This chapter discusses the histology of some structures present in relation to the oral cavity. The wall of the oral cavity is made up partly of bone, and partly of muscle and connective. These structures are lined by mucous membrane. The external surface of the lip is lined by true skin in which hair follicles and sebaceous glands can be seen. The enamel is the hardest material in the body and is made up almost entirely of inorganic salts. Dentine is permeated by numerous fine canaliculi called dentinal tubules that pass radially from the pulp cavity towards the enamel. The odontoblasts persist as a lining for the pulp cavity and cytoplasmic processes from these cells extend into the dentinal tubules. The surface of the tongue is covered by mucous membrane lined by stratified squamous epithelium and each papilla consists of a lining of epithelium and a core of connective tissue. The cells present in taste buds are elongated and are vertically orientated, those towards the periphery being curved like crescents and perform a supporting function.