Table 6 List of the included clinical studies and its main characteristics

Eskow et al. (2017) [10]

Retrospective

24

59.7 ± 9.6

k.A.

34

59

98.6 (1 year); 96.6 (2 years)

2

No controlgroup

n.d.

“Poorly controlled”; 9.55 ± 1.0%

14.2 ± 7.7 years

Ormianer et al. (2018) [11]

Retrospective

169

55.9 ± 10.474

1995–2015

104

1112

94

2

n.d.

n.d.

“Moderately controlled” < 8%; “well-controlled” up to 7%

At least 2 years

Castellanos-Cosano et al. (2019) [12]

Retrospective

346

56.12 ± 12.15

2014–2017

48

44,415

n.d.

n.d.

No controlgroup

n.d.

n.d.

n.d.

Alrabiah et al. (2019) [13]

Cross-sectional

79

Prediabetic group: 54.3 ± 3.6; nondiabetic group: 51.2 ± 2.4

n.d.

60

80

100

Prediabetes

Nondiabetic group

n.d.

Prediabetic group: 6.1[5.9–6.3]%; nondiabetic group: 4.1[4–4.8]%

Prediabetes diagnosis 5.4 ± 0.2 years

Sghaireen et al. (2020) [14]

Retrospective

257

Diabetic group: 62.41 ± 13.62y; nondiabetic group: 59.24 ± 29.36 y

2013–2016

36

742

Diabetic group: 90.18; nondiabetic group: 90.95

n.d.

HbA1c < 6.5%

n.d.

“Well controlled” 6.5–8%; no further information + L8

n.d.

Papantonopoulos et al. (2017) [15]

Cross-sectional

72

61.9 ± 11.1

2014–2015

n.d.

237

n.d.

n.d.

Nondiabetic Clusters

n.d.

n.d.

n.d.

Atarchi et al. (2020) [16]

Cross-sectional

1343

61.66 ± 12.77

2002–2017

n.d.

2323

n.d.

n.d.

Nondiabetic group

n.d.

 < 8%;“controlled diabetics”

n.d.

Alasqah et al. (2018) [17]

Cross-sectional

86

Diabetic group: 57.6 ± 5.5; nondiabetic group: 61.6 ± 4.3 y

n.d.

72

172

n.d.

2

Nondiabetic group; HbA1c 5.3 ± 0.3%

n.d.

“Well controlled” diabetes group: 4.8 ± 0.2%; nondiabetic group: 5.3 ± 0.3%

10.1 ± 3.5 years

Singh et al. (2020) [18]

Retrospective

826

n.d.

n.d.

120

1420

n.d.

n.d.

n.d.

n.d.

n.d.

n.d.

Al Zahrani et al. (2019) [19]

Prospective

67

Well controlled diabetics: 54.6 ± 9.9; poorly controlled diabetics: 53.8 ± 7.9

2009–2011

84

124

99 (7 years)

2

Poorlycontrolled diabetics

“Well controlled” diabetics: controlled by diet and anti-diabetic drugs (w or w/o insulin); “poorly controlled” diabetics: no control by diet or drugs

“Well controlled” diabetics: ≤ 6.0% “poorly controlled” diabetics: > 8.0%

Well controlled: 6.6 years; poorly controlled: 11.8 years

Erdogan et al. (2015) [20]

Prospective

24

Diabetic group: 52.5 ± 7.3; nondiabetic group: 49.5 ± 9.3

k.A.

12 (and more)

43

100

2

n.d.

All diabetic patients on active treatment (oral therapy, insuline, combination)

6.7 ± 0.3%

8.2 ± 3.5 years

Oztel et al. (2017) [21]

Retrospective

177

60.2 ± 15.1

2011–2013

36

302

95

n.d.

n.d.

n.d.

n.d.

n.d.

Gomez-Moreno et al. (2015) [22]

Prospective

67

Groups: HbA1c ≤ 6%: 60 ± 7.2; HbA1c = 6.1–8%: 59 ± 8.1; HbA1c = 8.1–10%: 62 ± 6.8; HbA1c ≥ 10.1%:64 ± 5.6

n.d.

36

67

n.d.

2

Four groups: HbA1c ≤ 6%; HbA1c = 6.1–8%; HbA1c = 8.1–10%; HbA1c ≥ 10.1%

n.d.

