Modern Research in Inflammation Vol. 2 No. 2 (2013), Article ID: 31112.
Effect of Morinda citrifolia L. fruit juice on gingivitis/periodontitis.
Glang J, Falk W, Westendorf J.

In a pilot clinical study, the papillae-bleeding-index was significantly reduced in gingivitis/periodontitis patients who used noni juice as a twice-daily mouth wash for 4-weeks, when compared to a control group.  Noni juice also reduced gingival inflammation. (original abstract available at https://www.scirp.org/journal/PaperInformation.aspx?paperID=31112).