The frenulum of the mouth is the mucous membrane of the mouth that joins the ventral side of the tongue, limiting its movements within a specific space; the frenulum labii superioris and the frenulum labii inferioris on the buccal side of the upper and lower lips, connect the cheeks to the fixed gingiva in the midline between the incisors. Their primary function is stabilizing the upper and lower lip and the tongue. Frenectomy is a surgical procedure to provide additional freedom of movement to the lip and tongue.