Mastication and swallowing: 1. Functions, performance and mechanisms.

The process of mastication involves movements of the tongue, lips and cheeks as well as the more obvious actions of the teeth and jaws. In recent years there have been significant advances in our knowledge of the relationships between these movements in human beings and of how the processes of mastication are related to the associated events of swallowing. In this, the first of two papers, we review the role of mastication in food processing and nutrition and the effect of tooth loss on masticatory performance.The paper also reviews new information on masticatory and swallowing functions in human beings eating naturally. The review relates this knowledge to clinical dentistry, notably to the relevance of a good dentition to the digestive process and practical considerations in the replacement of missing teeth. CLINICAL RELEVANCE: Dentists should understand the process of mastication because an adequate dentition can facilitate the general health and well-being of their patients.This understanding can also inform the clinical management of patients with a depleted dentition or otherwise impaired masticatory system.