Biomechanical properties of superficial musculoaponeurotic system tissue with vs without reinforcement with poly-4-hydroxybutyric acid absorbable mesh.

IMPORTANCE It is unknown whether poly-4-hydroxybutyric acid (P4HB)-reinforced superficial musculoaponeurotic system tissue (SMAS) plication techniques will support SMAS imbrication and plication and potentially improve outcomes in rhytidectomy. OBJECTIVES To evaluate the biomechanical properties (tissue breaking strength, suture tearing force, and stress relaxation) of the SMAS with vs without reinforcement with P4HB absorbable mesh and to correlate these results with potential clinical applications. DESIGN, SETTING, AND SAMPLES In a cadaver study at an academic setting, 12 fresh frozen cadaver heads were used. Rhytidectomy incisions were made, and the SMAS was harvested and prepared for strength and stress testing using an Instron device. MAIN OUTCOMES AND MEASURES Tissue breaking strength and suture tearing force were analyzed. Stress relaxation test results were also assessed. The results of the SMAS samples alone were compared with those reinforced with P4HB absorbable mesh. RESULTS Overall, there were significant differences noted in tissue breaking strength and suture tearing force between the 2 groups. When the SMAS was reinforced with absorbable mesh, significant improvements were observed in tissue breaking strength (P < .001) and suture tearing force (P < .003). In addition, less variability was demonstrated in the maximum tensile load-bearing quality of the SMAS when the repair was reinforced with P4HB. CONCLUSIONS AND RELEVANCE Reinforcement with P4HB absorbable mesh improves tissue breaking strength and suture tearing force in cadaveric SMAS. It also reduces the variability in load vs displacement seen among samples tested. These data suggest that P4HB-reinforced SMAS imbrication would support higher loads and provide more consistent, long-lasting SMAS support among patients undergoing rhytidectomy. Further studies are needed to correlate these data with clinical outcomes in rhytidectomy.