Dental Caries
Conditions
Keywords
Calcium glycerophosphate, Fluoride, Dentifrice, Biofilm, Dental caries
Brief summary
The aim of this study was to investigate the buffering effect of a calcium glycerophosphate-fluoride (CaGP-F) dentifrice on in vivo dental biofilm after a cariogenic challenge and evaluate its probable 12-hour protective effect. Twelve young adults took part in this randomized, double blind, 14-day 4-phase crossover study. Between each phase, the volunteers had a 1-week wash-out period. Coded dentifrices were randomly assigned to the volunteers: A) no F and no CaGP; B) CaGP-only (0.13%); C) F-only (1500 ppm (ppm= parts per million of fluoride which is equivalent to mg/kg)); D) CaGP-F (0.13%, 1500 ppm, respectively). The pH measurements were taken from a single-site using a microelectrode, with salt bridge established by a 1M KCl (one molar potassium chloride) solution with a reference electrode. pH measurements were taken at 0 (baseline), 1, 7, 14 and 21 min (minutes) after a cariogenic challenge (10% w/v sucrose solution, %w/v = percent weight per volume). Four sets of measurements were carried out: (D0BS) before test dentifrice usage; (D01min) 1-min after test dentifrice usage; and (D712h) 7 days and (D1412h) 14 days using the test dentifrice, 12 hours (h)after brushing. Stephen curves and mean AUC (area under the curve) were obtained.
Detailed description
Although the mechanisms of action of fluoride are reasonably understood, the mechanism of calcium phosphate and calcium glycerophosphate (CaGP) are still a matter of debate. It has been suggested that CaGP increases the phosphorus content in the biofilm and, as a result, the buffering capacity of the biofilm is intensified. The pH levels of the biofilm are maintained above the 5.0-5.5 range. This is above the critical range for enamel demineralization.
Interventions
DRUGcalcium glycerophosphate
use of a dentifrice containing CaGP (0.13%) and no fluoride
DRUGno active ingredient
dentifrice without calcium glycerophosphate and no fluoride
DRUGfluoride
use of a dentifrice containing fluoride (1500ppm) only
DRUGCAGP + fluoride
calcium glycerophosphate and fluoride dentifrice
Sponsors
Conselho Nacional de Desenvolvimento Científico e Tecnológico
Coordination for the Improvement of Higher Education Personnel
Federal University of Paraíba
Study design
Allocation
RANDOMIZED
Intervention model
CROSSOVER
Primary purpose
PREVENTION
Masking
TRIPLE (Subject, Caregiver, Investigator)
Eligibility
Sex/Gender
ALL
Age
19 Years to 30 Years
Healthy volunteers
Yes
Inclusion criteria
* to live in a non-fluoridated area * to have at least 20 natural teeth * signed a consent form agreeing to carefully follow the research instructions
Exclusion criteria
* presence of active caries lesions * periodontal disease * use of antibiotics/medication.
Design outcomes
Primary
| Measure | Time frame | Description |
|---|---|---|
| Minimum pH | at 1 minute (minimum fermenting pH) or at 7 minutes | The dental biofilm pH was measured in vivo with the microtouch method, using a palladium microelectrode + reference electrode. Data represents the mean values of the lowest pH observed each time after the use of sucrose. |
| Minimum pH After 14 Days of Use of Dentifrice | 14 days | measurement of pH obtained as described before. However, this time the biofilm was exposed to the dentifrices for a longer period (14 days). |
Countries
Brazil
Participant flow
Recruitment details
The subjects were dental students of the University. The recruitment locations were dental clinics of the faculty and laboratory facilities. The dates of recruitment included 2-3 months before starting the research in January 2006; and lasted for 2 months afterwards
Pre-assignment details
As a pre-assignment procedure, all volunteers signed an informed consent. The the volunteers received a dental hygiene kit containing a toothbrush and a fluoride-free and calcium-free dentifrice as part of the 1-week wash-out period prior to group assignment.
