title: Rapid prototyping modelling in oral and maxillofacial surgery: A two year retrospective study.
abstract: BACKGROUND
  The use of rapid prototyping (RP) models in medicine to construct bony models is increasing.
  
  
  METHODS
  The aim of the study was to evaluate retrospectively the indication for the use of RP models in oral and maxillofacial surgery at Helsinki University Central Hospital during 2009-2010. Also, the used computed tomography (CT) examination - multislice CT (MSCT) or cone beam CT (CBCT) - method was evaluated.
  
  
  RESULTS
  In total 114 RP models were fabricated for 102 patients. The mean age of the patients at the time of the production of the model was 50.4 years. The indications for the modelling included malignant lesions (29%), secondary reconstruction (25%), prosthodontic treatment (22%), orthognathic surgery or asymmetry (13%), benign lesions (8%), and TMJ disorders (4%). MSCT examination was used in 92 and CBCT examination in 22 cases. Most of the models (75%) were conventional hard tissue models. Models with colored tumour or other structure(s) of interest were ordered in 24%. Two out of the 114 models were soft tissue models.
  
  
  CONCLUSIONS
  The main benefit of the models was in treatment planning and in connection with the production of pre-bent plates or custom made implants. The RP models both facilitate and improve treatment planning and intraoperative efficiency.
  
  
  BACKGROUND
  Rapid prototyping, radiology, computed tomography, cone beam computed tomography.
authors.affiliation: Department of Radiology, University of Helsinki and HUS Radiology (Medical Imaging Center).
authors.forename: Anni
authors.initials: A
authors.lastname: Suomalainen
authors.affiliation: Department of Maxillofacial Surgery, Helsinki University Hospital, Helsinki, Finland.
authors.forename: Patricia
authors.initials: P
authors.lastname: Stoor
authors.affiliation: Department of Maxillofacial Surgery, Helsinki University Hospital, Helsinki, Finland.
authors.forename: Karri
authors.initials: K
authors.lastname: Mesimäki
authors.affiliation: Department of Maxillofacial Surgery, Helsinki University Hospital, Helsinki, Finland.
authors.forename: Risto K
authors.initials: RK
authors.lastname: Kontio