Table 3.

Clinical studies.

Treatment	Study Design and Population	Methods	Results	Authors, Year	Ref.
The experimental treatment consisted of 90 mg supplement based on blueberry and red fruit rich in oligomeric proanthocyanidins (OPCs) (equivalent to 36 mg OPCs-oligomeric proanthocyanidins) and 120 mg of vitamin C	A prospective, double-blind, randomized, controlled clinical trial in the gingivitis prevention. 20 healthy volunteers took the experimental or placebo treatment for 21 days. The pill was maintained in the mouth until complete dissolution.	Two evaluation visits were performed—after 14 and 21 days. During clinical examination Silness and Löe index, the gingival bleeding index, the Turesky plaque index, the inflammatory crevicular fluid study (IL6), and changes in the brightness of the gingiva were evaluated.	The Silness and Löe gingival index was higher in the control group than in the experimental group. The bleeding was lower in the experimental group compared to the control group. In contrast to the above results, the amount of dental plaque was slightly higher (33%) in the experimental group versus in the control group. No significant differences between the study group and the control group were seen in brightness of the gingiva. Statistically significant differences in level of IL-6 were found at the baseline between the experimental group and the control group and in the subsequent visits. However, in experimental group level of IL-6 was lower.	Díaz Sánchez et al., 2017	[59]
Thermo-reversible sustained-release system incorporated with green tea extract	A controlled, split-mouth single-evaluator masked study was conducted to evaluate the effect of green tea extract as a sustained-release system in patients with chronic periodontitis (CP). 30 patients, each with 2 sites (test and control) having probing depths (PDs) of ≥4 mm, were selected. Green tea and placebo gels were placed at test and control sites as an adjunct to Phase 1 periodontal therapy.	Assessment of gingival index (GI), pocket depth (PD), and relative clinical attachment levels (rCALs) was done at baseline and at 4 weeks.	When the comparison of means of GI, PD, and rCAL was done between baseline values and at the end of 4 weeks within the test group, and control group all the parameters were lowered and statistically highly significant. The test group showed significantly better results when compared with controls. Adjunctive local drug therapy with thermo-reversible green tea gel has revealed to reduce pockets and inflammation during the 4 weeks of the clinical trial in patients with CP.	Chava and Vedula 2013	[60]
Hydroxypropylcellulose strips containing green tea catechin (Taiyo Kagaku, Mie, Yokkaichi, Japan)	6 volunteers with advanced periodontitis, but with no other systemic disorders. From each volunteer two pockets were selected: one for administration of the test agent and the other for placebo. Strips were applied in pockets in patients once a week for 8 weeks. The subjects were divided randomly into the scaled group (3 subjects) non-scaled group (3 subjects) were applied in pockets in patients.	The clinical PD, enzymatic (peptidase activities) and microbiological effects (the proportion of black-pigmented, Gram-negative anaerobic rods (BPR) of the catechin) were determined.	The PD and the BPR were decreased in the catechin group with mechanical treatment at week 8 compared to baseline. The peptidase activities in the gingival fluid were maintained at lower levels during the experimental period in the test sites with catechin, while it reached 70% of that at baseline in the placebo sites.	Hirsawa et al., 2002	[61]