title: A retrospective analysis of maxillary sinus septa on reformatted computerised tomography scans.
abstract: OBJECTIVE
  This study analysed 200 consecutive computerised tomography (CT) scans, reformatted with specialised software for the identification of maxillary sinus septa. All patients were routine implant patients who had undergone CT scans for dental implant planning.
  
  
  METHODS
  The data of two hundred consecutive patients (400 maxillary sinuses) who had been sent for CT scan, were reformatted with CT software. The group consisted of 115 edentulous and 85 dentate (below sinuses) patients. Septa were identified using three-dimensional (3D) reconstruction and panoramic views. No septa were included unless they were clearly visible on the 3D reconstruction. The prevalence, height and number of septa were analysed for both groups of patients.
  
  
  RESULTS
  The prevalence of sinus septa was found to be 69% (138 patients), with a significant number of these patients showing multiple septa (89/138). The mean age of the patients was 54 (+/-14). The prevalence of edentulous patients with septa (71%) was not statistically different from the dentate patients (66%) (P=0.7).
  
  
  CONCLUSIONS
  This study found a higher prevalence of patients with maxillary sinus septa than what has been reported previously. This may be due to the exact nature of the CT software and the ease of use of the 3D reconstruction for identification of septa. Another explanation could be that all septa that were visible on the 3D reconstruction were included and there was no minimum cut-off height. No significant differences were found between edentulous and dentate patients.
authors.affiliation: Department of Periodontics and Oral Medicine, School of Dentistry, University of Pretoria, Pretoria, South Africa. andrevanzyl@up.ac.za
authors.forename: Andre W
authors.initials: AW
authors.lastname: van Zyl
authors.forename: Willie F P
authors.initials: WF
authors.lastname: van Heerden
mesh_terms: D005260:Female; D006801:Humans; D021621:Imaging, Three-Dimensional; D007575:Jaw, Edentulous / Q000000981:diagnostic imaging; D008297:Male; D008443:Maxillary Sinus / Q000000981:diagnostic imaging*; D008875:Middle Aged; D010347:Patient Care Planning; D011857:Radiographic Image Interpretation, Computer-Assisted / Q000379:methods*; D012189:Retrospective Studies; D012984:Software; D014057:Tomography, X-Ray Computed