Caffeine Intake and Periodontal Treatment Outcomes

Official title

Effects of Dietary Caffeine Intake on Periodontal Treatment Outcomes: A Randomized Controlled Trial

Overview

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.

Detailed description

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.

Interventions

• Dietary supplement No 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.
• Dietary supplement Low 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 Moderate 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.

Primary outcome measures

• Mean Change From Baseline in Salivary Matrix Metalloproteinase-8 Concentration at 2 Weeks, 1 Month, 3 Months, and 6 Months [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 [Time frame: Baseline, 2 weeks, 1 month, 3 months, and 6 months after initiation of the intervention]

Secondary outcome measures (6)

• Mean Change From Baseline in Salivary Interleukin-6 Concentration at 2 Weeks, 1 Month, 3 Months, and 6 Months [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 [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. [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 [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 [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 [Time frame: Baseline, 2 weeks, 1 month, 3 months, and 6 months after initiation of the intervention]

Eligibility criteria

Inclusion criteria

• Adults aged 18 to 55 years.
• Diagnosed with periodontitis according to the 2018 Classification of Periodontal and Peri-Implant Diseases and Conditions.
• First visit for periodontal treatment and eligible for standard non-surgical periodontal therapy.
• Willing and able to comply with the dietary intervention and scheduled follow-up visits.
• Able to understand the study procedures and provide written informed consent.
• Able to communicate effectively and complete study questionnaires and follow-up assessments.

Exclusion criteria

• Pregnant or breastfeeding women, or women planning pregnancy during the study period.
• History of periodontal treatment within the previous 6 months.
• Current smokers or tobacco users.
• Use of antibiotics, anti-inflammatory drugs, immunosuppressive agents, or medications known to affect periodontal status within the previous 3 months.
• Presence of systemic diseases that may influence periodontal conditions, including diabetes mellitus, hypertension, or hyperlipidemia.
• Severe systemic diseases, psychiatric disorders, or other conditions that may interfere with study participation or protocol compliance.
• Allergy or intolerance to caffeine or inability to comply with the dietary caffeine intervention.
• Individuals with limited hand function or other conditions preventing adequate oral hygiene practices.

Criteria are shown verbatim from the registry (in English). Final eligibility is always assessed by the study center.

Healthy volunteers: No

Study design

Allocation

Randomized

Model

Parallel assignment

Masking

Open label

Primary purpose

Treatment

Study locations

China · 1 center

• Affiliated Stomatological Hospital of Xuzhou Medical University — Xuzhou

Identifiers

NCT: NCT07747545 · 2026-KY-008-02

Primary sources (government registries)

• ClinicalTrials.gov (US NIH)

View this study on ClinicalTrials.gov ↗