The influence of partial and full-mouth recordings on estimates of prevalence and extent of lifetime cumulative attachment loss: A study in a population of young male military recruits

Background: Previous studies have shown that the use of index teeth may underestimate the prevalence of chronic periodontitis in adults. However, there is little information on the effect of using index teeth to estimate the prevalence of early periodontitis in younger adults and the effect this may have on planning treatment needs and health care resources. The aim of this study was to compare full mouth examination with partial examination using index teeth in a group of young British males. Methods: One hundred subjects aged between 16 and 20 years (mean 17 years) on entry to the study were examined at baseline, 12 months later, and 30 months later. Lifetime cumulative attachment loss (LCAL) greater than or equal to1 mm was measured on the mesio-buccal, disto-buccal, mesio-lingual, and disto-lingual surfaces of all teeth, excluding third molars. All data were entered into a database. The indices used to express LCAL were prevalence, defined as the percentage of subjects with LCAL greater than or equal to1 mm, 2 mm, or 3 mm, and extent, defined as the percentage of sites with LCAL greater than or equal to1 mm, 2 mm, or 3 mm. Two sets of index teeth were chosen to compare with full mouth recordings, Ramfjord index teeth and the Periodontal Index for Treatment (PIT) teeth. Results: The prevalence of LCAL greater than or equal to1 mm was similar (approaching 100%) for the full mouth and both partial mouth recordings. However, as LCAL increased from a minimum of 1 to 3 mm, partial mouth recording resulted in an underestimation of the prevalence of disease. LCAL greater than or equal to2 mm was underestimated by up to 22% and LCAL greater than or equal to3 mm by up to 36%. The extent of LCAL was less affected by partial mouth recording, in that the percentage of sites with no sign of early attachment loss was underestimated by up to 11%. However, the percentage of sites with LCAL greater than or equal to1 mm and 2 mm were overestimated by 11% and, 7% respectively. Conclusions: These data indicate that the use of index teeth in epidemiological studies which include young adults may result in an underestimation of the prevalence of early periodontitis and an overestimation of the extent.