Testing reliability of plaque and gingival indices. Two methods.
This investigation was undertaken to compare two methods of interexaminer and intraexaminer reliability in the evaluation of Plaque and Gingival Indices prior to a study of toothbrushing. Inter-/intraexaminer reliabilities were compared using a projected slide series consisting of 40 slides of clinical examples of gingival inflammation and plaque accumulation. Time between assessments was three weeks. Using the slide technique, intraexaminer reliability was established for: (1) Gingival Indices and (2) Plaque Indices. Interexaminer reliability was also established for Gingival Indices. Interexaminer reliability could not be established for Plaque Indices on the first assessment but was established on the post-assessment. Intraexaminer reliability was also determined through clinical examinations of patients. A third clinician was used to manipulate the tissue while investigators evaluated bleeding on provocation and plaque accumulation. Significant results were established for the Gingival Indices and Plaque Indices. Results of this investigation suggest that significant inter-/intraexaminer reliabilities may be obtained for gingival indices using the slide technique. In addition, the clinic technique appeared useful for assessing interexaminer reliability for Gingival Indices. Plaque Indices using the slide technique required more practice than those using the clinic technique.