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Xylitol Adult Caries Trial (X-ACT)

This study has been completed.
National Institute of Dental and Craniofacial Research (NIDCR)
Information provided by (Responsible Party):
Jim Bader, DDS, University of North Carolina, Chapel Hill Identifier:
First received: October 25, 2006
Last updated: September 9, 2011
Last verified: September 2011
The purpose of the trial is to determine the extent to which daily use of xylitol lozenges reduces the appearance of new caries lesions in adults who tend to experience such lesions (i.e., caries-active adults).

Condition Intervention Phase
Dental Caries Dietary Supplement: xylitol Dietary Supplement: inactive lozenge Phase 3

Study Type: Interventional
Study Design: Allocation: Randomized
Intervention Model: Parallel Assignment
Masking: Double Blind (Participant, Care Provider, Investigator, Outcomes Assessor)
Primary Purpose: Prevention
Official Title: Xylitol Adult Caries Trial (X-ACT)

Resource links provided by NLM:

Further study details as provided by Jim Bader, DDS, University of North Carolina, Chapel Hill:

Primary Outcome Measures:
  • combined root and coronal D2FS (dental caries) increment [ Time Frame: 3 year ]

Secondary Outcome Measures:
  • combined root and coronal D12FS (dental caries) increment [ Time Frame: three year ]
  • separate root and coronal D12FS (dental caries) increments [ Time Frame: 3 years ]
  • association of lozenge use with D12FS (dental caries) in control group only [ Time Frame: 3 years ]

Enrollment: 709
Study Start Date: January 2007
Study Completion Date: June 2011
Primary Completion Date: June 2011 (Final data collection date for primary outcome measure)
Arms Assigned Interventions
Experimental: xylitol lozenge
1g xylitol lozenge. Five/day, dissolved in mouth
Dietary Supplement: xylitol
1g xylitol lozenges to be dissolved in mouth. Five lozenges daily for three years
Placebo Comparator: inactive lozenge
1g placebo lozenge. Five/day, dissolved in mouth
Dietary Supplement: inactive lozenge
1g inactive lozenge, dissolved in mouth. Five/day for three years
Other Name: placebo

Detailed Description:

Dental caries incidence is higher in adults than children. Recent recommendations from both the Centers for Disease Control and an NIH Consensus Development Conference on dental caries call for clinical trials of caries prevention methods in caries-active adults. Little is known about the effectiveness of caries prevention methods in adults, and virtually no information exists with respect to prevention among adults who are at elevated risk for developing caries lesions. This application describes a clinical trial of an intervention to prevent dental caries in caries-active adults that is responsive to the CDC and Consensus Conference recommendations.

The Xylitol for Adult Caries Trial (X-ACT) is a three-year, multi-center, randomized, placebo-controlled, double-blind study to determine the effectiveness of xylitol lozenges in reducing the incidence of coronal and root caries in caries-active adults. The intervention is the daily use of xylitol lozenges. Participants will be 750 adults (ages 25-75) with current or recent caries lesions who are dental school patients at one of three Clinical Centers in Chapel Hill, NC, Birmingham, AL, and San Antonio TX. These Clinical Centers offer diverse populations with substantial proportions of minority populations that enhance the generalizability of the findings. The Study Chair is located at the University of North Carolina-Chapel Hill, and the Data Coordinating Center is at the Kaiser Permanente Center for Health Research in Portland, OR.

This intervention is being tested because it represents a potentially effective caries prevention method with a high likelihood of adoption by dental practitioners as an "add on" caries preventive method for their caries-active patients. The potential for adoption of the intervention is an important consideration because current data suggest that caries-active adults are underexposed to caries-preventive treatment in dental practices. If effective, the intervention also holds potential as a public health measure.


Ages Eligible for Study:   25 Years to 80 Years   (Adult, Senior)
Sexes Eligible for Study:   All
Accepts Healthy Volunteers:   No

Inclusion Criteria:

  • age 25-80
  • at least one caries lesion in year prior to enrollment
  • at least 12 teeth without crowns
  • no allergies to xylitol or aspartame
  • anticipate remaining in area for 3 years

Exclusion Criteria:

  • 10 or more caries lesions in year prior to enrollment
  • currently receiving long-term antibiotic therapy
  • history of head and neck radiation
  Contacts and Locations
Choosing to participate in a study is an important personal decision. Talk with your doctor and family members or friends about deciding to join a study. To learn more about this study, you or your doctor may contact the study research staff using the Contacts provided below. For general information, see Learn About Clinical Studies.

Please refer to this study by its identifier: NCT00393055

United States, Alabama
University of Alabama at Birmingham
Birmingham, Alabama, United States, 35294-0111
United States, North Carolina
University of North Carolina School of Dentistry
Chapel Hill,, North Carolina, United States, 27599-7450
United States, Texas
University of Texas Health Science Center
San Antonio, Texas, United States, 78229-3900
Sponsors and Collaborators
University of North Carolina, Chapel Hill
National Institute of Dental and Craniofacial Research (NIDCR)
Principal Investigator: James D Bader, DDS MPH UNC School of Dentistry
  More Information

Publications automatically indexed to this study by Identifier (NCT Number):
Responsible Party: Jim Bader, DDS, Res Prof, University of North Carolina, Chapel Hill Identifier: NCT00393055     History of Changes
Other Study ID Numbers: NIDCR-18038
U01DE018038 ( US NIH Grant/Contract Award Number )
Study First Received: October 25, 2006
Last Updated: September 9, 2011

Additional relevant MeSH terms:
Dental Caries
Tooth Demineralization
Tooth Diseases
Stomatognathic Diseases processed this record on June 23, 2017