Condition category
Nutritional, Metabolic, Endocrine
Date applied
Date assigned
Last edited
Retrospectively registered
Overall trial status
Recruitment status
No longer recruiting
Publication status

Plain English Summary

Background and study aims
Type 2 diabetes and gum disease (periodontitis) are common diseases and often found in the same patients. There is strong evidence to suggest that diabetes predisposes patients to gum disease and vice versa. The mechanism linking both diseases could be increased body inflammation affecting both sugar control and gum health. Ongoing gum disease could make it harder for people with diabetes to control their sugar levels. The aim of this study is therefore to assess whether treating gum disease improves sugar levels (metabolic control) in patients with type 2 diabetes.

Who can participate?
Patients aged 18 and over with type 2 diabetes and moderate to severe gum disease

What does the study involve?
Participants undergo an oral examination, blood sample and some blood vessels scans at their first visit and at 2, 6 and 12 months after the start of their gum/dental treatment. After the first study visit, participants are randomly allocated into two groups: one group receive an intensive course of gum/dental therapy and the other group receive scaling and polishing. All participants are monitored every 3 months up to 1 year from the start of the gum treatment.

What are the possible benefits and risks of participating?
Participants benefit from an update on their oral and gum health. They receive treatment from a professional dedicated team of specialists/dentists/hygienists to look after their gum condition within and beyond the duration of the study. The study does not involve any drug treatment but involves frequent blood samples and blood vessel scanning (ultrasound scans) (every 2-3 months).

Where is the study run from?
UCL Eastman Dental Institute (UK)

When is the study starting and how long is it expected to run for?
July 2007 to January 2015

Who is funding the study?
1. Diabetes UK
2. NIHR Biomedical Research Centre UCL/ULCH (UK)

Who is the main contact?
1. Prof. Francesco D’Aiuto
2. Dr Jean Suvan

Trial website

Contact information



Primary contact

Prof Francesco D'Aiuto


Contact details

Study Principal Investigator
UCL Eastman Dental Institute
256 Gray's Inn Road
United Kingdom



Additional contact

Dr Jean Suvan


Contact details

UCL Eastman Dental Institute
Periodontology Unit
256 Grays Inn Road
United Kingdom

Additional identifiers

EudraCT number number

Protocol/serial number


Study information

Scientific title

Treatment of periodontitis and metabolic control in patients with type 2 diabetes mellitus: a single-centre randomised interventional trial



Study hypothesis

Current hypothesis as of 26/09/2017:
Untreated periodontitis impacts on patients’ oral health and overall quality of life. Periodontitis could worsen metabolic control, vascular function in patients with type 2 diabetes via an increased systemic inflammatory burden. The trialists therefore hypothesized that effective treatment of periodontitis, which results in reduction of local and systemic inflammation, would improve glycaemic control, as well as vascular and renal function and quality of life in patients with type 2 diabetes.

Previous hypothesis:
This study aims at assessing the potential benefit of successful periodontitis treatment on glucose control in people with type 2 diabetes. The secondary aims include changes in vascular function, wound healing and inflammation and quality of life.

Ethics approval

The Joint UCL/UCLH Committees on the Ethics of Human Research, 27/11/2007, ref: 07/H0714/97

Study design

Parallel-arm single (examiner) blinded randomized controlled single-centre trial

Primary study design


Secondary study design

Randomised controlled trial

Trial setting


Trial type


Patient information sheet

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


Topic: Diabetes Research Network, Oral and Gastrointestinal; Subtopic: Type 2, Oral and Gastrointestinal (all Subtopics); Disease: Cardiovascular disease, Diabetic Control, Other, Oral & Dental


Participants will be randomly assigned to either usual periodontal care (supragingival scaling and polishing) or to an intensive periodontal treatment (test group). Blood samples will be collected at almost every visit to assess glucose control between study groups. Samples will also be collected to assess the changes in wound healing and blood vessel health before and after gum therapy in both groups. A subgroup of 30 participants will also undergo more detailed analysis of gingival wound healing processes after periodontal therapy. Study follow-up is at 12 months.

