Table 1 Clinical and demographic characteristics of the study population

Age (range, median)

56–61, 59

24–32, 26

15–19, 17

Gender (% male)

72

52

54

Ethnicity (number of Caucasian to African American to Hispanic to Asian)

17:5:2:1

8:5:3:2

0:17:0:0

% bone loss/age at most affected site (range)

0.73–3.1

0.86–3.57

0.9–2.8

Probe depth at deepest site (range, median)

6–9, 6

5–8, 6

7–10, 7

Number of teeth with furcation involvement (range, median)

0–6, 2

1–3, 2

1–2, 2

Clinical attachment loss at deepest site (range, median)

7–10, 7

6–9, 7

7–10, 8

Bleeding on probing (% sites) (range, median)

20–100, 80

20–80, 65

10–40,

Molar-Incisor pattern (number of subjects)

0

0

17

Mean plaque index (Loe and Silness) (range)

1.2–2.3

1.1–2.1

0.5–0.7

Mean gingival index (Loe and Silness) (range)

1.3–2.5

0.9–2.2

0.6–0.9

Number of individuals with tooth loss

6

3

3

Number of individuals with known history of tooth loss due to periodontitis

5

2

3

Number of teeth lost/individual (excluding third molars, orthodontic reasons and congenitally missing) (range)

0–5

0–3

0–1

Number of teeth known to be lost to periodontitis/individual (range)

0–2

0–3

1