title: Fractal properties of the trabecular pattern of the mandible in chronic renal failure.
abstract: OBJECTIVE
  The purpose of this study was to evaluate fractal analysis as a tool to quantitatively determine the mandibular trabecular bone changes in patients with chronic renal failure (CRF).
  
  
  METHODS
  In the present study, fractal analysis was performed using ImageJ (National Institutes of Health, Bethesda, MD) program with box-counting method over panoramic radiographs of 25 patients (14 females and 11 males) with CRF and 26 healthy individuals (14 females and 12 males) as a control group. The fractal dimension (FD) values of the patients and healthy individuals were compared. In addition, average biochemical parameters [parathyroid hormone (PTH), calcium (Ca), phosphorus (P), product of Ca and P levels (CaxP), alkaline phosphatase (ALP), vitamin D] of the patients with CRF, as measured during the 3 months before the panoramic radiographs, were compared with FD values.
  
  
  RESULTS
  According to the results, FD values of the patients with CRF were found to be statistically lower than the control group (p < 0.05). The average PTH levels of the patients with CRF were 416.16 ± 310.3 pg ml(-1); average Ca levels were 8.94 ± 1.2 mg dl(-1); average P levels were 5.76 ± 1.7 mg dl(-1); average CaxP values were 51.12 ± 15.03; average ALP levels were 83.44 ± 36.8 U l(-1); and the average vitamin D values were 19.43 ± 9.7 ng ml(-1). In addition, there was no significant correlation between FD values and the biochemical parameters of the patients, and there was no correlation between age, gender and FD.
  
  
  CONCLUSIONS
  The FD values of the patients with CRF were lower than those of the controls. This finding suggests that FD analysis might be a promising simple and cost-effective tool for evaluating trabecular bone structure.
authors.affiliation: 1 Department of Dentomaxillofacial Radiology, Faculty of Dentistry, Recep Tayyip Erdogan University, Rize, Turkey.
authors.forename: Ismail
authors.initials: I
authors.lastname: Gumussoy
authors.affiliation: 2 Department of Dentomaxillofacial Radiology, Faculty of Dentistry, Ataturk University, Erzurum, Turkey.
authors.forename: Ozkan
authors.initials: O
authors.lastname: Miloglu
authors.affiliation: 3 Department of Nephrology, Faculty of Medicine, Ataturk University, Erzurum, Turkey.
authors.forename: Erdem
authors.initials: E
authors.lastname: Cankaya
authors.affiliation: 4 Department of Dentomaxillofacial Radiology, Faculty of Dentistry, Osmangazi University, Eskişehir, Turkey.
authors.forename: Ibrahim S
authors.initials: IS
authors.lastname: Bayrakdar
mesh_terms: D000328:Adult; D000071556:Cancellous Bone / Q000000981:diagnostic imaging*; D005260:Female; D006801:Humans; D007676:Kidney Failure, Chronic / Q000150:complications*; D008297:Male; D008334:Mandible / Q000000981:diagnostic imaging*; D008875:Middle Aged; D011862:Radiography, Panoramic; D012887:Skull Fractures / Q000000981:diagnostic imaging* / Q000209:etiology; D055815:Young Adult
keywords: chronic renal failure; fractals; panoramic radiography; trabecular bone