An interventional study of No Caffeine Intake and Low Caffeine Intake in Periodontitis, sponsored by Haoran Feng. Not yet recruiting at 1 site in China. Open to participants aged 18 Years to 55 Years. Per ClinicalTrials.gov, last updated 2026-08-18.
Sponsored by Haoran Feng · Not applicable, Interventional, and Treatment
This study will explore whether caffeine intake can affect recovery after periodontal (gum) treatment.
Periodontitis is a common gum disease caused by bacteria. Even after treatment, some people may still have ongoing inflammation or changes in oral bacteria. Researchers want to know if daily caffeine intake, such as from coffee, may help improve this condition.
In this study, about 90 adults with periodontitis will receive standard periodontal treatment. Participants will be randomly assigned to one of three groups: no caffeine intake, low caffeine intake, or moderate caffeine intake. They will follow these instructions for about 6 months.
Researchers will collect saliva samples and check gum health at several time points after treatment. Saliva will be used to measure inflammation markers and to study changes in oral bacteria. Researchers will also record clinical gum conditions, such as gum pocket depth and bleeding.
The goal of this study is to understand whether caffeine intake can help reduce inflammation, improve oral bacteria balance, and support recovery after periodontal treatment. The results may help provide simple dietary advice to improve long-term gum health.
This study is a randomized controlled trial designed to evaluate the effects of dietary caffeine intake on periodontal treatment outcomes and potential biological mechanisms.
Periodontitis is a chronic inflammatory disease associated with microbial imbalance and increased inflammatory activity. Although standard periodontal treatment can control disease progression, some individuals may continue to experience persistent inflammation during the maintenance phase.
Approximately 90 adults with periodontitis will be recruited and will receive standard non-surgical periodontal treatment. Participants will be randomly assigned to one of three groups according to caffeine intake: no intake, low intake, and moderate intake.
Participants will be followed for 6 months. Saliva samples will be collected at baseline and multiple follow-up time points. These samples will be used to assess inflammatory biomarkers and oral microbiome characteristics. Clinical periodontal parameters will also be recorded during follow-up.
This study aims to evaluate whether dietary caffeine intake influences inflammatory responses, oral microbiome characteristics, and clinical periodontal outcomes after periodontal treatment. The findings may provide evidence for incorporating dietary factors into periodontal disease management.
1,231 studies on the registry are indexed under Periodontitis; 295 are open to participants now.
This study's planned enrollment of 90 is above the median of 44 across 846 interventional studies indexed under Periodontitis.
Browse Periodontitis studies →This is the only study on the registry with Haoran Feng as lead sponsor.
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Exclusion Criteria:
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.
Before you join, the study team explains what taking part involves — its purpose, what happens, the risks and possible benefits — and answers your questions, so you can decide freely. Consent is usually recorded on a form (the informed consent form, ICF) signed by you or, where the law allows, by someone legally authorised to decide for you.
You can keep asking questions during the study, you are told of new information that matters, and you can choose to leave at any time.
A weakened immune system. It can come from an illness, such as HIV or some blood cancers, or from medicines that turn the immune system down, for example after an organ transplant or for an autoimmune disease; steroids at higher doses count.
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Informed consent
Before you join, the study team explains what taking part involves — its purpose, what happens, the risks and possible benefits — and answers your questions, so you can decide freely. Consent is usually recorded on a form (the informed consent form, ICF) signed by you or, where the law allows, by someone legally authorised to decide for you.
You can keep asking questions during the study, you are told of new information that matters, and you can choose to leave at any time.
Explained by clinicaltrials.gg, not part of the registry record. The study team decides who can take part.
Immunosuppression
A weakened immune system. It can come from an illness, such as HIV or some blood cancers, or from medicines that turn the immune system down, for example after an organ transplant or for an autoimmune disease; steroids at higher doses count.
Read whether the line is about a condition or about medicines, and which medicines and doses it means.
Explained by clinicaltrials.gg, not part of the registry record. The study team decides who can take part.
Participants will receive standard non-surgical periodontal treatment and will be instructed to avoid dietary caffeine intake throughout the 6-month study period.
Dietary Supplement: No Caffeine Intake
Participants will receive standard non-surgical periodontal treatment and will consume approximately 50 mg of dietary caffeine per day throughout the 6-month study period.
Dietary Supplement: Low Caffeine Intake
Participants will receive standard non-surgical periodontal treatment and will consume approximately 100 mg of dietary caffeine per day throughout the 6-month study period.
Dietary Supplement: Moderate Caffeine Intake
Participants will receive standard non-surgical periodontal treatment and will be instructed to avoid all dietary sources of caffeine throughout the 6-month study period.
Participants will receive standard non-surgical periodontal treatment and will consume approximately 50 mg of dietary caffeine per day throughout the 6-month study period.
Participants will receive standard non-surgical periodontal treatment and will consume approximately 100 mg of dietary caffeine per day throughout the 6-month study period.
Mean Change From Baseline in Salivary Matrix Metalloproteinase-8 Concentration at 2 Weeks, 1 Month, 3 Months, and 6 Months
Unstimulated whole saliva will be collected at baseline and at 2 weeks, 1 month, 3 months, and 6 months after initiation of the intervention. Salivary matrix metalloproteinase-8 concentration will be quantified using a commercial enzyme-linked immunosorbent assay kit. For each participant, change from baseline will be calculated separately at each post-baseline time point. The outcome will be summarized as the mean change from baseline for each intervention arm at each time point.
