A Phase 2 interventional study of 0.2% Thymus vulgaris mouthwash and Chlorhexidine 0,12% in Plaque-Induced Gingivitis, sponsored by University of Sulaimani. Not yet recruiting at 1 site in Iraq. Open to participants aged 18 Years to 45 Years. Per ClinicalTrials.gov, last updated 2026-11-02.
Sponsored by University of Sulaimani · Phase 2, Interventional, and Treatment
The goal of this clinical trial is to determine whether a mouthwash made from thyme (Thymus vulgaris) helps improve gum health in people with plaque-induced gingivitis. The mouthwash will be compared with chlorhexidine mouthwash and a placebo (a mouthwash without the active ingredient being tested).
The main questions this study aims to answer are:
Does Thymus vulgaris mouthwash improve gum health and reduce plaque accumulation and gingival bleeding?
Does it change salivary levels of substances associated with gum inflammation and tissue damage?
What side effects do participants experience, and how do they rate their experience with the mouthwash?
Participants will be randomly assigned to one of three groups: 0.2% Thymus vulgaris mouthwash, 0.12% chlorhexidine mouthwash, or placebo. They will:
Rinse with 10 mL of their assigned mouthwash twice daily for 1 minute per use.
Have their gum health assessed at the beginning of the study, after 2 weeks, and after 1 month.
Provide saliva samples at each visit for laboratory testing.
Report any side effects and share their experience with the assigned mouthwash.
To help ensure a fair comparison, the mouthwashes will be provided in identical containers with coded labels. Neither the participants nor the examiner will know which mouthwash each participant receives until the study is completed and the group codes are revealed according to the study's blinding procedures.
For the clinical part of the study, participants will be recruited from the clinics of the Periodontics Department, College of Dentistry, University of Sulaimani, from Sunday to Wednesday, between 9:00 AM and 12:00 PM.
At the first visit, a case sheet will be completed to document each participant's name, age, sex, and medical and dental history. Unstimulated saliva will be collected to assess interleukin-1 beta (IL-1β) and matrix metalloproteinase-8 (MMP-8) concentrations. In addition, the clinical parameters, including the Plaque Index (PLI), Bleeding on Probing (BOP), and Gingival Index (GI), will be assessed.
Each participant will be randomly assigned to one of three mouthwash groups: (1) a 0.12% chlorhexidine (CHX) mouthwash (Lacer Perioxidin, Lacer®, Barcelona, Spain), serving as the positive control; (2) a 0.2% Thymus vulgaris (TV) mouthwash, serving as the test intervention; or (3) a placebo mouthwash containing the same excipients as the test mouthwash but without Thymus vulgaris essential oil.
Participants will be instructed to rinse with 10 mL of their assigned mouthwash twice daily for 1 minute per use, 30 minutes after toothbrushing. They will also be instructed to refrain from eating and drinking for 30 minutes after using the mouthwash.
To standardize oral hygiene practices, all participants will be provided with the same soft-bristled toothbrush (TePe® Select Soft, TePe®, Sweden) and fluoride-containing toothpaste (Crest® Pro-Health, Crest®, USA). Each participant will receive a detailed instruction manual explaining how to use the assigned mouthwash.
Two weeks after the initial visit, participants will return for an assessment of adherence to mouthwash use and any potential side effects associated with the assigned mouthwash. The clinical parameters (PLI, BOP, and GI) will be reassessed, and another unstimulated saliva sample will be collected.
One month after the initial visit, the clinical parameters will be reassessed, and another unstimulated saliva sample will be collected for immunological and biochemical assessment. Participants will also be asked to complete a Visual Analogue Scale (VAS) questionnaire to provide feedback on their experience with the assigned mouthwash.
To maintain blinding, all mouthwashes will be dispensed in identical, opaque containers labeled with randomly assigned letters (A, B, or C) by a third party who is not involved in the clinical trial. This procedure is intended to maintain a double-blind design in which both participants and the clinical examiner remain unaware of the assigned intervention throughout the study. The group codes will be revealed only after completion of the trial, in accordance with the study's blinding and data-analysis procedures.
