Large openings allow babys skin to breathe openings in the collar allow better air circulation, keeping your babys skin drier for optimal comfort. orthodontic pacifier designed for natural oral development our soft orthodontic silicone pacifiers support natural movements of the mouth muscles and reduce the risk of malocclusion. the narrow neck of the pacifier reduces pressure between the tongue and the palate. philips avent ultra pacifiers are independently validated by the oral health foundation. made from 100% food-grade silicone, they are more durable and resistant than rubber (latex) pacifiers and do not contain bpa, bps, phthalates, pvc or polycyclic aromatic hydrocarbons. babies love it, with a 98% pacifier acceptance rate*** textured silicone nipples are designed to mimic the feel of a mothers breast. Proof of their effectiveness: 98% of parents found that their babies accepted Philips Avent Ultra pacifiers.