A pilot RCT to assess changes in clinical parameters and localized inflammation following 13 months of fish oil supplementation in combination with non-surgical periodontal treatment

OBJECTIVES: To evaluate the effects of long chain omega‐3 polyunsaturated fatty acid (LCn3PUFA) rich fish oil (FO) supplementation for 13 months as an adjunct to non‐surgical treatment for advanced chronic periodontitis in a randomized, controlled parallel trial. METHODS: Thirty three participants (10M/23F, mean age 52 ± 10 years) were randomized to consume six 1g capsules/day containing either FO (1884mg LCn3PUFA; n=23) or soy oil (n=10) and were assessed at baseline and after 4, 7, 10 and 13 months for probing pocket depth (PPD), clinical attachment (CAL) and inflammatory mediators in the gingival crevicular fluid from the two deepest sites. At baseline, 4 and 13 months the percentage LCn3PUFA content of erythrocytes in fasting blood was assessed to check compliance. RESULTS: Good compliance to supplementation was evident: erythrocyte LCn3PUFA content increased 3.2% (p< 0.001) over 13 months in the FO group compared with no change (‐0.1%) in the placebo group. A Poisson Generalized Estimating Equation model was used to compare between groups across time, adjusting for patient ID and tooth position. Significant reductions in mean PPD and CAL were observed in both groups with group by time interactions indicating the placebo group had less PPD at 10 months compared with FO and less CAL at 4 and 13 months compared with FO. The frequency of deep sites declined significantly from baseline to 13 months in both groups (PPD>=5mm: 19 to 4% FO vs 18 to 2% placebo p<0.05; CAL>=6mm: 18 to 4% FO vs 12 to 0.5% placebo, p<0.05). No changes were observed between groups in localized inflammatory mediators including C‐reactive protein, interleukin‐1 beta and tumour necrosis factor‐alpha. Changes in clinical measures were not associated with changes in localized inflammatory mediators. CONCLUSIONS: Whilst periodontal treatment was effective across all participants overall, fish oil did not provide an added benefit.