Dr. Greene's Answer
During fetal development, cords of tissue called frenula form in the front-center of the mouth, beginning as early as 4 weeks of gestation. The word “frenulum” comes from the Latin word for bridle. A bridle can be used to guide a horse. In roughly the same way, the frenula guide the development of the structures of the mouth. Early in development, the frenula are important, strong cords, which then recede over time. After birth, they are still useful in guiding the positions of the baby teeth as they come in.
The tiny cord between the center of the upper lip and the center of the upper gum is called the labial frenulum (or lip frenulum). If you slip your tongue up where your upper lip meets your upper gum, you can probably still feel a remnant of your labial frenulum.
Another cord between the base of the tongue and the floor of the mouth or the lower gum is called the lingual frenulum. If you lift your tongue up and look in a mirror, you probably can see the strand of tissue connecting the bottom of your tongue to the floor of your mouth — what is left of your lingual frenulum.
In some kids, the lingual frenulum is short and taut after birth, partially restricting movement of the tongue. This condition is called ankyloglossia (don’t doctors have great names for things?) — more commonly known as tongue-tie.
Most cases of ankyloglossia require no intervention. Frenuloplasty (cutting the cord between the base of the tongue and the floor of the mouth or the lower gum) is considered if the lingual frenulum inteferes with breastfeeding due to poor latch or maternal nipple pain (Pediatrics 2002; 110; e63).
In most of these children, the frenulum continues to recede during the entire first year. Their parents get to watch a part of development that usually happens in the hidden inner sanctum of the uterus.