title: The most distal palatal ruga for placement of orthodontic mini-implants.
abstract: OBJECTIVE
  To evaluate the stability and bone availability of the most distal (third) palatal ruga, as an anatomical region for safe insertion of orthodontic mini-implants (OMIs) in the anterior palate.
  
  
  METHODS
  Orthodontic records of 35 patients were analysed. Initial (T1) and final (T2) study models were bisected and the outline of the palatal contour was marked on the surface. Models were scanned and the palatal contours were superimposed on the palatal structures on the respective initial and final cephalometric images. Cephalometric measurements were used to assess vertical (3rdRug-PP, 2ndRug-PP, and 1stRug-PP), and oblique bone levels (3rdRug-U1, 2ndRug-U1, 1stRug-U1, and 3rdRug-U1(o)). Paired Student's t-test was used to compare measurements between T1 and T2.
  
  
  RESULTS
  The position of the third palatal ruga remained stable during orthodontic treatment (Δ2ndRug-3rdRug P = 0.1mm; P = 0.61 and Δ1stRug-3rdRug P = 0.2mm; P = 0.39). Bone availability also remained adequate (3rdRug-U1T2 (o) = 9.9mm).
  
  
  CONCLUSIONS
  The third palatal ruga is a reliable clinical landmark to evaluate bone availability for the placement of OMIs in the anterior palate.
authors.affiliation: *Private Practice, Reinheim, Germany, **Department of Orthodontics, University of Heidelberg, Heidelberg, Germany.
authors.forename: Jan
authors.initials: J
authors.lastname: Hourfar
authors.affiliation: ***Private practice, Traben-Trarbach, Germany, ****Department of Orthodontics, University of Homburg/Saar, Homburg/Saar, Germany.
authors.forename: Björn
authors.initials: B
authors.lastname: Ludwig
authors.affiliation: *****Department of Orthodontics, Guy's and St Thomas' NHS Foundation Trust, London, UK, and.
authors.forename: Dirk
authors.initials: D
authors.lastname: Bister
authors.affiliation: ****Department of Orthodontics, University of Homburg/Saar, Homburg/Saar, Germany.
authors.forename: Anna
authors.initials: A
authors.lastname: Braun
authors.affiliation: ******Department of Orthodontics and Dentofacial Orthopedics, Tufts University School of Dental Medicine, Boston, MA, USA georgios.kanavakis@tufts.edu.
authors.forename: Georgios
authors.initials: G
authors.lastname: Kanavakis
mesh_terms: D059925:Anatomic Landmarks / Q000033:anatomy & histology*; D002508:Cephalometry / Q000379:methods; D002648:Child; D015921:Dental Implants; D005260:Female; D005500:Follow-Up Studies; D006801:Humans; D008297:Male; D008904:Miniaturization; D003765:Models, Dental; D052280:Orthodontic Anchorage Procedures / Q000295:instrumentation*; D016382:Orthodontic Appliance Design; D021362:Palate, Hard / Q000033:anatomy & histology*; D012189:Retrospective Studies
chemical_list: D015921:Dental Implants