Study entry: single randomisation only

Contact details for Patient Information Material:
Eastman Clinical Investigation Centre
256 Gray's Inn Road
London, WC1X 8LD
United Kingdom
Tel: +44 (0)20 7915 2334
Fax: +44 (0)20 7915 1213

Intervention type



Phase III

Drug names

Primary outcome measure

Change in HbA1c between test and control group after 12 months of completion of therapy

Secondary outcome measures

Current secondary outcome measures as of 26/09/2017:
1. HbA1c difference at 6 months
2. Glucose, insulin, creatinine and flow-mediated dilatation at 6 and 12 months
3. Adverse events at any study visits
4. Periodontal clinical parameters, lipid fractions, inflammatory and endothelial cell surface markers at 2, 6 and 12 months
5. eGFR and patient reported outcomes at 12 months
6. Changes in dental plaque composition at 2, 6 and 12 months visits
7. Laser Doppler flowmetry of the skin at all study visits, a subgroup of 30 patients will also have laser Doppler measures of their gums following intensive gum therapy
8. Intima-media thickness and endothelium pulse amplitude tonometry changes at 12 months (subgroup of 115 patients)

Previous secondary outcome measures:
1. To assess the impact of extensive periodontal therapy on:
1.1. Markers of gingival wound healing
1.2. Assessment of endothelial function
1.3. Subclinical atherosclerosis
1.4. Systemic inflammation
1.5. Proteinuria
1.6. Microbiological differences
In individuals with type 2 diabetes compared to control
2. To assess changes in quality of life, both related to diabetes and oral health, after extensive periodontal therapy compared to control

Overall trial start date


Overall trial end date


Reason abandoned (if study stopped)


Participant inclusion criteria

1. Subject aged over 18 years, either sex
2. Subject diagnosed with type 2 diabetes mellitus
3. Subject consenting to the study
4. Subject with signs of active moderate to severe periodontitis (at least 20 periodontal pockets, probing pocket depth [PPD] greater than 4 mm and bleeding on probing)
5. Minimum of 15 teeth present

Participant type


Age group




Target number of participants

Planned sample size: 280; UK sample size: 280

Participant exclusion criteria

1. Pregnancy/lactation
2. Subjects on chronic treatment with phenytoin or cyclosporin
3. Subjects with known human immunodeficiency virus (HIV) or hepatitis (B, C) or uncontrolled systemic diseases (cardiovascular diseases including hypertension, liver, pulmonary diseases, end stage renal failure) and/or neoplasm
4. Subjects who require antibiotic coverage for periodontal procedures

Recruitment start date


Recruitment end date



Countries of recruitment

United Kingdom

Trial participating centre

UCL Eastman Dental Institute
United Kingdom

Sponsor information


UCL Eastman Dental Institute and Hospital, University College London (UK)

Sponsor details

256 Gray's Inn Road
United Kingdom

Sponsor type

Hospital/treatment centre



Funder type


Funder name

Diabetes UK (UK) (ref: 08/0003594 and 08/0003741)

Alternative name(s)

Funding Body Type

private sector organisation

Funding Body Subtype

other non-profit


United Kingdom

Funder name

NIHR Biomedical Research Centre UCL/ULCH

Alternative name(s)

Funding Body Type

Funding Body Subtype


Results and Publications

Publication and dissemination plan

1. A main manuscript with the primary and secondary results will be published in a peer-review journal (under review)
2. UCL Team will be presenting the main results at dental and medical scientific meetings
3. UCL Media Relations would make every effort to publicise any appropriate information relevant to the study results to the international press
4. Electronic copies of any research papers arising from this work will be made freely available at the UCL repository of journal articles
5. Dissemination of the relevant findings to the general public, press, companies will be pursued using the UCL Public Engagement in Science website

IPD sharing statement
The datasets generated and/or analysed during the current study during this study will be included in the subsequent results publication

Intention to publish date


Participant level data


Basic results (scientific)

Publication list

2018 results in:

Publication citations

Additional files

Editorial Notes

18/02/2019: IPD sharing statement added. 27/11/2018: Publication reference added. 26/09/2017: The following changes were made to the trial record: 1. Plain English summary added. 2. The study design was changed from 'Single-centre randomised interventional prevention and treatment trial' to 'Parallel-arm single (examiner) blinded randomized controlled single-centre trial'. 3. NIHR Biomedical Research Centre UCL/ULCH was added as a funder. 4. Publication and dissemination plan and IPD sharing statement added. 5. The overall trial start date was changed from 01/11/2008 to 01/07/2007. 6. The overall trial end date was changed from 31/12/2011 to 01/01/2015. 7. The recruitment start date was changed from 01/11/2008 to 01/10/2007. 8. The recruitment end date was changed from 31/12/2011 to 31/10/2012.