631 studies on the registry are indexed under Gingivitis; 107 are open to participants now.
This study's planned enrollment of 60 is close to the median of 66 across 507 interventional studies indexed under Gingivitis.
Browse Gingivitis studies →University of Sulaimani is the lead sponsor of 18 studies on the registry; 4 are open to participants now.
Counted across the registry records on this site, refreshed daily.
The criteria were revised on the registry on Nov 2, 2026. See what changed
Go through the criteria one by one — yes, no or not sure — and take the list to your doctor or the study team. Kept in this browser only.
Participants must meet all of the following criteria:
Exclusion Criteria
Individuals meeting any of the following criteria will be excluded:
5. Have received periodontal treatment or systemic antibiotics within the previous 3 months.
6. Have a known allergy or to herbal products or any ingredient in the study mouthwashes.
7. Have a known chronic systemic disease that is inconsistent with the study's eligibility requirement of ASA Physical Status I.
Underlined terms in the criteria open these too. Explained by clinicaltrials.gg, not part of the registry record. The study team decides who can take part.
The anaesthetists’ scale of health before surgery: I is healthy, II has a mild illness that is under control, III a severe one, IV a severe illness that is a constant threat to life. V and VI are used for the critically ill and for organ donors.
An allergy, or another reaction of the immune system, to a substance. “Hypersensitivity to the study drug” means a known allergic reaction to it — not every side effect a medicine can have.
ASA physical status
The anaesthetists’ scale of health before surgery: I is healthy, II has a mild illness that is under control, III a severe one, IV a severe illness that is a constant threat to life. V and VI are used for the critically ill and for organ donors.
Explained by clinicaltrials.gg, not part of the registry record. The study team decides who can take part.
Hypersensitivity
An allergy, or another reaction of the immune system, to a substance. “Hypersensitivity to the study drug” means a known allergic reaction to it — not every side effect a medicine can have.
Explained by clinicaltrials.gg, not part of the registry record. The study team decides who can take part.
Participants will be instructed to rinse with 10 mL of their assigned mouthwash twice daily for 1 minute per use, 30 minutes after toothbrushing. The efficacy of the Thymus vulgaris mouthwash in managing biofilm-induced gingivitis will be evaluated by assessing changes in the Plaque Index (PLI), Bleeding on Probing (BOP), Gingival Index (GI), and salivary concentrations of the pro-inflammatory mediators interleukin-1 beta (IL-1β) and matrix metalloproteinase-8 (MMP-8), compared with the placebo and chlorhexidine mouthwash groups.
Biological: 0.2% Thymus vulgaris mouthwash
The participants will be asked to rinse with 10 mL of the assigned mouthwash twice a day for 1 minute for each use, 30 minutes after toothbrushing. The aim of this group is to compare its results with the test group and to show the efficacy of the novel Thymus vulgaris mouthwash.
Biological: Chlorhexidine 0,12%
The participants will be asked to rinse with 10 mL of the assigned mouthwash twice a day for 1 minute for each use, 30 minutes after toothbrushing. The aim of this group is to compare its results with the test group and to show the efficacy of the novel Thymus vulgaris mouthwash.
Biological: Placebo mouthwash
A mouthwash is made using 0.2% Thymus vulgaris essential oil by a medical professional to be used in the management of biofilm-induced gingivitis.
0.12% Chlorhexidine mouthwash (Lacer Perioxidin, Lacer®, Barcelona, Spain) will be used as an active comparator to the test mouthwash.
A placebo mouthwash will be used as a negative control using the same materials used to make the test mouthwash except the Thymus vulgaris essential oil
Bleeding on Probing (BoP)
Bleeding on Probing (BOP) will be assessed by gently inserting a periodontal probe into the gingival sulcus or periodontal pocket, parallel to the long axis of the tooth, using a probing force of approximately 20-25 grams. Bleeding will be assessed 15-30 seconds after probing at each site. Each site will be scored as 0 (no bleeding) or 1 (bleeding present). The possible score for each site ranges from 0 to 1, with higher scores indicating the presence of bleeding and a worse outcome. If expressed as a percentage, BOP will be calculated as the number of sites exhibiting bleeding divided by the total number of sites examined, multiplied by 100; percentages range from 0% to 100%, with higher values indicating more bleeding and a worse outcome.
