Many different kinds of teeth are found in the animal kingdom. Not only do they vary between species, but also within a mouth, both by generation (baby teeth versus adult ones) and by type (front teeth versus back ones). ‘Types and parts of teeth’ explains the variation within a mouth, tooth generations, and tooth types (incisors, canines, premolars, and molars). The 19th-century Cope–Osborne model provided an early guide to tooth evolution and variation between species, but has been superseded by further dental research and understanding of developmental biology. The basic types of tissue that make up tooth structure — enamel, dentine, cementum, and pulp — are described.