Four groups: HbA1c ≤ 6%; HbA1c = 6.1–8%; HbA1c = 8.1–10%; HbA1c ≥ 10.1%

n.d.

Dogan et al. (2015) [23]

Prospective

20

Diabetic group: 53.54 ± 4.01; nondiabetic group: 52.14 ± 3.93

2010–2011

7

39

n.d.

2

HbA1c 4.87 ± 0.53%

All diabetic patients: oral antidiabetics, exclusion criteria: insulin-therapy

“Well controlled”: 6.37 ± 1.28%

“At least 5 years”

Okamoto et al. (2018) [24]

Retrospective

289

Complications group: 62.8 ± 2.6; no complications group: 54.7 ± 13.1

2006–2013

0.75

298

100

n.d.

n.d.

n.d.

n.d.

n.d.

Al Amri et al. (2015) [25]

Prospective

91

HbA1c ≤ 6%: 48.5(45–52); HbA1c = 6.1–8%: 50.1(46–55); HbA1c = 8.1–10%: 50.5(45–59);

k.A.

24

n.d.

n.d.

2

HbA1c < 6%

k.A.

Three groups: HbA1c ≤ 6% (controls included); HbA1c = 6.1–8%; HbA1c = 8.1–10%

n.d.

de Araujo Nobre et al. (2016)

Retrospective

70

59(41–80)

1999–2007

60

352

89.8; group with type 1 diabetes mellitus: 80; group with type 1 diabetes mellitus: 90.5

1 and 2

No controlgroup

“Treated”; no further information

n.d.

n.d.

Al Amri et al. (2017) [26]

Retrospective

108

Immediately loaded group: 50.6 ± 2.2; conventional loading group 51.8 ± 1.7

n.d.

24

108

100

2

No controlgroup

n.d.

No initial HbA1c; At 12- and 24-month follow-up, the mean HbA1c levels in group 1 (immediately loading) and 2 (conventional loading) were 5.4%(4.8–5.5%) and 5.1%(4.7–5.4%) and 5.1%(4.7–5.2%) and 4.9%(4.5–5.2%)

Immediately loaded group: 9.2 ± 2.4 years; conventional loaded 8.5 ± 0.4 years

Al Amri et al. (2017) [27]

Prospective

45

Diabetic group: 42.4(40–46); nondiabetic group: 41.8(39–44)

n.d.

24

45

n.d.

2

HbA1c < 4.5% (visually, boxplot)

Antihyperglycemic drugs, dietary control

“Well controlled”: no exact data given, but visually (boxplots) the baseline HbA1c is significantly higher in the diabetic group (visually < 7%) than in nondiabetic control group (visually < 4.5%)

14.5 ± 0.7 months

Soh et al. (2020) [28]

Retrospective

89

n.d.

2019–2020

3

n.d.

n.d.

n.d.

n.d.

n.d.

n.d.

n.d.

Mohanty et al. (2018) [29]

Cross-sectional

208

n.d.

n.d.

96–120

425

Diabetic group: 70.7, periodontitis group: 83.3, smokers group: 80.9, bruxism group:86.3

n.d.

n.d.

n.d.

n.d.

n.d.

Aguilar-Salvatierra et al. (2016) [30]

Prospective

85

Group 1: 57 ± 3.8; group 2: 57 ± 3.8; group 3: 61 ± 1.9

n.d.

48

85

Group 1: 100; group 2: n.d.; group 3: 86.3

2

Three groups: HbA1c ≤ 6%; HbA1c = 6.1–8%; HbA1c = 8.1–10%

Oral hypoglycemic agents with similar doses

Three groups: HbA1c ≤ 6%; HbA1c = 6.1–8%; HbA1c = 8.1–10%

n.d.

Rekawek et al. (2021) [31]

Retrospective

286

n.d.

2006–2012

60 (and more)

748

n.d.

n.d.

HbA1c < 8%

k.A.

 > 8% “uncontrolled diabetes”

n.d.

Jagadeesh et al. (2020) [32]

Retrospective

342

n.d.

n.d.

24

580

87.5

n.d.

n.d.

n.d.

n.d.

n.d.

Kandasamy et al. (2018) [33]

Retrospective

200

47.5

n.d.

