Meta-analysis of the association between chronic periodontitis and chronic kidney disease

Table 3 Basic characteristics of pocket probing depth (mm) level differences between chronic kidney disease patients and non-chronic kidney disease population

Ref.	Research locaiton	Research type	Sample size (CKD/non-CKD)	Average PPD (mm, CKD/non-CKD)
Garcez et al[20]	United States of America	Cross-sectional study	80/80	0.65 ± 0.75/0.56 ± 0.79
Tollefsen et al[26]	Norway	Cross-sectional study	12/12	2.61 ± 0.85/2.60 ± 0.42
Frankenthal et al[22]	Israel	Cross-sectional study	35/35	2.92 ± 0.14/2.90 ± 0.12
Marakoglu et al[27]	Türkiye	Cross-sectional study	36/36	1.80 ± 0.6/1.8 ± 0.8
Bayraktar et al[28]	Türkiye	Cross-sectional study	116/61	1.89 ± 0.48/1.94 ± 0.62
Cengiz et al[23]	Türkiye	Cross-sectional study	68/41	2.3 ± 0.6/1.6 ± 0.6
Limeres et al[24]	Portugal	Cross-sectional study	44/44	1.55 ± 0.98/0.81 ± 0.94
Camacho-Alonso et al[25]	Spain	Cross-sectional study	91/118	2.33 ± 1.07/1.76 ± 0.71

CKD: Chronic kidney disease; PPD: pocket probing depth