Table 1 Descriptive information in relative frequencies, mean, and standard deviation (SD) of the study population for the three groups healthy participants (H), caries patients (C), and periodontitis patients (P)

Age range

25.4

(18–57)

6.9

31.5

(18–71)

10.2

54.8 (26–76)

12.4

Gender [%]

 Female

60.3

–

31.1

–

41.8

-

 Male

39.7

–

68.9

–

58.2

-

Body mass index

21.7

2.6

25.2

6.6

26.5

4.3

Social status [%]

 Employees without vocational training

1.6

22.0

9.8

 Employees with completed vocational training

9.8

30.5

68.6

 Academic

88.6

47.5

21.6

Dental visits [year]

1.5

0.6

1.4

1.8

1.4

1.1

Number of brush replacements [year]

5.3

2.9

6.1

4.9

6.1

3.2

Use of chlorhexidine [%]

 Yes

6

5

17

 No

94

95

83

Sugar consumption per day [%]

 Never

5

3

9

 Once daily

25

9

28

 Several times daily

70

88

63

Use of probiotics [%]

 Yes

5

7

8

 No

95

93

92

Smoking status [%]

 Non-smoker

88

61

60

 Former smoker

5

3

15

 Smoker

7

36

25

Antibiotics during the last 12 months [%]

 Yes

17

15

19

 No

83

85

81

Gingiva bleeding index [%]

8.2

9.8

18.9

22.7

24.2

17.5

Bleeding on probing [%]

8.6

9.4

18.2

19.6

41.7

22.2

DMF-T index [n]

 Decayed teeth (D)

0

0

5.4

4.3

0

0

 Missing teeth (M)

0

0

1.4

2.4

3.8

4.1

 Filled teeth (F)

0

0

7.2

4.1

11.0

5.5

 Sum (DMF-T)

0

0

14.1

5.1

14.1

6.2

Saliva pH category [%]

 Acidic (pH-value 5.0–5.9)

0

8

4

 Moderate (pH-value 6.0–6.7)

17

38

22

 Neutral (pH-value 6.8–7.8)

83

54

74

Saliva flow rate [%]

 Low (< 0.7 ml/min)

0

2

2

 Moderate (0.7–1.0 ml/min)

7

10

11

 High (> 1.0 ml/min)

93

88

87

Periodontal and gingival status [%]

Periodontal and gingival health

12.9

5.0

–

Localized gingivitis

80.6

71.7

–

Generalized gingivitis

6.5

23.3

–

Generalized moderate, localized severe chronic periodontitis

–

–

92.3

Generalized severe chronic periodontitis

–

–

7.2