An interventional study of St. John's Wort Oil and Chlorhexidine in Gingivitis and Maxillary Transversal Deficiency, sponsored by Yuzuncu Yil University. Completed at 1 site in Turkey (Türkiye). Open to participants aged 11 Years to 16 Years. Per ClinicalTrials.gov, last updated 2026-10-20.
Sponsored by Yuzuncu Yil University · Not applicable, Interventional, and Treatment
The goal of this clinical trial was to learn whether St. John's wort (Hypericum perforatum) oil helps gum healing in children and adolescents aged 11 to 16 years after treatment with a rapid maxillary expansion appliance. This appliance widens the upper jaw, but it covers a large part of the palate and makes cleaning difficult, which can cause gum redness, bleeding, swelling and pain after the appliance is removed.
The main questions it aimed to answer were:
Does St. John's wort oil improve gum health after the appliance is removed? Does it reduce pain in the days after appliance removal?
Researchers compared St. John's wort oil with chlorhexidine mouthwash, a commonly used oral antiseptic, and with a control group that used no antiseptic product.
Participants:
Were randomly assigned to one of three groups after removal of the expansion appliance Used St. John's wort oil as a mouthrinse or chlorhexidine three times a day for 7 days, or used no product (control group) Had their gums examined before the appliance was placed, when it was removed, and 7, 14 and 30 days later Recorded their pain level on a 0-10 scale on several days after appliance removal
609 studies on the registry are indexed under Gingivitis; 107 are open to participants now.
This study's enrollment of 60 is close to the median of 63 across 494 interventional studies indexed under Gingivitis.
Browse Gingivitis studies →Yuzuncu Yil University is the lead sponsor of 75 studies on the registry; 19 are open to participants now.
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Exclusion Criteria:
Participants rinsed with St. John's wort (Hypericum perforatum) oil three times daily for 7 days after removal of the rapid maxillary expansion appliance.
Other: St. John's Wort Oil
Participants rinsed with chlorhexidine mouthwash three times daily for 7 days after removal of the rapid maxillary expansion appliance.
Drug: Chlorhexidine
Participants received no mouthwash after removal of the rapid maxillary expansion appliance.
St. John's wort (Hypericum perforatum) oil was used as a mouthrinse three times daily for 7 days, starting after removal of the rapid maxillary expansion appliance. The product was dispensed in an identical, unlabeled bottle.
Chlorhexidine gluconate mouthwash was used as a mouthrinse three times daily for 7 days, starting after removal of the rapid maxillary expansion appliance. The product was dispensed in an identical, unlabeled bottle.
Gingival Index (Löe & Silness)
Gingival inflammation was assessed using the Löe and Silness gingival index (score 0-3; 0 = normal gingiva, 3 = severe inflammation with tendency to spontaneous bleeding). Higher scores indicate worse gingival health.
Time frame: Before appliance placement (baseline), at appliance removal, and 7, 14 and 30 days after appliance removal
Plaque Index (Silness & Löe)
Plaque accumulation was assessed using the Silness and Löe plaque index (score 0-3; 0 = no plaque, 3 = abundant plaque). Higher scores indicate more plaque accumulation.
Time frame: Before appliance placement (baseline), at appliance removal, and 7, 14 and 30 days after appliance removal
Bleeding on Probing
Percentage of sites showing bleeding within 15 seconds after gentle probing. Higher percentages indicate more gingival inflammation.
Time frame: Before appliance placement (baseline), at appliance removal, and 7, 14 and 30 days after appliance removal
Pain Intensity (Visual Analogue Scale)
Pain was self-reported by participants on a 10 cm visual analogue scale (0 = no pain, 10 = worst imaginable pain). Higher scores indicate more pain.
Time frame: Days 2, 4, 5 and 6 after appliance removal
Plan to share: No — Individual participant data will not be made publicly available because the participants were minors and the informed consent forms did not include permission for public data sharing. De-identified data are available from the corresponding author upon reasonable request.
No publications or documents are linked to this record.
Ran from Jun 2019 to primary completion in Nov 2020, 17 months.
Of 203 non-industry interventional studies with no phase under Gingivitis, half reached primary completion within 9 months of starting (the median), counting those still running; a quarter within 4 and three quarters within 19. This study's 17 months is above that.
Counting every sponsor, half of 255 studies reached it within 7 months; a quarter within 3 and three quarters within 16.
How these figures are worked out, and which studies are left out of them.
From the registry record's own update history. This site started tracking changes on Sep 25, 2026; for anything earlier, see the record history on ClinicalTrials.gov ↗
This study is completed, as verified in Oct 2026. You cannot join it, but the record below documents what was studied.
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Yuzuncu Yil University