Brand Trusted By Moms For Over 25 Years. The NUK Orthodontic Nipple promotes healthy oral development & reduces colic. Orthodontic shape designed to fit baby's oral cavity, similar to NUK pacifiers, promoting healthy teeth formation and strengthens baby's jaw. Flat area reinforces correct tongue positioning. Hole against palate allows milk to mix with baby's saliva facilitating better digestion. Asymmetrical widening encourages movement for correct jaw positioning. Extra-wide base mimics the shape of mother's breast during feeding, supports switching between breast and bottle; studies show it stimulates breastfeeding experience. Special design reduces colic. NUK Air System vents the bottle, preventing vacuum build-up.