The aim of this study was to measure the occurrence of severe chronic periodontitis in a group of Colombian type 2 diabetes patients. A group of type 2 diabetic patients regularly attending a diabetes program was selected according to specific criteria. Demographic, medical and periodontal variables were recorded. A randomized half-mouth examination was performed, including plaque index, bleeding on probing, pocket depth and clinical attachment level. They were compared to a group of individuals without diabetes, based on different criteria; the first was the presence of > or = 2 interproximal sites with CAL > or = 6 mm, and > or = 1 interproximal sites with PD > or = 5 mm; the second was presence of > or = 50% percentage of bleeding on probing, and > or = 20% sites showing PD > or = 4 mm. The effect of metabolic control was analyzed. Results were tested through Chi-square, Mann-Whitney, Kruskal-Wallis and Pearson correlation tests. Seventy-two subjects with type 2 diabetes were compared to 39 subjects without diabetes of a similar age. Diabetic subjects had a fair degree of metabolic control, HbA1c 7.94% (1.60). Occurrence of severe chronic periodontitis was similar for both groups when using diagnostic criteria based on CAL levels, 22.22%, but was greater for subjects with diabetes when using criteria based on periodontal inflammation, 23.07% versus 5.12%. Degree of metabolic control had a relation to periodontal parameters. Colombian type 2 diabetes subjects demonstrated poorer periodontal conditions than non-diabetic individuals.