TABLE 1.

Relationship between PD and CKD in clinical assessment.

Study authors/published time	Sample number	Research parameters	Type of study	Result	Conclusion
Han et al. (2013)	15,729 Korean adults from the Korean National Health and Nutritional Examination Surveys IV and V	eGFR, proteinuria, and hematuria	Cross-sectional study	1. PD patients: decreased eGFR, 4.07 (3.11–5.33); proteinuria, 2.12 (1.48–3.05); and hematuria, 1.25 (1.13–1.39, all P < 0.001) 2. Periodontitis was a significant predictor of decreased eGFR independent of all covariates [1.39 (1.03–1.89), P = 0.034] 3. Periodontitis was significantly correlated with hematuria [1.29 (1.15–1.46), P < 0.001]	The correlation between periodontitis and CKD markers Periodontitis was significantly correlated with hematuria.
Kim et al. (2017)	Low: 37 Moderate: 35 High: 35	PI, GI, PD, CAL	Cross-sectional study	1. Between groups— (χ2, p > 0.05) 2. Patients with severe periodontal disease: chance of high risk ↑ (odds ratio: 104.5; 95% CI: 10.7–1017.2; p < 0.0001).	1. Most of patients with chronic renal disease presented periodontal disease. 2. Patients with advanced periodontal disease had greater chance of high periodontal risk
de Souza et al. (2014)	CP: 73 (treated: 43; untreated: 30) No CP: 49	GI, PI, CI, PD, CAL, DMF-T, CRP, sCa, sP, sAP, serum albumin	Cohort study	1. CP vs. no CP: risk of death ↑ (hazard ratio 2.65 [95% confidence interval 1.06 to 6.59]; P = 0.036) 2. CP vs. a lesser extent for treated: (2.36 [1.01 to 5.59]; P = 0.047)	1. Poor oral health, including CP, is a common finding in patients undergoing HD. 2. CP patients had a higher risk of death.
Zhao et al. (2014)	HD patients: 102 Trauma patients: 204	AL, CPI, BL	Case control study	1. The CPI and AL showed statistical differences (P < 0.001). 2. BL: HD ↑ (P < 0.01), except the disto-buccal one (P < 0.05). 3. Furcation defect: HD was nearly double that of the controls (P < 0.001)	1. Periodontitis and periodontal BL were significantly more severe in the Chinese patients undergoing HD. 2. Periodontal disease may affect bone loss parameters in HD patients.
Sharma et al. (2016)	CKD: 861 Non-CKD: 12923	eGFR, HDL, CAL, total serum cholesterol, BOP, PPD, C-PPD	Cohort study	The 10-year all-cause mortality rate for individuals with CKD increased from 32% (95% CI: 29–35%) to 41% (36–47%) with the addition of periodontitis	Periodontitis is associated with mortality in patients with CKD
Kshirsagar et al. (2009)	Mild or no periodontal Disease: 100 Moderate-to-severe Disease: 68	Serum albumin, CRP, sCa, sP, sPTH, serum total cholesterol, serum ferritin	Retrospective cohort study	1. Moderate-to-severe disease was significantly associated with death from CVD causes, HR (95% confidence interval) 5.3 (1.5–18.9), P = 0.01 2. Adjustment for a variety of co-variables did not diminish the strength of this association. HR 5.0 (95% confidence interval, 1.2–19.1; P = 0.02).	Periodontitis could affect the progression of CVD.
Almeida et al. (2017)	CKD and severe CP: 26	PI, BOP, CAL, PPD, eGFR, triglycerides, total cholesterol, albumin and ADMA levels	Clinical trial	The median values (25%; 75% percentiles) of eGFR improve from 34.6 (27; 44.7) mL/min/1.73 m2 on baseline to 37.6 (29.7; 57) mL/min/1.73 m2 on day 90, and to 37.6 (28.6; 56) mL/min/1.73 m2 (p < 0.05) on day 180	CKD is associated with periodontitis. Periodontal treatment may be beneficial to the course of CKD.
Artese et al. (2010)	Predialysis patients: 21 CP without clinical evidence of kidney disease: 19	GB, VP, SUP, BOP, PD, AL, GFR, creatinine, calculus index	Clinical trial	Periodontal treatment had a statistically significant positive effect on the glomerular filtration rate of each individual (group 1, p = 0.04; group 2, p = 0.002)	Periodontal parameters improved after treatment. CKD predialysis patients show a good response to non-surgical periodontal treatment.
Graziani et al. (2010)	GCP systemically healthy subjects: 20	GFR, CRP, SAA, D-dimer, fibrinogen	Clinical trial	1. Cystatin C: ↓ from baseline to the end of the trial (p < 0.01). 2. CRP and SAA: ↑ (p < 0.001 versus baseline), while D-dimer (p < 0.05) and fibrinogen (p < 0.01) showed mild variations.	GFR may be positively affected by PT.
Lee et al. (2014)	Treatment: 35456 No treatment: 141824	Sex, age, and comorbidities	Retrospective cohort study	The incidence of ESRD in the treatment cohort: ↓ (4.66 versus 7.38 per 10,000 person-years), with an adjusted HR of 0.59 (95% CI = 0.46 to 0.75)	Surgical periodontal treatment reduced ESRD risk
Oyetola et al. (2015)	CRF and ESRD: 90 Controls: 90	GFR	Case control study	1. Oral lesions were present in 86 out of 90 (96.5%) CKD patients compared with 15 out of 90 (16.7%) controls (p < 0.001). 2. The mean GFR in subjects with oral lesions: ↓ p < 0.001.	1. Oral lesions are much more common in CKD patients. 2. The presence of oral lesions was positively associated with a decrease in GFR.
Honarmand et al. (2017)	HD: 30 Controls: 30	Saliva urea and calcium levels and pH values	Cross-sectional study	The mean salivary urea level (p = 0.0001) and pH value (p = 0.042) in the patient group: ↑	CKD patients display increased serum urea concentrations and elevated pH in the oral cavity

GI, gingival index; PI, plaque index; PPD, probing pocket depth; BOP, bleeding on probing; CAL, clinical attachment level; DMF-T, decayed, missing, and filled teeth index; AL, attachment loss; CRP, C-reactive protein; PD, probing depth; CI, calculus index; sCa, serum calcium; sP, serum phosphorus; sAP, serum alkaline phosphatase; BL, bone loss; CPI, community periodontal index; C-PPD, cumulative periodontal probing depth; PPD, periodontal probing depth; eGFR, estimated glomerular filtration rate; HDL, high-density lipoprotein; sPTH, serum parathyroid hormone; ADMA, asymmetric dimethylarginine; VP, visible plaque index; GB, gingival bleeding index; SUP, suppuration; SAA, serum amyloid A; GFR, glomerular filtration rate; HD, hemodialysis; GCP, generalized chronic periodontitis; CP, chronic periodontitis; CKD, chronic kidney disease; CRF, chronic renal failure; ESRD, end stage renal disease; CVD, cardiovascular disease.