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Protocol Details

Bacterial Arrangement in Supragingival Biofilms

This study is NOT currently recruiting participants.

Summary | Eligibility | Citations | Contacts




Sponsoring Institute

National Institute of Dental And Craniofacial Research (NIDCR)

Recruitment Detail

Type: Completed Study; data analyses ongoing
Gender: Male & Female
Min Age: 18
Max Age: 999

Referral Letter Required


Population Exclusion(s)



Dental Plaque;
Bacterial Interactions;
Receptor Polysaccharide;
Oral Streptococci;
Natural History

Recruitment Keyword(s)



Dental Plaque;
Oral Health;
Periodontal Disease and Caries;
Periodontal Disease

Investigational Drug(s)


Investigational Device(s)




Supporting Site

National Institute of Dental and Craniofacial Research


- Dental plaque is a coating of bacteria on the teeth. It contributes to poor dental health and diseases such as gingivitis, cavities and periodontal disease. Researchers who study plaque know that many different types of oral bacteria stick to each other in test-tube experiments. However, it is not clear if these interactions occur in natural dental plaque. By studying how bacteria interact, researchers can better understand how bacteria come together and grow to form plaque.


- To look at how bacteria interact with one another to form dental plaque.


- Healthy nonsmoking volunteers at least 18 years of age.


- Participants will be screened with a medical history and dental exam. They will also have dental impressions taken for a stent (a device similar to Invisalign(SqrRoot) braces).

- Participants will wear the stent for up to 8 hours a day on selected study visit days. It will contain enamel chips made from sterilized human teeth. The mouth bacteria will stick to the chips and grow. Chips will be taken out of the stent twice during these study visit days.

- Participants will have other study visits to provide saliva and plaque samples. They will also have gum swabs to collect bacteria.

- Some participants may have a second set of study visits. At these visits, they will chew gum to increase their saliva production. Afterwards, they will wear the stent with the enamel chips for 4 hours. Samples from the stent will be taken once on these study visit days.

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-Healthy adult subjects (as determined from self-reported medical history, evaluation by study dentist and nursing assessment, per policy).

-18 years of age or older

-Good oral health as determined by screening oral examination with:

--no history of oral cancer

-- no active periodontal disease.


-History of any medical conditions affecting salivary flow, such as Sj(SqrRoot)(Delta)gren s syndrome

-History of any immunosuppressant therapy, such as glucocorticoids (within the last year), auto-immune or immune diseases such as ulcerative colitis or systemic lupus erythematosis, or current steroid therapy, other than topical, within the last 30 days

-History of cardiac, kidney, liver and lung disorders

-Use of tobacco within the last year

-Use of antibiotics within the preceding four months

-Use of medications thought to affect salivary flow such as head/neck radiation therapy, diuretics, or nitrates. Medications will be checked against product information for effect and reviewed by the protocol dentist.

-Clinically visible active dental caries.

-Active periodontal disease as defined as no more than 4 sites in the entire mouth with greater than or equal to 5mm probing depths.

-History of severe allergic reactions (Anaphylaxis) to several allergins and specific allergies to or other substances found in the stent or impression material (ie: Plasticized Methacrylate Polymer, methyl methacrylate monomer, alkyl dimethacrylate, benzophenone, Toluidine and Hydroquinone), waxes containing Pine Rosin, and to the list of ingredients for the impression material.

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Palmer RJ Jr, Shah N, Valm A, Paster B, Dewhirst F, Inui T, Cisar JO. Interbacterial Adhesion Networks within Early Oral Biofilms of Single Human Hosts. Appl Environ Microbiol. 2017 May 17;83(11). pii: e00407-17. doi: 10.1128/AEM.00407-17. Print 2017 Jun 1.

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Principal Investigator

Referral Contact

For more information:

Niki M. Moutsopoulos, D.D.S.
National Institute of Dental And Craniofacial Research (NIDCR)
NIHBC 30 BG RM 327
(301) 435-7182

Laurie D. Brenchley
National Institute of Dental And Craniofacial Research (NIDCR)
National Institutes of Health
Building 10
Room 1N117
10 Center Drive
Bethesda, Maryland 20892
(301) 451-2551

Office of Patient Recruitment
National Institutes of Health Clinical Center (CC)
Building 61, 10 Cloister Court
Bethesda, Maryland 20892
Toll Free: 1-800-411-1222
Local Phone: 301-451-4383
TTY: TTY Users Dial 7-1-1

Clinical Trials Number:


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