Evaluation of the effect of semi permanent filler and lidocaine added to fillers on neocollagenization

Aim: Dermal filler injections are frequently preferred in anti-aging treatment. One of the major complaints of patients during filler injections is pain. Polycaprolactone filler acts by stimulating neocollagenesis. While there is a great deal of literature on the use and efficacy of lidocaine with hyaluronic acid and calcium hydroxyapatite fillers, there is no detailed study on polycaprolactone filler. In our study, it was planned to compare histological and electron microscopic changes in tissue with lidocaine and non-lidocaine polycaprolactone filler with each other and with the control group. Material and Method: In the experiment, 30 female rats of the genus Wistar albino 1 year old, weighing 280-300 grams were used. 10 subjects were used in each group. Groups; Group A: Control, group B: Polycaprolactone and group C: Polycaprolactone + Lidocaine. The back region of the subjects was shaved and 0.2 cc polycaprolactone and polycaprolactone + lidocaine were applied to the points determined on the right and left sides. A 4 mm punch biopsy was taken from the marked area on the right at 2 months and from the marked area on the left at 4 months. In hematoxylin-eosin stained sections, dermis thickness averages were determined from three different points at x4 magnification, and the number of fibroblast / fibrocyte nuclei was counted in three different dermis areas (excluding capillary) at x40 magnification. In electron microscope, transverse sectioned collagen fiber count and collagen fiber diameter averages were determined in three different areas at x25000 magnification. Results: In the 4th month of the study, there was no statistically significant difference between fibroblasts count, collagen fibers count and the diameter of collagen fiber polycaprolactone and polycaprolactone + lidocaine (p> 0.05), and the dermis thickness was statistically significantly higher in the polycaprolactone group (p <0.05). The dermis thickness, fibroblast count, collagen fiber count and collagen fiber diameter of the control group were statistically significantly lower than the polycaprolactone and polycaprolactone + lidocaine groups (p <0.05). Conclusion: In our study, it was shown that adding lidocaine to polycaprolactone filler does not change the effectiveness of the filler. Key Words: dermal fillers, lidocaine, polycaprolactone, skin aging