Time frame: Baseline, 2 weeks, 1 month, 3 months, and 6 months after initiation of the intervention
Mean Change From Baseline in Salivary Interleukin-1 Beta Concentration at 2 Weeks, 1 Month, 3 Months, and 6 Months
Unstimulated whole saliva will be collected at baseline and at 2 weeks, 1 month, 3 months, and 6 months after initiation of the intervention. Salivary interleukin-1 beta concentration will be quantified using a commercial enzyme-linked immunosorbent assay kit. For each participant, change from baseline will be calculated separately at each post-baseline time point. The outcome will be summarized as the mean change from baseline for each intervention arm at each time point.
Time frame: Baseline, 2 weeks, 1 month, 3 months, and 6 months after initiation of the intervention
Mean Change From Baseline in Salivary Interleukin-6 Concentration at 2 Weeks, 1 Month, 3 Months, and 6 Months
Unstimulated whole saliva will be collected at baseline and at 2 weeks, 1 month, 3 months, and 6 months after initiation of the intervention. Salivary interleukin-6 concentration will be quantified using a commercial enzyme-linked immunosorbent assay kit. For each participant, change from baseline will be calculated separately at each post-baseline time point. The outcome will be summarized as the mean change from baseline for each intervention arm at each time point.
Time frame: Baseline, 2 weeks, 1 month, 3 months, and 6 months after initiation of the intervention
Mean Change From Baseline in the Shannon Diversity Index of the Salivary Microbiome at 2 Weeks, 1 Month, 3 Months, and 6 Months
Salivary microbiome composition will be assessed using 16S ribosomal RNA gene sequencing. Alpha diversity will be quantified using the Shannon diversity index at baseline and at 2 weeks, 1 month, 3 months, and 6 months after initiation of the intervention. For each participant, change from baseline will be calculated separately at each post-baseline time point. The outcome will be summarized as the mean change from baseline for each intervention arm at each time point.
Time frame: Baseline, 2 weeks, 1 month, 3 months, and 6 months after initiation of the intervention.
Mean Change From Baseline in the Relative Abundance of Porphyromonas gingivalis in Saliva at 2 Weeks, 1 Month, 3 Months, and 6 Months.
The relative abundance of Porphyromonas gingivalis in saliva will be estimated using 16S ribosomal RNA gene sequencing and reported as a percentage. For each participant, change from baseline will be calculated separately at 2 weeks, 1 month, 3 months, and 6 months after initiation of the intervention. The outcome will be summarized as the mean change in percentage points for each intervention arm at each time point.
Time frame: Baseline, 2 weeks, 1 month, 3 months, and 6 months after initiation of the intervention.
Mean Change From Baseline in Full-Mouth Mean Probing Depth at 2 Weeks, 1 Month, 3 Months, and 6 Months
Probing depth will be measured in millimeters by one trained and calibrated periodontal examiner using a Florida electronic periodontal probe at six sites per tooth. For each participant, full-mouth mean probing depth will be calculated across all examined periodontal sites at each assessment. Change from baseline will be calculated separately at 2 weeks, 1 month, 3 months, and 6 months. The outcome will be summarized as the mean change from baseline for each intervention arm at each time point.
Time frame: Baseline, 2 weeks, 1 month, 3 months, and 6 months after initiation of the intervention.
Mean Change From Baseline in Full-Mouth Mean Clinical Attachment Level at 2 Weeks, 1 Month, 3 Months, and 6 Months
Clinical attachment level will be measured in millimeters by one trained and calibrated periodontal examiner using a Florida electronic periodontal probe at six sites per tooth. For each participant, full-mouth mean clinical attachment level will be calculated across all examined periodontal sites at each assessment. Change from baseline will be calculated separately at 2 weeks, 1 month, 3 months, and 6 months. The outcome will be summarized as the mean change from baseline for each intervention arm at each time point.
Time frame: Baseline, 2 weeks, 1 month, 3 months, and 6 months after initiation of the intervention
Mean Change From Baseline in the Percentage of Periodontal Sites With Bleeding on Probing at 2 Weeks, 1 Month, 3 Months, and 6 Months
Bleeding on probing will be assessed by one trained and calibrated periodontal examiner at six sites per tooth. For each participant, the percentage of periodontal sites with bleeding on probing will be calculated as the number of sites showing bleeding divided by the total number of sites examined, multiplied by 100. Change from baseline will be calculated separately at 2 weeks, 1 month, 3 months, and 6 months. The outcome will be summarized as the mean change in percentage points for each intervention arm at each time point.
Time frame: Baseline, 2 weeks, 1 month, 3 months, and 6 months after initiation of the intervention
Plan to share: Yes — De-identified individual participant data used for the published results will be shared, including demographic information, periodontal clinical parameters, salivary inflammatory biomarker measurements (MMP-8, IL-1β, and IL-6), and oral microbiome sequencing data. The study protocol and statistical analysis plan will also be available upon reasonable request.
Supporting information: Study protocol, Statistical analysis plan, Informed consent form
Time frame: Beginning 6 months after publication and ending 5 years after publication.
Access criteria: De-identified individual participant data and supporting documents will be available to qualified researchers who submit a methodologically sound research proposal. Requests should be directed to the corresponding investigator. Access will be granted after review and approval of the proposal and execution of a data sharing agreement, in accordance with institutional policies and applicable ethical requirements.
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This study is not yet recruiting, as verified in Aug 2026. You cannot join it, but the record below documents what was studied.
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