The human lips are everted, exposing part of the mucous membrane. If the mucous membrane protrudes excessively, it can cause the lips to appear too thick. "Thick lips" refer to when a man's upper lip exceeds 9 mm in thickness and the lower lip exceeds 10.5 mm; for women, the upper lip exceeds 8 mm and the lower lip exceeds 9 mm.
If the mucous glands below the lip mucosa become hypertrophic due to various reasons, under the effect of gravity, they will have a tendency to droop. When speaking or smiling, the contraction of normal lip muscles forces the prolapsed mucosal tissue to sag and evert more severely, forming double-lip deformity.
Double-lip deformities mainly occur on the upper lip and are most evident during puberty. This deformity significantly affects appearance; when the mouth is closed, the deformity is not obvious, but when opened, two lip edges can be seen. There is a horizontal groove between the two lip edges, and when laughing, two clear red lips appear.
Both thick lips and double lips can be corrected through cosmetic surgery.
The procedure for reducing thick lips involves making an incision at the junction of the vermilion border of the upper and lower lips. Depending on the degree of lip thickness, a wedge-shaped or sawtooth-shaped section of oral mucosa and muscle is removed, then the incision is directly sutured together to make the thick lips thinner. The surgical scar from this procedure is hidden inside the mouth, producing ideal results.
The treatment principle for double lips is partial resection to restore the normal shape of the red lip. There are two types of surgeries: "wedge resection method" and "horizontal and vertical wedge resection method." The wedge resection method involves making a wedge-shaped incision along the edge of the double lip, removing the mucosa and submucosal tissue in a wedge shape, then suturing the wound layer by layer. The horizontal and vertical wedge resection method involves sewing one stitch on each side of the upper lip and pulling the two threads to evert the upper lip. A horizontal wedge-shaped incision is made on both sides where the double lip protrudes, and a vertical incision is made in the midline. After removing the excess mucosa and submucosal tissue, the wound is sutured layer by layer.