title: Cortical bone thickness at common miniscrew implant placement sites.
abstract: BACKGROUND
  The purpose of this study was to assess age, sex, and regional differences in the cortical bone thickness of commonly used maxillary and mandibular miniscrew implant placement sites.
  
  
  METHODS
  Cone-beam computed tomography images, taken at 0.39-mm voxel size, of 52 patients, including 26 adolescents (13 girls, ages 11-13; 13 boys, ages 14-16) and 26 adults (13 men and 13 women, ages 20-45), were evaluated. The cone-beam computed tomography data were imported into 3-dimensional software (version 10.5, Dolphin Imaging Systems, Chatsworth, Calif); standardized orientations were used to measure cortical bone thickness at 16 sites representing the following regions: 3 paramedian palate sites, 1 infrazygomatic crest site, 4 buccal interradicular sites of the mandible, and 4 buccal and 4 lingual interradicular sites in the maxilla.
  
  
  RESULTS
  Multivariate analysis of variance (MANOVA) showed no significant differences in cortical bone thickness between the sexes. There were significant (P <0.05) differences between adolescents and adults, with adult cortices significantly thicker in all areas except the infrazygomatic crest, the mandibular buccal first molar-second molar site, and the posterior palate site. Cortical bone was thicker in the posterior than in the anterior mandibular sites. In the adults, interradicular bone in the maxillary first premolar-second premolar, and second premolar-first molar sites was thicker than bone at the lateral incisor-canine and first molar-second molar sites. Anterior paramedian palatal bone was significantly thicker than bone located more posteriorly. The mandibular buccal and infrazygomatic crest regions had the thickest cortical bone; differences between the maxillary buccal, the maxillary lingual, and the palatal regions were small.
  
  
  CONCLUSIONS
  Maxillary and mandibular cortical bones at commonly used miniscrew implant placement sites are thicker in adults than in adolescents. There are also differences in cortical bone thickness between and within regions of the jaws that must be considered when placing miniscrew implants.
authors: Orthodontic Department, University of North Carolina, Chapel Hill, USA.
authors: David
authors: D
authors: Farnsworth
authors: P Emile
authors: PE
authors: Rossouw
authors: Richard F
authors: RF
authors: Ceen
authors: Peter H
authors: PH
authors: Buschang
mesh_terms: D000293:Adolescent; D000328:Adult; D000367:Age Factors; D000818:Animals; D001641:Bicuspid / Q000000981:diagnostic imaging; D015519:Bone Density / Q000502:physiology; D001863:Bone Screws; D002648:Child; D054893:Cone-Beam Computed Tomography / Q000379:methods; D003481:Cuspid / Q000000981:diagnostic imaging; D015921:Dental Implants; D005260:Female; D006801:Humans; D007091:Image Processing, Computer-Assisted / Q000379:methods; D021621:Imaging, Three-Dimensional / Q000379:methods; D007180:Incisor / Q000000981:diagnostic imaging; D008297:Male; D008334:Mandible / Q000033:anatomy & histology* / Q000000981:diagnostic imaging; D008437:Maxilla / Q000033:anatomy & histology* / Q000000981:diagnostic imaging; D008875:Middle Aged; D008963:Molar / Q000000981:diagnostic imaging; D052280:Orthodontic Anchorage Procedures / Q000295:instrumentation*; D010159:Palate / Q000033:anatomy & histology / Q000000981:diagnostic imaging; D015203:Reproducibility of Results; D012737:Sex Factors; D034421:Sus scrofa; D014092:Tooth Root / Q000000981:diagnostic imaging; D055815:Young Adult; D015050:Zygoma / Q000033:anatomy & histology / Q000000981:diagnostic imaging
chemical_list: D015921:Dental Implants