Time frame: Baseline, 14 days, and 30 days
Plaque Index (PI)
The Modified Quigley-Hein Plaque Index (MQHI) will be used to assess the amount of accumulated dental plaque on all tooth surfaces, excluding the third molars. Six surfaces per tooth will be examined: mesio-buccal, mid-buccal, disto-buccal, mesio-lingual, mid-lingual, and disto-lingual. Dental plaque will be visualized using a disclosing agent (GC Tri Plaque ID Gel, GC Corporation, Japan). Each examined surface will be scored on a scale from 0 to 5 according to the Modified Quigley-Hein Plaque Index criteria, with 0 indicating no plaque and 5 indicating extensive plaque accumulation. The participant's plaque score will be calculated as the mean score of all examined surfaces. Possible mean scores range from 0 to 5, with higher scores indicating greater plaque accumulation and a worse outcome.
Time frame: Baseline, 14 days, and 30 days
Gingival Index (GI)
Gingival Index (GI) will be used to assess the severity of gingival inflammation on the mesial, distal, buccal, and lingual surfaces of all teeth, excluding the third molars. The gingiva will be examined under adequate illumination, and a UNC-15 periodontal probe will be used gently to assess gingival tissue consistency and bleeding tendency where indicated by the index criteria. Each surface will be assigned a score from 0 to 3: 0 indicates normal gingiva with no inflammation; 1 indicates mild inflammation with slight changes in color and texture but no bleeding on probing; 2 indicates moderate inflammation with redness, edema, and bleeding on probing; and 3 indicates severe inflammation with marked redness and edema, ulceration, and a tendency toward spontaneous bleeding. The participant's GI score will be calculated as the mean score of all examined surfaces. Possible mean scores range from 0 to 3, with higher scores indicating more severe gingival inflammation and a worse outcome.
Time frame: Basline, 14 days, and 30 days.
Salivary Interleukin-1 Beta (IL-1β) Concentration
Salivary interleukin-1 beta (IL-1β) concentration will be quantified using an enzyme-linked immunosorbent assay (ELISA), according to the manufacturer's instructions for sample preparation, assay procedures, and result calculation. Results will be expressed in picograms per milliliter (pg/mL).
Time frame: Baseline, 14 days, and 30 days.
Salivary Matrix Metalloproteinase-8 (MMP-8) Concentration
Salivary matrix metalloproteinase-8 (MMP-8) concentration will be quantified using an enzyme-linked immunosorbent assay (ELISA), according to the manufacturer's instructions for sample preparation, assay procedures, and result calculation. Results will be expressed in picograms per milliliter (pg/mL).
Time frame: Baseline, 14 days, and 30 days.
PDFs hosted by the registry, ClinicalTrials.gov.
Plan to share: Yes — De-identified individual participant data underlying the results reported in the published article will be made available, including clinical measurements (Plaque Index, Bleeding on Probing, and Gingival Index), salivary biomarker measurements (interleukin-1 beta and matrix metalloproteinase-8), treatment group assignments, and assessment time points. The dataset will exclude direct personal identifiers.
Supporting information: Study protocol, Statistical analysis plan
Time frame: De-identified individual participant data and selected supporting documents will be available beginning 6 months after publication of the main study results and continuing for 3 years thereafter.
Access criteria: Researchers with scientifically sound research proposals will be eligible to request access to the de-identified individual participant data and selected supporting documents, including the study protocol and statistical analysis plan. Requests will be reviewed by the study investigators, subject to institutional and ethical requirements. Approved data will be shared through a secure method agreed upon with the requesting researcher. Direct personal identifiers will not be shared.
Start is estimated for Dec 2026; primary completion for Apr 2027, 4 months later.
Of 16 phase 2 interventional studies under Gingivitis, half reached primary completion within 2 months of starting (the median), counting those still running; a quarter within 1 and three quarters within 15. This study's planned 4 months is above that.
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 not yet recruiting, as verified in Oct 2026. You cannot join it, but the record below documents what was studied.
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