[SBI verus GI: a clinical study].
The goal of the present study was to compare the sensitivity of the Gingival Index (GI) and the Sulcus Bleeding Index (SBI). The study was performed on 111 Swedish and 119 Swiss children, 11 to 15 years old. Two investigators examined 22 gingival units in the anterior region of each child, one using the GI and the other the SBI. The examinations were conducted separately. In order to test the sensitivity of the indices the index values for each gingival unit were divided into 2 groups: the first group included all values SBI = 0, GI > 0 and the second group all values GI = 0, SBI > 0 (all other relationships were ignored). These 2 groups were compared using the @chi-squared" test for each gingival unit. In 44 comparisons (2 groups of children X 22 gingival units) the SBI was significantly more sensitive than the GI 27 times (61.4%), the GI was more sensitive 6 times (13.6%) and in 11 comparisons (25%) no significant difference between the indices could be found. When the findings for gingival units in the maxilla and in the mandible were examined separately, the GI was more sensitive than the SBI 5 times in the maxilla (2 groups X 11 gingival units = 22 comparisons) and once in the mandible. These were in all cases marginal (M) gingival units. On the other hand, for all papillary units, whether in maxilla or mandible, the SBI was always significantly more sensitive.