Table 2 Summary of included cohort studies

Remaining Teeth

Suzuki [42]

2021

Japan

1 year

1,017,758

50–74

Sum of medical expenditure and pharmacy expenditure

28 or more

25–27

20–24

15–19

10–14

5–9

1–4

Referent group

Difference in the medians for public health expenditure in relation to number of teeth was smaller than that for the means.

Patients with DM and a lower number of teeth incurred higher medical expenditure.

Ruokonen, [43] 2017,

Finland

13 years

144

≥ 55^†

< 55^†

Mortality due to chronic kidney disease

≤ 25

> 25

Referent group

HR 0.95 (0.92,0.98)

Participants with chronic kidney disease with > 25 remaining teeth had significantly lower hazard of mortality than those with ≤ 25 remaining teeth, after controlling for diabetic nephropathy (n = 52) vs other types of chronic kidney disease (n = 92) and age.

Demmer, [44] 2008,

U.S.A.

17 ± 4 years

9296

50 ± 19*

Diabetes incidence

24–32

18–23

8–17

1–7

Edentulous

Referent group

OR NS

NS

1.7 ^‡ (p < 0.05)

1.3 (1.00,1.70)

Missing ≥ 25 teeth was significantly associated with increased incidence of diabetes relative to those missing 0–8 teeth. Edentulous participants had 30% greater odds of developing diabetes than periodontally healthy individuals.

Missing

Teeth

Håheim, [45]

2017,

Norway

12.5 years

5323

70.4 ± 4.7*

Mortality

0 to 1

2 to 4

5 to 8

9 to 31

Edentulous

Referent group

HR 1.01 (0.73,1.39)

0.86 (0.57,1.30)

1.14 (0.79,1.66)

1.23 (0.67,2.24)

Number of teeth extracted was not a significant predictor of mortality in men with diabetes.

Liljestrand, [24]

2015,

Finland

13 years

7862

60.8 ± 8.4*

Diabetes incidence

0 to 1

2 to 4

5 to 8

9 to 31

Edentulous

Referent group

HR 1.20 (0.88,1.63)

1.36 (0.97,1.90)

1.37 (1.02,1.86)

1.56 (1.10,2.20)

Missing ≥ 9 teeth was significantly associated with increased incidence of diabetes.