To clarify, ankyloglossia or tongue-tie is a condition in which the lingual frenum,* the bit of tissue connecting the bottom of the tongue to the lower jaw, is either too short or anteriorly placed, thus limiting the mobility of the tongue.

The operation to remedy this is most often called a frenotomy.

There is great difference in opinion as to how common this condition is, estimates ranging from .05% to 4.8%. This difference is largely because no one can agree on exactly what counts as ankyloglossia. There is no set length that a lingual frenum should be, making the diagnosis somewhat subjective. Regardless of the exact diagnostic criteria used, males are about twice as likely to be born with tongue-tie as are females.

Ankyloglossia is often believed to be a cause of articulation errors in children, although it appears that cutting the frenum may also in some cases reduce the child's control of the tongue, and thus also increase articulation difficulties. The effects of ankyloglossia decrease with age, and many cases 'disappear' by the age of four as the tongue-tip grows and lengthens.

Previous to the 1800s, it was routine to clip the frenum at birth. Given the time period, this was a dangerous practice, which could result in deadly infections. Tongue-tie was associated with speech problems, particularly lisping and inability to pronounce certain sounds. This practice was not limited to babies with tongue-tie.

Frenum is also spelled fraenum, fraenulum, and frenulum.