Participants by arm
| Arm | Count |
|---|---|
| Toothbrushing The study was based on the use of dentifrices for daily oral hygiene in a crossover design. The volunteers were asked to use the placebo and test dentifrices for one week. During the study, the volunteers were instructed to brush their teeth normally until 3 days before the measurements. During these 3 days, they were instructed to brush only the occlusal surfaces of their teeth until 12 hours before the pH measurements, when they should stop brushing altogether for dental plaque pH evaluation. | 12 |
| Total | 12 |
Baseline characteristics
| Characteristic | Toothbrushing |
|---|---|
| Age, Categorical <=18 years | 0 Participants |
| Age, Categorical >=65 years | 0 Participants |
| Age, Categorical Between 18 and 65 years | 12 Participants |
| Age Continuous | 26 years STANDARD_DEVIATION 3 |
| Region of Enrollment Brazil | 12 participants |
| Sex: Female, Male Female | 6 Participants |
| Sex: Female, Male Male | 6 Participants |
Adverse events
| Event type | EG000 affected / at risk |
|---|---|
| deaths Total, all-cause mortality | — / — |
| other Total, other adverse events | 0 / 0 |
| serious Total, serious adverse events | 0 / 0 |
Outcome results
Primary
Minimum pH
The dental biofilm pH was measured in vivo with the microtouch method, using a palladium microelectrode + reference electrode. Data represents the mean values of the lowest pH observed each time after the use of sucrose.
Time frame: at 1 minute (minimum fermenting pH) or at 7 minutes
Population: The number of subjects were determined by a pilot study carried out in 3 volunteers. The study has a crossover design. Thus the 4 groups of dentifrices tested included the same subjects in a different time-measurement avoiding the influence of individual variables in the analysis.
| Arm | Measure | Value (MEAN) | Dispersion |
|---|---|---|---|
| Control | Minimum pH | 5.40 pH | Standard Deviation 0.6 |
| Calcium Glycerophosphate | Minimum pH | 5.48 pH | Standard Deviation 0.65 |
| Fluoride | Minimum pH | 5.25 pH | Standard Deviation 0.77 |
| Calcium Glycerophosphate and Fluoride | Minimum pH | 5.70 pH | Standard Deviation 0.43 |
Comparison: The study was based on the use of dentifrices for daily oral hygiene in a crossover design. The null hyphothesis was no difference between pH values of the groups. The statistical analysis was by repeated measurements ANOVA.p-value: 0.001ANOVA
Comparison: The comparison was based on mean and median values of plaque pH in different moments of cariogenic challenge. The null hypothesis was that no diference between the groups wil be found. The test hypothesis was that the experimental dentifrice of CaGP-F would provide a better control of plaque pH after 14 days of use.p-value: 0.001ANOVA
Primary
Minimum pH After 14 Days of Use of Dentifrice
measurement of pH obtained as described before. However, this time the biofilm was exposed to the dentifrices for a longer period (14 days).
Time frame: 14 days
Population: The initial part of the work as a pilot study.
| Arm | Measure | Value (MEAN) | Dispersion |
|---|---|---|---|
| Control | Minimum pH After 14 Days of Use of Dentifrice | 4.78 pH | Standard Deviation 0.67 |
| Calcium Glycerophosphate | Minimum pH After 14 Days of Use of Dentifrice | 5.24 pH | Standard Deviation 0.83 |
| Fluoride | Minimum pH After 14 Days of Use of Dentifrice | 5.25 pH | Standard Deviation 0.71 |
| Calcium Glycerophosphate and Fluoride | Minimum pH After 14 Days of Use of Dentifrice | 5.44 pH | Standard Deviation 0.59 |
Comparison: The groups were compared by repeated measurements anova. There was no power calculation, but a pilot study to check the minimal number necessary of subjects in order to find a signifcant difference between interventions.p-value: 0.01ANOVA