Age-dependent changes in the size of the upper lip in Bulgarians.

Age-dependent changes in the width and height of the upper lip were studied in 2,300 healthy Bulgarians aged from 3 days to 102 years, for the purposes of cheiloplasty in surgery and of visual art. It has been established that at the moment of birth, the upper lip is one of the most developed organs of the human body in both sexes and that it grows in size up to the age of 80 years, completing its intensive growth during the pre-school age while in the years of puberty it does not show the growth jump characteristic of the organism as a whole. In the males, the lip remains larger during the whole period of postnatal ontogenesis except for the early childhood; the difference in the height is most expressed (3.08 mm) in the 9th decade, and in the width (5.24 mm) even later. The conclusion has been drawn that cheiloplasty can be performed at any age including the first days after birth, the dimensions obtained at the age intervals under study serving as standards.