Fine lines or rhytids are created by multiple chronic and degenerative factors on the skin. For this reason, there are different treatment tools and techniques based on the etiology of the wrinkle, where it is on the face, and its depth and associated skin conditions.
Patients present as early as the third decade in light-skinned individuals and in later age groups for more highly pigmented skin types with a complaint of fine lines, crepelike wrinkles, and poor texture of the facial skin.
The basic cause of fine rhytids is a degeneration of the dermal structure of collagen and elastin, both quantitative and qualitative. The causes are both intrinsic and extrinsic. Aging factors result in a quantitative loss of collagen and elastin with a loss of structural integrity. In addition, the loss of underlying subcutaneous tissue reduces the fullness of facial skin adding to overlap with appearance of fine lines. Changes in the underlying muscles that insert in the skin result in hyperdynamic wrinkles and can remain as wrinkles at rest.7
Added UV factors cause collagen to intertwine, permanently elongate, and shrink in size and shape. Elastic fibers are designed to exhibit extensibility and elasticity or the ability to restore original shape after stretching. UV elastolysis creates the coil of elastin interfering with its ability to recoil or restore original shape. Collagenolysis or the histologic appearance of degenerative collagen impairs the structural framework of the skin creating thinning and ptosis. Wrinkles thus form over areas of movement based on both factors.8
Fine lines first appear over areas of repetitive movement and skin stretch. This is why we first see wrinkles in areas of motion or expression such as glabella, forehead, crow’s-feet, and lips. Added to this are the extrinsic factors of excessive UV; smoking, especially around the mouth; sleep lines on cheeks, etc.