Dimensional accuracy of computer-aided design/computer-assisted manufactured orbital prostheses.
OBJECTIVE
The aim of this research was to assess the dimensional accuracy of orbital prostheses based on reversed images generated by computer-aided design/computer-assisted manufacturing (CAD/CAM) using computed tomography (CT) scans.


METHODS
CT scans of the faces of 15 adults, men and women older than 25 years of age not bearing any congenital or acquired craniofacial defects, were processed using CAD software to produce 30 reversed three-dimensional models of the orbital region. These models were then processed using the CAM system by means of selective laser sintering to generate surface prototypes of the volunteers' orbital regions. Two moulage impressions of the faces of each volunteer were taken to manufacture 15 pairs of casts. Orbital defects were created on the right or left side of each cast. The surface prototypes were adapted to the casts and then flasked to fabricate silicone prostheses. The establishment of anthropometric landmarks on the orbital region and facial midline allowed for the data collection of 31 linear measurements, used to assess the dimensional accuracy of the orbital prostheses and their location on the face.


RESULTS
The comparative analyses of the linear measurements taken from the orbital prostheses and the opposite sides that originated the surface prototypes demonstrated that the orbital prostheses presented similar vertical, transversal, and oblique dimensions, as well as similar depth. There was no transverse or oblique displacement of the prostheses.


CONCLUSIONS
From a clinical perspective, the small differences observed after analyzing all 31 linear measurements did not indicate facial asymmetry. The dimensional accuracy of the orbital prostheses suggested that the CAD/CAM system assessed herein may be applicable for clinical purposes.
Marafon
Priscila Galzo
PG
Department of Maxillofacial Surgery, Prosthesis and Traumatology, School of Dentistry, University of São Paulo, Brazil.
Mattos
Beatriz Silva Câmara
BS
Sabóia
Antonio Carlos Lorenz
AC
Noritomi
Pedro Yoshito
PY
D000328:Adult; D002508:Cephalometry; D017076:Computer-Aided Design; D005260:Female; D006801:Humans; D007091:Image Processing, Computer-Assisted / Q000379:methods; D021621:Imaging, Three-Dimensional / Q000379:methods; D008297:Male; D008953:Models, Anatomic; D009915:Orbit / Q000033:anatomy & histology; D017233:Orbit Evisceration; D020273:Orbital Implants; D011474:Prosthesis Design; D012826:Silicone Elastomers / Q000737:chemistry; D012984:Software; D013499:Surface Properties; D014057:Tomography, X-Ray Computed / Q000379:methods
D012826:Silicone Elastomers; C078082:silastic 4-4210