Objective: Oral and periodontal infection load need to be treated in the predialysis stage among chronic kidney disease (CKD) patients in order to avoid later complications in dialysis or transplantation. Periodontal health was studied by specifically comparing diabetic nephropathy patients with those with other kidney disease. Method and Materials: This descriptive retrospective study comprised 144 predialysis patients (47 women), aged 23 to 83 years, examined at the Helsinki University Hospital, Finland. Of them, 52 (36%) had diabetic nephropathy. Oral and general health data, Periodontal Inflammatory Burden Index (PIBI), and Total Dental Index (TDI) were recorded from hospital records. Results were analyzed with cross tabulation, Pearson chi-square test, and binary logistic regression with Wald test. Results: Of the diabetic nephropathy patients 39%, and of those with high A1C values 36%, respectively, had two or more sites with probing depths ≥ 6 mm compared with 19% in the other CKD group, and 18% of those with lower A1C values. TDI scores were high among 55% of the diabetic nephropathy patients. A1C values ≥ 6.5% associated with moderate periodontitis in 67%, and elevated PIBI in 62%. Conclusion: High A1C values associated with high oral infection burden indices. Diabetic nephropathy patients had more often high TDI scores and deep periodontal pockets compared with the other CKD patients. Keywords: chronic kidney disease (CKD), diabetes, glycosylated hemoglobin, periodontal disease, predialysis