Evaluating periodontal disease misclassification mechanisms under partial-mouth recording protocols

Aim. To evaluate the assumptions underlying the use of partial-mouth recording protocols and the associated mechanisms of potential misclassification of periodontal disease.

Methods. Using data from 640 participants in the Veterans Affairs Dental Longitudinal Study, we compared tooth-specific and site-specific clinical measures, and calculated sensitivity and specificity of different partial-mouth recording protocols by applying widely used surveillance case definitions for periodontitis as the full-mouth reference standard. Additionally, we evaluated alternative case definitions for partial-mouth recording protocols that accounted for the reduction in numbers of teeth under observation.

Results. In this cohort, periodontitis presented as a generalized condition in that measures of clinical severity did not differ meaningfully according to site measured, oral quadrant or jaw. Importantly, we found that the sensitivity of disease classification under partial-mouth recording protocols was a function of the number of teeth and sites under observation and the case definition applied. Sensitivity increased when case definitions were modified to account for the smaller number of teeth under observation with partial-mouth recording protocols. However, specificity estimates were reduced.

Conclusions. Misclassification of periodontal disease by partial-mouth recording protocols is not random, even if sites under observation are randomly selected. Partial-mouth recording protocols can be selected/modified to maximize sensitivity, but they do so at the expense of bias in mean measures of severity.