To ensure that feeding by bottle replicates breast feeding as closely as possible, NUK took a mothers breast as their model when designing the NUK orthodontic teat shape. The unique NUK orthodontic shape was developed over 50 years ago after intensive research by two German orthodontists. Their research found that prolonged use of conventional round teats and soothers could cause oral abnormalities. They therefore decided to develop a teat that is based on the shape of a mothers nipple during breast-feeding. By closely mimicking the sucking action of breast-feeding, NUK teats and soothers encourage the correct oral development for your baby.