title: In vivo bone regenerative effect of low-intensity pulsed ultrasound in rat calvarial defects.
abstract: OBJECTIVE
  Low-intensity pulsed ultrasound (LIPUS) is a biophysical intervention in a bone repair process. However, neither the healing events of the flat bones of the skull using LIPUS nor the optimal stimulation settings are fully understood. The aim of this study was to evaluate the bone regenerative effect of LIPUS in rat calvarial flat bone defects by using in vivo microfocus computerized tomography (micro-CT).
  
  
  METHODS
  The calvarium was exposed, and noncritical-sized 2.7-mm defects were prepared. LIPUS (1.6 MHz, repeating 1.0-kHz pulsation, and 30-mW/cm(2) intensity) was applied for 20 minutes daily. Bone regeneration was evaluated by image analysis using micro-CT and histologic examination.
  
  
  RESULTS
  Within 2 weeks, LIPUS-treated rats demonstrated 7.0% reossification of the original surgical defect, whereas control rats demonstrated 3.6%. At 3 and 4 weeks, a significant difference in the reossification ratio was observed (12.0% vs. 5.8% and 18.1% vs. 9.8%, respectively; P < .05).
  
  
  CONCLUSIONS
  LIPUS accelerated bone regeneration of noncritical rat calvarial defects as confirmed by micro-CT.
authors.affiliation: Division of Applied Oral Sciences, Nihon University School of Dentistry, Tokyo, Japan.
authors.forename: Akira
authors.initials: A
authors.lastname: Hasuike
authors.forename: Shuichi
authors.initials: S
authors.lastname: Sato
authors.forename: Asami
authors.initials: A
authors.lastname: Udagawa
authors.forename: Kazunari
authors.initials: K
authors.lastname: Ando
authors.forename: Yoshinori
authors.initials: Y
authors.lastname: Arai
authors.forename: Koichi
authors.initials: K
authors.lastname: Ito
mesh_terms: D000818:Animals; D001861:Bone Regeneration; D008297:Male; D051381:Rats; D011916:Rats, Inbred F344; D012886:Skull / Q000000981:diagnostic imaging / Q000601:surgery; D014464:Ultrasonic Therapy / Q000379:methods; D055114:X-Ray Microtomography