Periodontitis in Patients With Osteoarthritis

November 7, 2026 updated by: Ivana Bradvica, University of Zagreb

Presence of Periodontitis in Patients With Osteoarthritis

The aim of the study is to determine the prevalence of periodontitis in patients with osteoarthritis. Methods: A case-control study is planned. The research would include patients of the Orthopaedic Clinic, University Hospital Centre Zagreb that have been diagnosed with osteoarthritis (cases). The control group would be patients from the Dental Polyclinic Zagreb, where the research will be conducted. All patients would undergo a dental examination to determine their periodontal status and periodontitis stage. Demographic parameters would include: age, gender, education, alcohol and cigarette consumption, exercise habits, BMI, oral hygiene habits, medication and medical history. Expected results: The aim of the study is to determine if there is a link between periodontitis and osteoarthritis. In patients with osteoarthritis a higher prevalence of periodontitis is expected, as well as more advanced stages of periodontitis, compared to the subjects of the control group. Scientific contribution: The results of the study might further confirm and strengthen the association between periodontitis and osteoarthritis. For the first time the proposed study will explore the presence of five key periodontopathogens in periodontal tissues and synovial fluid patients with periodontitis and osteoarthritis and examine the quality of life related to oral health.

Study Overview

Status

Status

Indicates the current recruitment status or the expanded access status.
Recruiting

Conditions

Conditions

The disease, disorder, syndrome, illness, or injury that is being studied. On ClinicalTrials.gov, conditions may also include other health-related issues, such as lifespan, quality of life, and health risks.

Intervention / Treatment

Intervention / Treatment

A process or action that is the focus of a clinical study. Interventions include drugs, medical devices, procedures, vaccines, and other products that are either investigational or already available. Interventions can also include noninvasive approaches, such as education or modifying diet and exercise.

Study Type

Study Type

Describes the nature of a clinical study. Study types include interventional studies (also called clinical trials), observational studies (including patient registries), and expanded access.
Observational

Enrollment (Estimated)

Enrollment

The number of participants in a clinical study. The "anticipated" enrollment is the target number of participants that the researchers need for the study.
60

Contacts and Locations

This section provides the contact details for those conducting the study, and information on where this study is being conducted.

Study Contact

Study Contact

The name and contact information for the person who can answer enrollment questions for a clinical study. Each location where the study is being conducted may also have a specific contact, who may be better able to answer those questions.

Study Contact Backup

  • Name: Ivan Puhar
  • Phone Number: +38598566276
  • Email: puhar@sfzg.hr

Study Locations

  • Croatia
    • City of Zagreb
      • Zagreb, City of Zagreb, Croatia, 10000
      • Zagreb, City of Zagreb, Croatia, 10000
        • Recruiting
        • Stomatološka poliklinika Zagreb
        • Contact:
        • Contact:

Participation Criteria

Researchers look for people who fit a certain description, called eligibility criteria. Some examples of these criteria are a person's general health condition or prior treatments.

Eligibility Criteria

Eligibility Criteria

The key requirements that people who want to participate in a clinical study must meet or the characteristics they must have. Eligibility criteria consist of both inclusion criteria (which are required for a person to participate in the study) and exclusion criteria (which prevent a person from participating). Types of eligibility criteria include whether a study accepts healthy volunteers, has age or age group requirements, or is limited by sex.

Ages Eligible for Study

18 years and older (Adult, Older Adult)

Accepts Healthy Volunteers

Yes

Genders Eligible for Study

All

Sampling Method

Probability Sample

Study Population

The research would include patients from the Orthopedic Clinic of the University Hospital Centre Zagreb who have been diagnosed with knee or hip osteoarthritis (study group), and patients from the Dental Polyclinic Zagreb (control group), where the research will also be conducted. Patients would be divided into two subgroups depending on whether they have periodontitis or not.

Description

Inclusion Criteria:

Diagnosed primary osteoarthritis of grade 4 according to the Kellgren-Lawrence scale Patients who are independently mobile or mobile with the aid of a walker or forearm crutches Signed informed consent Minimum of twenty teeth in the jaw (third molars are excluded)

Exclusion Criteria:

Use of systemic antibiotics or periodontal therapy performed within the last six months Systemic diseases known to be risk factors for the development of periodontitis (diabetes mellitus, obesity, rheumatoid arthritis, depression, hematological diseases) Secondary osteoarthritis Parkinson's disease Pregnant or breastfeeding women Neoplasms

Study Plan

This section provides details of the study plan, including how the study is designed and what the study is measuring.

How is the study designed?

