Low-level laser therapy on the viability of skin flap in rats subjected to deleterious effect of nicotine.

OBJECTIVE

The purpose of this study was to evaluate the effect of 830-nm laser in blocking the action of nicotine on the viability of skin flap.

BACKGROUND DATA

The authors have analyzed the deleterious effect of cigarette smoke or nicotine on the skin flap alone with evidence of increased skin necrosis in the flap.

MATERIALS AND METHODS

Twenty-four Wistar-albino rats were divided into three groups of eight animals each: Group 1 (control), subjected to a surgical technique to obtain a flap for cranial base, laser irradiation simulation, and a subcutaneous injection of saline; Group 2, similar to Group 1, with subcutaneous injection of nicotine (2  mg/kg/day) for a period of 1 week before and 1 week after surgery; and Group 3, similar to Group 2, with skin flaps subjected to a λ 830-nm laser irradiation. The laser parameters used were: power 30 mW, beam area 0.07 cm(2), irradiance 429 mW/cm(2), irradiation time 84  sec, total energy 2.52  J, and energy density 36 J/cm(2). The laser was used immediately after surgery and for 4 consecutive days, in one point at 2.5  cm of the flap cranial base. The areas of necrosis were examined by two macroscopic analyses: paper template and Mini-Mop(®). The pervious blood vessels were also counted.

RESULTS

The results were statistically analyzed by ANOVA and post-test contrast orthogonal method (multiple comparisons), showing that the laser decreased the area of necrosis in flaps subjected to nicotine, and consequently, increased the number of blood vessels (p < 0.05).

CONCLUSIONS

The laser proved to be an effective way to decrease the area of necrosis in rats subjected to nicotine, making them similar to the control group.