The sucking reflex is one of the most basic and earliest newborn reflexes, and it is essential to the growth and development of the newborn (<2 months old) and infant (2 months–1 year old). Newborns and infants often exhibit self-soothing behaviour such as thumb or finger sucking or sucking on a pacifier/ dummy or blanket. However, when these habits extend further into the toddler years (ages 1–3 years) and beyond, they can negatively affect facial growth and development. Other habits that can damage the teeth and/or cause malalignment of the teeth and jaws include chewing or biting nails, lip biting or lip sucking, tongue thrusting and teeth grinding (bruxism).