We aimed to investigate the impact of nonsurgical periodontal treatment combined with one-year dietary supplementation with omega (ω)-3 on the serum levels of eicosapentaenoic acid (EPA), docosahexaenoic acid (DHA), docosapentaenoic acid (DPA), and arachidonic acid (AA).

Fifteen patients with chronic generalized periodontitis were treated with scaling and root planing. The test group consisted of seven patients (43.1±6.0 years) supplemented with ω-3, consisting of EPA plus DHA, three capsules, each of 300 mg of ω-3 (180-mg EPA/120-mg DHA), for 12 months. The control group was composed of eight patients (46.1±11.6 years) that took a placebo capsule for 12 months. The periodontal examination and the serum levels of DPA, EPA, DHA, and AA were performed at baseline (T0), and 4 (T1), and 12 (T2) months after therapy.

In the test group, AA and DPA levels had been reduced significantly at T1 ( P <0.05). AA and EPA levels had been increased significantly at T2 ( P <0.05). The ΔEPA was significantly higher in the test compared to the placebo group at T2-T0 ( P =0.02). The AA/EPA had decreased significantly at T1 and T2 relative to baseline ( P <0.05).

Nonsurgical periodontal treatment combined with ω-3 supplementation significantly increased the EPA levels and decreased the AA/EPA ratio in serum after one year follow-up. However, no effect on the clinical outcome of periodontal therapy was observed.