96–180

650

n.d.

n.d.

n.d.

n.d.

n.d.

n.d.

Pedro et al. (2017) [34]

Prospective

23

71.05(65–80)

2009–2013

48

57

n.d.

n.d.

n.d.

n.d.

n.d.

n.d.

Yadav et al. (2018) [35]

RCT

88

Flap group: 54.35 ± 14.51; Flapless group: 57.82 ± 13.99

2013–2015

30

88

n.d.

2

n.d.

“Controlled” (under medication)

Inclusion criterion: HbA1c less than 7%; Flap group: 6.59 ± 0.42%; Flapless group: 6.75 ± 0.30%

Flap group: 6.55 ± 4.01 years; Flapless group: 6.91 ± 3.86 years

Khan et al. (2016) [36]

Retrospective

83

n.d.

2010–2015

n.d.

220

86,8

n.d.

n.d.

n.d.

n.d.

n.d.

French et al. (2021) [37]

Retrospective

4247

53.8 ± 13.5

1995–2019

54

10,871

98.9 (3 years), 98.5 (5 years), 96.8 (10 years), and 94.0 (15 years)

Mellitus

n.d.

n.d.

n.d.

n.d.

Alberti et al. (2020) [38]

Retrospective

204

57.3 ± 13.7

2005–2018

68

929

Diabetic group: 96.51, nondiabetic group: 94.74

1 and 2

n.d.

Diet:5, Metformin:7, Insuline:3, Sulfonylureas:1, Metformin + Sulfonylureas:3, Metformine + Pioglitazone + Glicazide:1

6.40 ± 0.36% (isurgery)

n.d.

Krebs et al. (2019) [39]

Retrospective

106

70.9(45–91)

1991–1997

227

274

n.d.

Mellitus

n.d.

n.d.

n.d.

n.d.

Dalago et al. (2017) [40]

Retrospective

183

59.3

1998–2012

68

938

98.3

n.d.

n.d.

n.d.

n.d.

n.d.

De Araújo Nobre et al. (2017) [41]

Prospective

22,009

48.5 ± 15.6

2012–2015

24

n.d.

n.d.

n.d.

n.d.

n.d.

n.d.

n.d.

Mayta-Tovalino et al. 2019) [42]

Retrospective

431

n.d.

2006–2017

132

1279

82.02

n.d.

n.d.

n.d.

n.d.

n.d.

Kissa et al. (2020) [43]

Cross-sectional

145

58.3

04/2017–12/2017

77

642

n.d.

Mellitus

n.d.

n.d.

n.d.

n.d.

Krennmair et al. (2018) [44]

Prospective

85

56.7 ± 11.2

2007–2009

60

295

99

2

n.d.

n.d.

 ≤ 7,5% controlled (> 7.5% = Exclusion criteria)

n.d.

Al-Sowygh et al. (2018) [45]

Cross-sectional

93

Three diabetic groups; group 1: 51.5(46–57), group 2: 53.7 (42–56), group 3: 55.9 (49–59); nondiabetic group: 50.1(41–53)

n.d.

n.d.

148

n.d.

2

Non-diabetic individuals with HbA1c < 6% (mean:5.8%)

n.d.

Group 1: HbA1c 6.1–8%(mean:6.7%); group 2: HbA1c 8.1–10%(mean:9.2); group 3: HbA1c > 10%(mean:11.4);

Group 1: 10.7(7–11.2) years, group 2: 9.4(8–10.6) years, group 3: 12.6(9.9–14.1) years

Corbella et al. (2020) [46]

Retrospective

112

57.3 ± 13.7

2004–2019

52

344

91.69 (12 years)

Mellitus

No controlgroup

n.d.

n.d.

n.d.

Al Amri et al. (2017) [47]

Prospective

24

Prediabetic group: 44.5(41–49); nondiabetic group: 43.3(39–47)

n.d.

12

24

100

Prediabetes

HbA1c: (baseline:) 4.4 ± 0.2%

n.d.

Baseline: Prediabetic group:6.1 ± 0.4; nondiabetic group:4.4 ± 0.2; follow-up values given

n.d.

Weinstein et al. (2020) [48]

Cross-sectional

248

63.4 (women); 62.5 (men)

Unclear

5

1162

n.d.

n.d.

n.d.

n.d.

n.d.

n.d.