Condition category
Oral Health
Date applied
Date assigned
Last edited
Retrospectively registered
Overall trial status
Recruitment status
No longer recruiting

Plain English Summary

Background and study aims
Periodontitis is a chronic inflammatory disease affecting the tissue surrounding the teeth, and if left untreated it may result in bone damage and subsequent tooth loss. The disease is very common worldwide, in Sweden affecting approximately 1/3 of the population. Rheumatoid arthritis (RA) is a lifelong autoimmune disease, where the normally protective immune system attacks the joints, resulting in swelling, stiffness and pain. This incurable disease affects approximately 1% of the world’s population, mostly women. Previous studies have shown that patients with RA may have increased risk of periodontitis in general and that non-surgical periodontal treatment may have beneficial effects on RA disease activity. The aim of this study is to investigate the severity of periodontitis in patients with RA and weather frequent periodontal treatment (every three months) results in improvement of RA disease activity and periodontal parameters in patients with RA and periodontitis.

Who can participate?
Patients with RA and periodontal disease, ≥ 18 .

What does the study involve?
Participants receive a dental examination at the beginning of the study. Those with periodontitis will be randomly divided to one of two groups. Those in the first groupeceive a more frequent periodontal treatment every three months, and those in the second group receive periodontal treatment only at the first visit. The periodontal treatment includes oral hygiene instructions and removal of plaque and tartar by a dental professional. Patients with severe periodontitis in need of specialist treatment are referred to and treated by a dentist who specializes in periodontal disease/a periodontist.

What are the possible benefits and risks of participating?
The main benefits of participating in the study include surveillance and treatment of the periodontal disease performed frequently (every three months) by a dentist. Also the patients in the control group benefit from conventional periodontal treatment at the inclusion into the study. The side effects of periodontal treatment include sore gums and gum recession due to reduced inflammation. This is a low risk study since all the participants receive conventional periodontal treatment during the first visit as well as surveillance of the periodontitis throughout the course of the study.

Where is the study run from?
Karolinska University Hospital (Sweden)

When is study starting and how long is it expected to run for?
December 2015 to December 2018.

Who is funding the study?
Partly funded by the Stockholm County Council, the collaborative European Union's FP7 Research Project TRIGGER, Karolinska Institutet, the Swedish Research Council, the Swedish Dental Society and others.

Who is the main contact?
1. Associate Professor Tülay Yucel-Lindberg
2. PhD, DDS, Kaja Eriksson

Trial website

Contact information



Primary contact

Dr Tülay Yucel-Lindberg


Contact details

Department of Dental Medicine
Division of periodontology
Karolinska Institutet
141 04

Additional identifiers

EudraCT number number

Protocol/serial number


Study information

Scientific title

The severity of periodontitis and the effects of periodontal treatment on disease activity of patients with rheumatoid arthritis as well as the influence of medication on periodontitis: A randomized controlled trial


Periodontitis in RA (PEIRA)

Study hypothesis

The hypotheses of this study are:
1. Severe form of periodontitis is more common in seropositive (ACPA/RF) patients with RA as compared to seronegative.
2. Frequent periodontal treatment reduces rheumatoid arthritis disease activity, and related autoimmune and inflammatory parameters.
3. The microbial profile differs based on rheumatological and/or periodontal characteristics in patients with RA.

Ethics approval

1. Regional Ethical Review Board Stockholmm, 10/06/2009, ref: Dnr 2009/792-31/4
2. Regional Ethical Review Board Stockholmm, 30/04/2015, ref: 2015/766-32

Study design

Prospective randomized interventional clinical controlled trial

Primary study design


Secondary study design

Trial setting


Trial type


Patient information sheet

Not available in web format, please use the contact details below to request a patient information sheet


Periodontitis and Rheumatoid Arthritis


After a full-mouth dental and periodontal examination, participants with periodontitis are randomized to one of two groups.

Those in the first group receive conventional periodontal treatment only at the time of inclusion into the study (control group).

Those in the second group undergo the periodontal treatment every three months (intervention group) for one year year. The conventional periodontal treatment includes oral hygiene instructions, supra- and subgingival scaling and root planning. Patients in need of specialist treatment (e.g. surgical periodontal treatment) are remitted to periodontal clinic.

Participants are assessed for their rheumatoid arthritis activity at baseline and at the study end. Participants are also evaluated for their periodontal parameters such as probing pocket depth, clinical attachment loss, antibodies, microbial profiles and inflammatory mediators.

Intervention type



Drug names

Primary outcome measure

1. Rheumatoid arthritis (RA) disease activity is measured using the DAS28 score, HAQ score at baseline and one year
2. Periodontal parameters (such as probing pocket depth, clinical attachment loss) are measured using the methods of measurement of periodontal disease/parameters at baseline and months three, six, nine, and twelve

Secondary outcome measures

1. The microbial profile is assessed using sequencing technology throughout the study (the specific time points depend on the availability of the resources as well as the instruments at core facility)
2. Antibody levels (such as ACPA/RF, periodontal pathogens etc) are measured using multiplex immunoassay, nephelometry and/or ELISA technique at baseline and one year
3. Levels of inflammatory mediators are measured using Luminex immunoassay at baseline and one year

Overall trial start date


Overall trial end date


Reason abandoned (if study stopped)


Participant inclusion criteria

1. ≥ 18 years of age
2. Fulfilling the 2010 ACR criteria for RA
3. Moderate to severe periodontitis, defined according to the classification criteria of the CDC Working Group meant for usage in Population-Based Surveillance of Periodontitis
4. Written informed consent to participate
5. Swedish national registration number

Participant type


Age group




Target number of participants


Participant exclusion criteria

1. Antibiotic treatment ≤3 months prior to inclusion into the study
2. Periodontal treatment (surgical or non-surgical) ≤3 months prior to inclusion into the study
3. Pregnancy
4. Simultaneous participation in other interventional studies

Recruitment start date


Recruitment end date



Countries of recruitment


Trial participating centre

Rheumatology Clinics at Karolinska University Hospital (Huddinge and Solna)
141 86 Stockholm (Huddinge) 171 76 Stockholm (Solna)
141 86

Sponsor information


Karolinska Institutet

Sponsor details

Karolinska Institutet
Deptartment of Dental Medicine
SE-141 04

Sponsor type




Funder type

Not defined

Funder name

Stockholms Läns Landsting

Alternative name(s)

Funding Body Type

Funding Body Subtype


Funder name


Alternative name(s)

Swedish Research Council, VR

Funding Body Type

government organisation

Funding Body Subtype

National government



Funder name

Swedish Dental Society

Alternative name(s)

Funding Body Type

Funding Body Subtype


Funder name

Swedish Rheumatic Foundation

Alternative name(s)

Funding Body Type

Funding Body Subtype


Funder name

Karolinska Institutet

Alternative name(s)

Karolinska Institute, KI

Funding Body Type

government organisation

Funding Body Subtype

Local government



Results and Publications

Publication and dissemination plan

Planned publication in a high-impact peer reviewed journal with intent to publish 2019/2020

IPD sharing statement:
The data sharing plans for the current study are unknown and will be made available at a later date

Intention to publish date


Participant level data

To be made available at a later date

Basic results (scientific)

Publication list

Publication citations

Additional files

Editorial Notes

09/12/2019: The following changes were made to the trial record: 1. The overall end date was changed from 31/12/2018 to 31/12/2021. 2. The intention to publish date was changed from 01/01/2020 to 01/01/2021.