Computer-aided design and three-dimensional printing improves symmetry in heminasal reconstruction outcomes

Abstract

Symmetry and balance in nasal reconstruction can be hard to achieve. Traditionally, a foil template modeled after the unaffected contralateral side is used in the design of a forehead flap. Crude two-dimensional models often generate underwhelming results. To better simulate complex nasal topography, three-dimensional printing technology was applied to nasal reconstruction. Between May 2012 and October 2016, twenty patients underwent forehead flap nasal reconstruction for heminasal deformities. Ten reconstructions were guided with prefabricated three-dimensional templates (CAD/CAM), and ten patients underwent traditional nasal reconstruction without CAD/CAM. In the CAD/CAM group, two templates were printed: contour guide and framework guide. These were a reference for skin flap design and cartilage framework design, respectively. Photographic records and photogrammetry was used to evaluate results. The mean follow-up time was 19.3 months (range, 6 months to 38 months) in the control group and 17.4 months (range, 7 months to 35 months) in the CAD/CAM group. Without CAD/CAM, there was asymmetry in alar width, alar area, nostril height, width and area (p < 0.05) between reconstructed and native structures. In the CAD/CAM group, there were asymmetries of nostril-related parameters only. After quantifying asymmetries as a percentage, the CAD/CAM group demonstrated more symmetric reconstructions, particularly in alar width (p=0.043) and alar area (p=0.003). When CAD/CAM guidance and three-dimensional printing was used, there was greater symmetry between reconstructed and native structures of the nose.