The Best Under Stress: An Analysis of Breast Tissue Expander Response to External Forces

BACKGROUND: The use of breast tissue expanders (TEs) in breast reconstruction is accompanied by undesired changes to the chest wall and lateral plane. Breast TEs are designed to create a naturally formed breast pocket by capitalizing on the ductile response of skin tissue; however, in practice, the use of expanders is accompanied by undesired changes to the chest wall and lateral plane. OBJECTIVES: The authors of this study compared 3 comparably sized and commercially available breast TEs to assess the mechanical profile and functionality of each design. METHODS: Authors compared MENTOR Artoura PLUS Smooth (Irvine, CA), Allergan 133 Smooth (Irvine, CA), and Sientra AlloX2 Smooth (Santa Barbara, CA) filled to 100% of their label volume. The mechanical profile of TEs was assessed via vertical compression. Dimensions were recorded at baseline and percent changes were calculated at each compressive load (5-35 lbf intervals of 5 lbf). RESULTS: Base width and projection were recorded at compressive loads of 10, 20, and 35 lbs. For percent changes of base width, MENTOR had 0.98%, 2.09%, 3.84%; Allergan 4.21%, 9.15%, 15.52%; and Sientra 4.72%, 10.19%, 19.15%. For percent changes of projection, MENTOR had −19.06%, −25.44%, −30.88%, Allergan −35.53%, −42.90%, −50.09%, and Sientra −29.64%, −37.68%, −44.69%. For percent change of height, MENTOR had 1.44%, 2.62%, 4.27%, Allergan 10.26%, 16.49%, 22.97%, and Sientra 6.99%, 11.93%, 16.90%. MENTOR's TE had the most pronounced lower pole with volume expansion. CONCLUSIONS: The MENTOR TE demonstrated the least lateral deformation and projection loss across the range of compressive loads, as well as the highest force resistance compared with the other models. LEVEL OF EVIDENCE: 3: [Image: see text]