Condition category
Nervous System Diseases
Date applied
Date assigned
Last edited
Retrospectively registered
Overall trial status
Recruitment status
No longer recruiting

Plain English Summary

Background and study aims
An important cause of inflammation (soreness and swelling), especially in older people, is gum disease. This can be treated by improving oral health – dentists can fix damaged teeth and dental hygienists can help to keep the gums healthy by cleaning and by providing advice. Some evidence suggests that inflammation is also important in Alzheimer's disease. This inflammation, both that caused by gum disease and that associated with Alzheimer's, can be measured in the blood. This study aims to find out if people with mild memory problems have inflammation that can be measured in their blood and whether improving gum health reduces that inflammation. If it does, then the next step, in another study, would be to see whether this affects the risk of getting Alzheimer's disease.

Who can participate?
People over the age of 65 who do not have dementia but do have some memory problems can participate in the study.

What does the study involve?
People taking part in the study will be randomly allocated to two groups: one receives an intensive dental treatment and the other, usual care. They will have an assessment of their memory and a blood and saliva test. Then they will see a dentist and a dental hygienist. Some will have regular treatment – fixing any major problems with their teeth and advice about how to keep the gums healthy. Others will have more intensive dental hygiene.

What are the possible benefits and risks of participating?
The possible benefits are a good assessment of tooth and gum health for all participants followed by either normal standard of care or more intensive oral health treatment. The risks are nothing more than that of having a blood test.

Where is the study run from?
This is a study at King's Health Partners – a group of hospitals including the Maudsley, King's College and Guys and St Thomas', London, UK.

When is the study starting and how long is it expected to run for?
The study started in November 2011 and will run through to November 2014.

Who is funding the study?
The Biomedical Research Centres at King's Health Partners, UK.

Who is the main contact?
Professor Simon Lovestone

Trial website

Contact information



Primary contact

Dr Mark Ide


Contact details

Dental Institute
King's College London
Periodontology Floor 21 Tower Wing
Guy’s Hospital
Great Maze Pond
London Bridge
United Kingdom
+44 (0)20 7188 5391

Additional identifiers

EudraCT number number

Protocol/serial number


Study information

Scientific title

Control of periodontal inflammation, systemic inflammatory responses and cognitive decline: a comparative study of standard oral care versus periodontal care


Study hypothesis

1. To investigate relationships between periodontal disease (and associated systemic inflammatory responses) and both progression of cognitive decline and gene expression in T cells and dendritic cells in response to such inflammatory changes.
2. To determine the feasibility of a hub and spoke-based community assessment of oral and mental health, and secondary care provision of dental treatment, for the improvement of oral health and changes in systemic markers of inflammation as a precursor to a larger intervention study to determine how this influences cognitive decline, mediated by and related to changes in lymphocyte activity.

Ethics approval

NRES Committee London - East- Chair Dr Joyce Smith, 5th September 2011, reference number: 11/LO/0987

Study design

Interventional randomised single centre study

Primary study design


Secondary study design

Randomised controlled trial

Trial setting


Trial type

Quality of life

Patient information sheet

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


Periodontitis and disease progression in Alzheimer’s disease


Recruited individuals are stratified for gender and randomised into either a periodontal care or a standard care group using a random number table.

Provision of oral hygiene instruction using a Braun Oral B electric toothbrush provided for the patient and supplemented by use of chlorhexidine mouthwash for one month.

Full mouth tooth and root instrumentation under local anaesthesia over 4 visits, with tailored oral hygiene reinforcement at each visit, and where necessary, removal of hopeless teeth and removal of decay and provisional restorations in decayed teeth/ repair of decayed fillings

Intervention type



Not Applicable

Drug names

Primary outcome measures

If periodontal treatment is feasible and effective in improving oral health in people with mild cognitive impairment (primary outcome A: changes in plaque scores, probing depths and bleeding scores), measured at 6-7 weeks

Secondary outcome measures

1. If periodontal treatment is effective in changing levels of circulating proinflammatory cytokines (change in CRP and IL-6)
2. If periodontal treatment reduces rate of cognitive decline (change in CERAD score in 6 weeks; secondary outcome B change in rate of conversion to dementia over 1 year)
3. Whether there is a shared complex inflammatory marker for periodontitis and mild cognitive impairment and whether change in this marker set predicts response to therapy (shared marker set, predictive value of marker set)

Measured at 6 months and final assessment at one year.

Overall trial start date


Overall trial end date


Reason abandoned


Participant inclusion criteria

1. Adults aged 70 years or older, either sex
2. Amnestic according to Consortium to Establish a Registry for Alzheimer's Disease (CERAD) cognitive battery norms
3. Mini–Mental State Examination (MMSE) score range between 24−30
4. Geriatric Depression Scale less than/equals 4/5
5. Clinical Dementia rating scale score of less than/equals 0.5
6. Participants should be nonsmoking, in good general health and English speaking in order to allow valid cognitive assessment to take place
7. Willing and able to participate in study

Participant type


Age group



Not Specified

Target number of participants


Participant exclusion criteria

1. Less than 70 years old
2. Recent change in relevant medication
3. Current or recent smoker.
4. With 8 teeth or less
5. Not deemed sufficiently fit to undergo operative dental treatment including extractions
6. Recent active periodontal treatment
7. Reporting a history of local oropharyngeal radiotherapy resulting in oral dryness

Recruitment start date


Recruitment end date



Countries of recruitment

United Kingdom

Trial participating centre

Dental Institute
United Kingdom

Sponsor information


King's College London (UK)

Sponsor details

c/o Keith Brennan
Hodgkin Building
St Thomas Street
United Kingdom
+44 (0)20 7848 6960

Sponsor type




Funder type

Hospital/treatment centre

Funder name

NIHR Biomedical Research Centres at South London and Maudsley NHS Foundation Trust (SLaM) and Guy's and St Thomas' NHS Foundation Trust (GST) with King's College London (KCL) (UK)

Alternative name(s)

Funding Body Type

Funding Body Subtype


Results and Publications

Publication and dissemination plan

Not provided at time of registration

Intention to publish date

Participant level data

Not provided at time of registration

Results - basic reporting

Publication summary

Publication citations

Additional files

Editorial Notes