title: Evaluation of root resorption following rapid maxillary expansion using cone-beam computed tomography.
abstract: OBJECTIVE
  To evaluate the root resorption after rapid maxillary expansion (RME) via cone-beam computed tomography (CBCT).
  
  
  METHODS
  Records of 25 patients who had undergone RME with tooth-borne banded expander were obtained from the archive of the orthodontic department. CBCT data were reconstructed with surface and volume rendering, and the volumetric images were manipulated to display the root surfaces from various orientations. On these three-dimensional images, permanent first molars and first and second premolars were segmented, and their roots were isolated. Volumes of roots were calculated. The difference between pre-expansion and postexpansion root volumes was statistically evaluated with a paired-samples t-test. Also, the percentage of root volume loss was calculated for each root and statistically compared with each other with one-way analysis of variance at the P < .05 level.
  
  
  RESULTS
  The difference between the pre-expansion and postexpansion root volumes was statistically significant for all roots investigated. Maximum volume decrease was observed for the mesiobuccal root of first molar teeth (18.60 mm(3)). It was determined that the distobuccal root of first molar teeth was less affected from the expansion procedure (9.47 mm(3)). No statistically significant difference was found for the percentage of root volume loss.
  
  
  CONCLUSIONS
  Following RME treatment, significant root volume loss was observed for all investigated posterior teeth. However, the percentage of volume loss was not statistically different among roots.
authors.affiliation: Department of Orthodontics, Faculty of Dentistry, Kocaeli University, Kocaeli, Turkey.
authors.forename: Asli
authors.initials: A
authors.lastname: Baysal
authors.forename: Irfan
authors.initials: I
authors.lastname: Karadede
authors.forename: Seyit
authors.initials: S
authors.lastname: Hekimoglu
authors.forename: Faruk
authors.initials: F
authors.lastname: Ucar
authors.forename: Törün
authors.initials: T
authors.lastname: Ozer
authors.forename: Ilknur
authors.initials: I
authors.lastname: Veli
authors.forename: Tancan
authors.initials: T
authors.lastname: Uysal
mesh_terms: D000704:Analysis of Variance; D002648:Child; D054893:Cone-Beam Computed Tomography; D003799:Dental Stress Analysis; D005260:Female; D006801:Humans; D021621:Imaging, Three-Dimensional; D008297:Male; D010155:Palatal Expansion Technique / Q000009:adverse effects*; D012189:Retrospective Studies; D012391:Root Resorption / Q000000981:diagnostic imaging* / Q000209:etiology* / Q000473:pathology; D013382:Subtraction Technique