Clinical signs of root caries: measurement issues from an epidemiologic perspective.

The measurement of root caries using a relatively precise, utilitarian, and universally-acceptable methodology based upon clinical signs is a critical and necessary step in the progression of the epidemiologic study of this oral disease. While a clinician directly involved in the care of a patient will always incorporate spontaneous judgment-based-upon-experience into the diagnostic process, the clinical investigator must rely upon a much more standardized approach to the diagnosis of root caries. A comprehensive overview of the current epidemiologic research findings and methodologic literature for root caries precedes a series of discussions on methodologic issues that relate to the measurement of root caries in epidemiologic study conditions. Topics discussed include: (1) appropriate categories of lesions for inclusion (active vs. inactive and supragingival vs. subgingival lesions), (2) surface visibility issues (clinical treatment effects and oral debris accumulations), and (3) examination techniques (examination instruments and use of radiographs). The final section of this article proposes seven diagnostic conventions for use by investigators when they are diagnosing root caries in descriptive, analytical, and experimental epidemiologic studies.