Methodologies for evaluating long-term stability of dental relationships after orthodontic treatment

A comprehensive review of literature which considers methodologies for studying long-term occlusal stability is presented. This article focuses on the evaluation of plaster study models because occlusal changes are best reflected in longitudinal casts. Of particular interest is the assessment of crowding in the dentition and the various physical and mathematical procedures used to evaluate the measurement of space available. Indices used to assess the overall occlusal results of treatment are also presented.