Effect of the CO2 milliwatt laser on tensile strength of microsutures

Laser-assisted tissue repair is often accompanied by a high dehiscence rate, which may be due to alterations in suture material after laser exposure. The goal of this study was to investigate the effect of CO2 laser irradiation on the tensile strength of microsurgical suture material. 10-0 nylon and 25 microns stainless steel threads were exposed to 12 combinations of power densities (62, 124, and 186 W/cm2) and pulse durations (0.5, 1, 2, 3 s) and tested on a tensometer for their tensile strength. At power densities of 186 W/cm2, the 10-0 nylon thread disrupted during laser irradiation, regardless of pulse duration. This was also the case at power densities of 124 C/cm2 for 2 s and 3 s pulse duration. At 124 W/cm2 for 0.5 and 1 s, the tensile strength decreased with 70% relative to the control. At 62 W/cm2, the tensile strength gradually decreased from 100% (0.5 s pulse duration) to 50% (3 s pulse duration) relative to control. Stainless steel thread resisted all laser irradiations. The 10-0 nylon thread is significantly compromised by irradiation with the CO2 milliwatt laser and therefore meticulous care should be taken not be irradiate the sutures during laser tissue welding