Anticipating Local Flaps Closed-Form Solution on 3D Face Models Using Finite Element Method.

Kwan, Zhenli; Khairu Najhan, Nur Nadirah; Yau, Yat Huang; Luximon, Yan; Nor, Fethma M

A realistic three-dimensional (3D) computational model of skin flap closures using Asian-like head templates from two different genders, male and female, has been developed. The current study aimed to understand the biomechanics of the local flap designs along with the effect of wound closures on the respective genders. Two Asian head templates from opposite genders were obtained to use as base models. A third-order Yeoh hyperelastic model was adapted to characterize as skin material properties. A single layer composed of combined epidermis and dermis was considered and the models were thickened according to respective anatomical positions. Each model gender was excised with a fixed defect size which was consequently covered by three different local flap designs namely advancement, rotation, and rhomboid flaps. Post-operative simulation presented various scenarios of skin flap closures. Rotation and rhomboid flaps demonstrated maximal tension at the apex of the flap for both genders as well as advancement flap in the female face model. However, advancement flap closure in the male face model presented otherwise. Yet, the deformation patterns and the peak tension of the discussed flaps were consistent with conventional local flap surgery. Moreover, male face models generated higher stresses compared to the female face models with a 70.34% mean difference. Overall, the skin flap operations were executed manually and the designed surgery model met the objectives successfully while acknowledging the study limitations. This article is protected by copyright. All rights reserved.