Abstract
Development of an accurate prognosis is an integral component of treatment planning in the practice of periodontics. Prior work has evaluated the validity of using various clinical measured parameters for assigning periodontal prognosis as well as for predicting tooth survival and change in clinical conditions over time. We critically review the use of multivariate classification and regression trees (CART) for survival in developing evidence-based periodontal prognostic indicators. We focus attention on two distinct methods for multivariate CART for survival: the marginal goodness-of-fit approach and the multivariate exponential approach. A number of common clinical measures have been found to be significantly associated with tooth loss from periodontal disease, including furcation involvement, probing depth, mobility, crown/root ratio and oral hygiene. However, the inter-relationships among these measures, as well as the relevance of other clinical measures to tooth loss from periodontal disease (such as bruxism, family history of periodontal disease and overall bone loss), remain less clear. Although the inferences that can be drawn from any single study are necessarily limited, application of new approaches in epidemiological analyses to periodontal prognosis, such as CART for survival, should yield important insights into our understanding and treatment of periodontal diseases.