Description:
<jats:p><jats:bold>Background:</jats:bold> Data from whole‐mouth examinations are the gold standard for accurate assessment of periodontal disease. Since periodontal destruction exhibits left‐right symmetry, however, it is hypothesized that a half‐mouth exam provides an appropriate alternative to whole‐mouth assessment, with considerable advantage over a more limited partial‐mouth assessment of index teeth.</jats:p><jats:p><jats:bold>Methods:</jats:bold> Data from 2 untreated populations were utilized in the analyses. Half‐mouth (random diagonal quadrants) and Ramfjord teeth assessment was compared with whole‐mouth assessment as follows. Intraclass correlation coefficients (ICCs) were calculated for mean plaque index (PI), gingival index (GI), probing depth (PD), and clinical attachment level (CAL) and for percentage of sites with PD ≥4, 5, or 6 mm; CAL ≥3, 4, 5, or 6 mm; and recession ≥3 mm to determine the agreement between the whole‐ and partial‐mouth assessment. Disease prevalence was also determined for both whole‐ and partialmouth assessments.</jats:p><jats:p><jats:bold>Results:</jats:bold> For mean PI, GI, PD, and CAL, both half‐mouth and Ramfjord teeth assessment provided an acceptable alternative to whole‐mouth assessment (ICCs >0.92). For percentage of sites above a specified threshold, ICCs were generally greater than 0.90 in all age cohorts for half‐mouth assessment, but consistently lower for Ramfjord teeth assessment. Ramfjord teeth assessment also considerably underestimated disease prevalence compared with half‐mouth assessment.</jats:p><jats:p><jats:bold>Conclusions:</jats:bold> These results support the use of a half‐mouth examination procedure, to conserve time, limit cost, and reduce patient and examiner fatigue while providing maximal clinical information. Ramfjord teeth assessment was not as suitable for evaluation of either disease extent or prevalence. <jats:italic>J Periodontol 2002;73:975‐981.</jats:italic></jats:p>