Figure 3.8 Community Periodontal Index of Treatment Needs (CPITN).
Figure 3.9 UK national survey (representing population) data, 1998, on the prevalence of: (a) pockets, and (b) clinical attachment loss (CAL).
Figure 3.10 The prevalence of periodontitis based on: (a) US national survey (representing population) data, 1985–86, and (b) US National Health and Nutrition Examination Surveys (NHANES) data, 1988–94 and 1999–2004.
Epidemiology is the study of the distribution and determinants of health-related states or events in specified populations, and the application of this study to the control of health problems (Fig. 3.1).