title: Fractal analysis of mandibular bony healing after orthognathic surgery.
abstract: OBJECTIVE
  We evaluated the radiographic changes to the operational sites after orthognathic surgery by using fractal analysis.
  
  
  METHODS
  Panoramic radiographs from 35 patients who underwent orthognathic surgery on the mandible without any complications during the osseous healing process were selected. The radiographs taken before the operation (stage 0) and 1 or 2 days (stage 1), 1 month (stage 2), 6 months (stage 3), and 12 months (stage 4) after the operation were digitized at 600 dpi with 256 gray levels. The fractal dimension was calculated by means of a tile-counting method in the region of interest centered on the operational site and was statistically analyzed according to its stages.
  
  
  RESULTS
  The fractal dimension was decreased immediately after the operation and increased gradually according to the time lapse (P <.05). The fractal dimension in the region of interest 12 months postoperatively was similar to that preoperatively.
  
  
  CONCLUSIONS
  This result suggests that fractal dimension can be used to evaluate the bony healing process after orthognathic surgery.
authors.affiliation: Department of Oral and Maxillofacial Radiology, College of Dentistry, Seoul National University, Korea.
authors.forename: Min-Suk
authors.initials: MS
authors.lastname: Heo
authors.forename: Kwan-Soo
authors.initials: KS
authors.lastname: Park
authors.forename: Sam-Sun
authors.initials: SS
authors.lastname: Lee
authors.forename: Soon-Chul
authors.initials: SC
authors.lastname: Choi
authors.forename: Jai-Young
authors.initials: JY
authors.lastname: Koak
authors.forename: Seong-Joo
authors.initials: SJ
authors.lastname: Heo
authors.forename: Chong-Hyun
authors.initials: CH
authors.lastname: Han
authors.forename: Jong-Dae
authors.initials: JD
authors.lastname: Kim
mesh_terms: D000328:Adult; D001861:Bone Regeneration; D001863:Bone Screws; D005260:Female; D017709:Fractals; D006801:Humans; D019248:Jaw Fixation Techniques / Q000295:instrumentation; D008297:Male; D008334:Mandible / Q000002:abnormalities / Q000000981:diagnostic imaging / Q000503:physiopathology / Q000601:surgery*; D019647:Oral Surgical Procedures; D010027:Osteotomy; D011378:Prognathism / Q000601:surgery*; D019252:Radiography, Dental, Digital; D011862:Radiography, Panoramic; D014945:Wound Healing