**2. Methods**

Search strategy: A literature search on Medline MeSH, Cochrane Library, Ovid, Sciencedirect and Embase databases between January 1970 to November 2003 was conducted, with the key words dental caries, toothpaste, fluoride, caries prevention or control, dentifrices, caries control, cariostatic agents, dental caries susceptibility.

The inclusion criteria were randomized controlled clinical trials, quasi-experimental and cohort studies in all languages, where all participants were less than fourteen years old and the main variable evaluated was dental caries reduction using the DMF or dmf index, comparing fluoride toothpaste concentrations between 440-550 ppm and toothpaste with 1000 ppm or more regardless of the initial dental caries level, treatment and nationality (see Table 1).


Only groups related with the meta-analysis objectives were included.

Table 1. Description of studies

Missing or unreported data were directly requested to the authors by e-mail. In the Reed (27) trial, the standard deviation was not reported, standard error was used to recalculate it assuming equal variances following the mean difference formula by Student´s t-test.

Winter et al. (37) did not report the standard error or standard deviation; although one of the authors was contacted, the information could not be compiled. This standard deviation

studied sources, the lowest fluoride intake was from beverages at 4.3%, followed by meals at 26%. The highest fluoride intake came from toothpastes which comprised 69% of the total

The use of 500 ppm fluoride pastes raised the question of how effective this toothpaste is compared with the 1000 or more ppm F toothpastes, in the prevention of dental caries.

Therefore, the aim of this study was to carry out a quantitative systematic review assessing the efficacy of toothpastes with low fluoride concentrations between 440 and 550 ppm in the reduction of dental caries in children under 14 years old compared to toothpastes that

Search strategy: A literature search on Medline MeSH, Cochrane Library, Ovid, Sciencedirect and Embase databases between January 1970 to November 2003 was conducted, with the key words dental caries, toothpaste, fluoride, caries prevention or

The inclusion criteria were randomized controlled clinical trials, quasi-experimental and cohort studies in all languages, where all participants were less than fourteen years old and the main variable evaluated was dental caries reduction using the DMF or dmf index, comparing fluoride toothpaste concentrations between 440-550 ppm and toothpaste with 1000 ppm or more regardless of the initial dental caries level, treatment and nationality (see

Author Year Systemic Fluoride Type Participants Intervention\*

1525 children between 5 and 14

2177 children between 2 and 5

5028 children between 1 and 6

657 children between 9 and 12 500 ppm 1000 ppm

1055 ppm 550 ppm

440 ppm 1450 ppm

500 ppm 1450 ppm

years

years

years

years

RCT double blind

RCT double blind

RCT double blind

assuming equal variances following the mean difference formula by Student´s t-test.

Missing or unreported data were directly requested to the authors by e-mail. In the Reed (27) trial, the standard deviation was not reported, standard error was used to recalculate it

Winter et al. (37) did not report the standard error or standard deviation; although one of the authors was contacted, the information could not be compiled. This standard deviation

control, dentifrices, caries control, cariostatic agents, dental caries susceptibility.

ingested fluoride (15).

contain 1000 or more ppm F.

1973(27) Non fluoridated

2003(6) Non fluoridated

Table 1. Description of studies

comunity

Low (0.08 to 0.5 ppm ) fluoridated community

Non fluoridated

community

community RCT blind

Only groups related with the meta-analysis objectives were included.

**2. Methods** 

Table 1).

Reed

Winter 1989(37)

Davies 2002(10)

Biesbrock

was calculated using the standard error which was obtained from confidence interval reported.

Ammari et al. (1) did not include both the Winter et al. (37) and Reed(27) trials. They argued high drop out percentages (29% and 28% respectively) and lack of explanation for these drop-outs. However, they included a drop-out percentage in their sample size estimation.

For the characteristic description of the studies found initially, the reviewers used an information extraction format, based on the format developed by Sally Hollis y Tina Leonard, Piel Cochrane Group(18).

The Chalmers criteria were used to evaluate the quality of these studies accepting those that had a score of 70% from 100 possible points (24).

The methodological procedure used to evaluate the studies consisted of an individual review by each examiner to verify the quality criteria of each study that complied with the inclusion criteria and graded them in a scorecard design for each of the different content indicators of the instrument. Afterwards, the research group evaluated as a team and assigned individual points to each study, trying to reach a consensus around those in which noticeable differences existed (assigned extreme values). A design format was used to total the final scores of each study. Studies that scored at least 70% were included in the final meta analysis. One trial could not be included in the meta-analysis (see Table2).


Table 2. Excluded studies

This study was free of any conflict of interest, given that no company or pharmaceutical laboratory sponsored its execution, and its final result was not related to any commercial brand that distributes toothpastes in Colombia.

According to the Antioquia Health Secretary's resolution 008430 of 1993, this project was considered a "non risk investigation". It includes literature review techniques and no intervention or intended biological, physiological, psychological or social variable modifications were done on individuals.