Design Details

  • Observational Models: OTHER
  • Time Perspectives: CROSS_SECTIONAL

Cohorts and Interventions

Group / Cohort

Group / Cohort

A group or subgroup of participants in an observational study that is assessed for biomedical or health outcomes.
Intervention / Treatment

Intervention / Treatment

A process or action that is the focus of a clinical study. Interventions include drugs, medical devices, procedures, vaccines, and other products that are either investigational or already available. Interventions can also include noninvasive approaches, such as education or modifying diet and exercise.
patients with osteoarthritis
Other: No Interventions

This is an observational study, and participants did not receive any study-specific intervention measures.
patients without osteoarthritis
Other: No Interventions

This is an observational study, and participants did not receive any study-specific intervention measures.

What is the study measuring?

Primary Outcome Measures

Primary Outcome Measures

In a clinical study's protocol, the planned outcome measure that is the most important for evaluating the effect of an intervention/treatment. Most clinical studies have one primary outcome measure, but some have more than one.
Outcome Measure
Measure Description
Time Frame
PPD
Time Frame: Baseline (single assessment)

Periodontal probing depth - the distance in millimeters from the gingival margin to the base of the periodontal pocket. It is measured using a standard periodontal probe at 6 sites per tooth. Higher values indicate deeper periodontal pockets (worse periodontal status), while lower values indicate shallower pockets (better periodontal status).
Baseline (single assessment)
PCR microbiological testing
Time Frame: Baseline (single assessment)

PCR test (polymerase chain reaction, 7500 Real-Time PCR System, Applied Biosystems/Method RT-PCR with Sybr-Green/melting curve analysis, validated according to micro-IDent®, Hain Lifescience GmbH, CE-IVD and PeriodontScreen Real-TM CE, Sacace Biotechnologies) is planned for the most common periodontopathogenic bacteria: Aggregatibacter actinomycetemcomitans, Porphyromonas gingivalis, Tannerella forsythensis, Prevotella intermedia, and Treponema denticola. The test would be taken from all patients in the study group diagnosed with periodontitis.

Samples of bacteria would be collected from the periodontal pocket and synovial fluid. When testing bacteria from periodontal pockets, sterile paper points are inserted to the bottom of the deepest pockets and left in situ for 20 seconds. The paper points are then placed in a sterile test tube, tightly closed, and sent to the molecular laboratory of the Analiza Polyclinic. The procedure for collecting bacteria from synovial fluid also include
Baseline (single assessment)

Secondary Outcome Measures

Secondary Outcome Measures

In a clinical study's protocol, a planned outcome measure that is not as important as the primary outcome measure for evaluating the effect of an intervention but is still of interest. Most clinical studies have more than one secondary outcome measure.
Outcome Measure
Measure Description
Time Frame
OHIP-14
Time Frame: Baseline (single assessment)

OHIP-14 is a 14-item questionnaire that assesses the impact of oral health on oral health-related quality of life. Each item is scored on a Likert scale from 0 to 4 (0 = never, 1 = hardly ever, 2 = occasionally, 3 = fairly often, 4 = very often). The total score ranges from 0 to 56. Higher scores indicate worse oral health-related quality of life, while lower scores indicate better oral health-related quality of life.
Baseline (single assessment)
RE
Time Frame: Baseline (single assessment)

Gingival recession is the distance in millimeters from the cementoenamel junction to the gingival margin. It is measured using a standard periodontal probe. Higher values indicate more pronounced gingival recession (worse condition), while lower values or a value of 0 indicate a normal position of the gingival margin.
Baseline (single assessment)
CAL
Time Frame: Baseline (single assessment)

Clinical attachment level is the sum of probing depth and gingival recession at a given tooth site, expressed in millimeters. It represents the distance from the cementoenamel junction to the base of the periodontal pocket. Higher values indicate greater clinical attachment loss (worse condition), while lower values indicate a more preserved periodontal supporting structures.
Baseline (single assessment)
FMPS
Time Frame: Baseline (single assessment)

Full-mouth plaque score - plaque accumulation will be assessing the presence or absence of supragingival plaque on six surfaces of each tooth. The results will be expressed as the percentage of plaque-positive surfaces relative to the total number of examined surfaces. FMPS is calculated by dividing the number of sites with plaque by the total number of examined sites and multiplying by 100. Scores range from 0% to 100%. Higher percentages indicate greater plaque accumulation (worse condition), while lower percentages indicate better oral hygiene.
Baseline (single assessment)
FMBS
Time Frame: Baseline (single assessment)

Full-mouth bleeding score - gingival inflammation will be assessed recorded dichotomously (presence/absence of bleeding) following gentle probing of the gingival sulcus at standardized sites. The outcome will be expressed as the percentage of bleeding-positive sites, reflecting the degree of gingival inflammatory response. FMBS is calculated by dividing the number of bleeding sites by the total number of examined sites and multiplying by 100. Scores range from 0% to 100%. Higher percentages indicate greater gingival inflammation (worse condition), while lower percentages indicate healthier gingival tissue.
Baseline (single assessment)

Collaborators and Investigators

This is where you will find people and organizations involved with this study.

