028022:Low-Level Light Therapy / Q000379:methods*; D023421:Models, Animal; D011829:Radiation Dosage; D011897:Random Allocation; D051381:Rats; D017207:Rats, Sprague-Dawley; D013997:Time Factors; D019227:Tooth Apex / Q000033:anatomy & histology / Q000528:radiation effects; D014092:Tooth Root / Q000033:anatomy & histology / Q000528:radiation effects*; D055114:X-Ray Microtomography / Q000379:methods
keywords: cementum; low level laser therapy; rats; root volume