Treatment Effect Of 10600nm CO₂ Fractional Laser On Photoaging Of Guinea Pig Skin

Objective To investigate the effect of 10600nm CO2 Fractional laser which was applied to the Photoaging Skin of Guinea Pigs,and the different effect with different therapeutic density.Methods Twenty-four white female guinea pig , weigt 180-250g,were divided randomly into two groups(12 in each group):blank group and model group. Every guinea pig was shave off on the back for 8cm×10cm bare area everyday. Model group were expose 2 hour perday to two wavelength ultra violet irradiation(UVA and UVB) for 60 days. When photoaging skin models were complete, each guinea pig's back in model group was divided into four areas:A(act as blank area without any therapy),B(high density therapy),C(moderate density therapy),D(low density therapy). Pathological section was performed on 7th and 30th day. The number of fibroblasts(done on 7th day post-treatment), the thickness of dermis,the density of collagenous fiber and elastic fibers(done on 30th day post-treatment) were examined.Result Fibroblasts numbers in B,C and D areas increased significantly compared to A area(P<0.05) on the 7th day postoperatively, and B,C area were more significant than D area(P<0.05), meanwhile, there was no significant difference between B and C area. The thickness of dermis and the density of collagenous fiber in B,C,D areas were significantly increased compared to A area(P<0.05)on the 30th day,D area was less significant than B and C area (P<0.05), no significant difference between B and C area(P>0.05).There was no significant difference between A,B,C and D area in the measurement of elastic fibers density(P>0.05).Conclusion CO2 Fractional Laser can increase the number of Fibroblasts and the density of collagenous fiber and elastic fibers, which result in the improvement of the photoaging skin of guinea pig. It changed the dispose rather than density of elastic fiber posttreatment. Different therapy density result in different effect, the treatment with high and moderate therapeutic density were more effective than low therapeutic density.