Sponsor

Sponsor

The organization or person who initiates the study and who has authority and control over the study.
University of Zagreb

Study record dates

These dates track the progress of study record and summary results submissions to ClinicalTrials.gov. Study records and reported results are reviewed by the National Library of Medicine (NLM) to make sure they meet specific quality control standards before being posted on the public website.

Study Major Dates

Study Start (Actual)

Study Start

The actual date on which the first participant was enrolled in a clinical study. The "anticipated" study start date is the date that the researchers think will be the study start date.
January 15, 2025

Primary Completion (Estimated)

Primary Completion

The date on which the last participant in a clinical study was examined or received an intervention to collect final data for the primary outcome measure. Whether the clinical study ended according to the protocol or was terminated does not affect this date. For clinical studies with more than one primary outcome measure with different completion dates, this term refers to the date on which data collection is completed for all the primary outcome measures. The "anticipated" primary completion date is the date that the researchers think will be the primary completion date for the study.
June 1, 2027

Study Completion (Estimated)

Study Completion

The date on which the last participant in a clinical study was examined or received an intervention/treatment to collect final data for the primary outcome measures, secondary outcome measures, and adverse events (that is, the last participant's last visit). The "anticipated" study completion date is the date that the researchers think will be the study completion date.
July 1, 2027

Study Registration Dates

First Submitted

First Submitted

The date on which the study sponsor or investigator first submitted a study record to ClinicalTrials.gov. There is typically a delay of a few days between the first submitted date and the record's availability on ClinicalTrials.gov (the first posted date).
November 7, 2026

First Submitted That Met QC Criteria

First Submitted That Met QC Criteria

The date on which the study sponsor or investigator first submits a study record that is consistent with National Library of Medicine (NLM) quality control (QC) review criteria. The sponsor or investigator may need to revise and submit a study record one or more times before NLM's QC review criteria are met. It is the responsibility of the sponsor or investigator to ensure that the study record is consistent with the NLM QC review criteria.
November 7, 2026

First Posted (Actual)

First Posted

The date on which the study record was first available on ClinicalTrials.gov after National Library of Medicine (NLM) quality control (QC) review has concluded. There is typically a delay of a few days between the date the study sponsor or investigator submitted the study record and the first posted date.
November 13, 2026

Study Record Updates

Last Update Posted (Actual)

Last Update Posted

The most recent date on which changes to a study record were made available on ClinicalTrials.gov. There may be a delay between when the changes were submitted to ClinicalTrials.gov by the study's sponsor or investigator (the last update submitted date) and the last update posted date.
November 13, 2026

Last Update Submitted That Met QC Criteria

Last Update Submitted That Met QC Criteria

The most recent date on which the study sponsor or investigator submitted changes to a study record that are consistent with National Library of Medicine (NLM) quality control (QC) review criteria. It is the responsibility of the sponsor or investigator to ensure that the study record is consistent with the NLM QC review criteria.
November 7, 2026

Last Verified

Last Verified

The most recent date on which the study sponsor or investigator confirmed the information about a clinical study on ClinicalTrials.gov as accurate and current. If a study with a recruitment status of recruiting; not yet recruiting; or active, not recruiting has not been confirmed within the past 2 years, the study's recruitment status is shown as unknown.
November 1, 2026

More Information

Terms related to this study

Additional Relevant MeSH Terms

Other Study ID Numbers

Other Study ID Numbers

Identifiers or ID numbers other than the NCT number that are assigned to a clinical study by the study's sponsor, funders, or others. These numbers may include unique identifiers from other trial registries and National Institutes of Health grant numbers.
  • 05-PA-12-3/2024

Plan for Individual participant data (IPD)

Plan to Share Individual Participant Data (IPD)?

NO

Drug and device information, study documents

Studies a U.S. FDA-regulated drug product

No

Studies a U.S. FDA-regulated device product

No

This information was retrieved directly from the website clinicaltrials.gov without any changes. If you have any requests to change, remove or update your study details, please contact register@clinicaltrials.gov. As soon as a change is implemented on clinicaltrials.gov, this will be updated automatically on our website as well.

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