Dental occlusion often rhymes with confusion, discrediting many research protocols. The profession seems to be in "major chaos about occlusion." This may be due to the lack of a precise classification of occlusal dysfunctions. We suggest using a classification based on the separation of three occlusal functions, with the identification of precise, objective clinical diagnostic criteria. This article aims to define a precise classification of occlusal functions, in order to be able to establish a positive diagnosis of occlusal disorders. This occlusal analysis method could then be used in the daily practice of dentists and orthodontists, with a view to align epidemiological studies that focus on occlusion, in order to obtain results capable of comparison in different studies.