Effects of flossing and rinsing with a fluoridated mouthwash after brushing with a fluoridated toothpaste on salivary fluoride clearance.

The aims of this study were to test the hypothesis that flossing after brushing with a fluoridated toothpaste may lower salivary fluoride (F), and to evaluate the consequence of subsequent F mouthwash use. Twenty adults used 3 oral hygiene regimes in a randomised order: A, brushing with an NaF toothpaste; B, as A but followed by professional flossing; C, as B followed by rinsing with an NaF mouthwash. Saliva samples were collected up to 120 min after each regime and analysed for F. The mean area under the clearance curve value for regime C was statistically significantly greater than the corresponding values for A and B (p < 0.0001), which differed little. The regime that included the mouthwash may provide better anticaries protection.

Statistical issues for combining multiple caries diagnostics for demonstrating caries efficacy.

Caries efficacy in clinical trials has been based primarily on visual examinations supplemented by Fiber Optic Transillumination (FOTI) and radiography, with the assessments combined at the surface level to classify each surface as to its caries status. Newer caries diagnostics techniques measure the caries process in a quantitative manner and so thus yield continuous rather than ordinal results. The objective of this study was to examine various methods for the analysis of multiple outcomes in clinical trials and to compare their usefulness for the analysis of caries trials. Four global tests (rank sum, ordinary least squares, general least squares, and generalized estimating equations) and two caries indices (based on average and maximum values of the methods) were evaluated with the use of one-year follow-up data from 1063 children in a recent caries trial. A new hybrid method was also developed and evaluated. All of the methods performed well when the diagnostic measures showed product differences in caries in the same direction. Ease of use, interpretability, and distributional assumptions must be considered before a consensus method for analysis of multiple diagnostic measures in caries trials can be determined.

A three-year clinical trial of a combination of trimetaphosphate and sodium fluoride in silica toothpastes.

The relative efficacy of NaF silica toothpastes containing 1000 ppm fluoride and 1500 ppm fluoride in the control of dental caries is not clear-cut. Also, it has not been established that incorporation of trimetaphosphate (TMP) improves the anticaries activity of NaF toothpastes. A three-year clinical trial was conducted to test the hypotheses that: (i) the anticaries activity of NaF toothpastes containing 1500 ppm F was greater than that of NaF toothpastes containing 1000 ppm F, and (ii) inclusion of TMP improved the efficacy of NaF silica pastes. Subsidiary aims included determination of whether frequency of toothbrushing and method of rinsing after brushing were correlated with caries increments. The study involved 4196 children aged 11 to 12 years at outset. These participants had been selected from a pool of 7374 potential subjects on the basis of caries experience and dental eruption pattern. They were stratified by sex, examiner, and presence of calculus and caries, and were allocated at random to one of the four toothpastes under study. Using mirror and probe and also FOTI, we carried out clinical examinations at baseline and annually thereafter for 3 yrs. Bitewing radiographs of a subset of children were taken at baseline and at the end of the study. The outcome measure for the study, DMFS increment, was defined as the increase in caries over 3 yrs, taking into account changes occurring on individual tooth surfaces. Data for 3467 subjects were available for analyses at both baseline and year 3 examinations. Radiographs were taken for 1942 subjects at both baseline and year 3 examinations. The mean three-year clinical-only DMFS increment for the subjects using 1500-ppm-NaF pastes was 3.93, which was 6% lower than the corresponding mean of 4.19 for the 1000-ppm-NaF pastes. There was no significant difference between the mean DMFS increment for those using paste with or without TMP. Subjects who claimed to brush more frequently or who claimed not to use a tumbler to rinse after toothbrushing had lower three-year DFMS increments.

An abbreviated caries clinical trial design validated over 24 months.

Conventional caries trials last from 24 to 36 months. This study evaluated whether the previously established difference in efficacy between 1000- and 2500-ppm-fluoride dentifrices could be detected after 12 months. Caries was assessed by clinical visual assessment (CVA-simplified version of Dundee Selectable Threshold Method - DSTM), bitewing radiography, and Fiber Optic Transillumination (FOTI). Changes in status for individual surfaces were classified by means of pre-prepared matrices as 0 (unchanged), +1 (initiation or progression), or -1 (regression) and summed for each subject to yield an event score. Mean group event scores were calculated for each product. DSTM at the D(1) [enamel and dentin] threshold showed significant inter-group differences in mean event scores (p < 0.003) and D(1)MFS increment (< 0.007) at 12 months; these were confirmed at 24 months by traditional increment analysis (CVA & FOTI at the D(3) (dentin only) threshold + radiography, p < 0.03). This study confirms the validity of an abbreviated trial protocol.

Effect of low levels of fluoride on calcium uptake by demineralized human enamel.

The effect of fluoride (ca. 0.1 parts/10(6)) on calcium uptake by enamel was examined under alternating remineralizing and demineralizing conditions. The remineralizing solutions contained either 0, 0.058, 0.104, or 0.138 parts/10(6) fluoride (ex NaF), while the demineralizing solutions contained no added fluoride. During the demineralization periods, calcium loss was similar for all groups. However, during the remineralizing periods, all levels of added fluoride were found to promote calcium uptake. Calcium levels taken up by the artificial lesions were sound to increase with increasing fluoride concentration in solution, and were independent of surface area of exposed enamel. In the absence of fluoride, even under conditions that are considered to be remineralizing, further demineralization took place.

Increasing the sensitivity of caries clinical trials by applying logistic modelling to specific teeth.

An alternative statistical approach is proposed for analysing data from longitudinal clinical trials. Caries increments on those teeth which are known to be particularly susceptible to caries for the population under study are represented by a linear logistic probability model. Expression of the caries increments in the form of a probability model should lead to a better understanding of the relative importance of the various factors which contribute to the caries increment in the population under study. When this model was applied to caries increments on the permanent second molars of children aged 11-13 yr at the baseline of two 3-yr trials, the sensitivity of statistical analysis was up to five times greater than that obtained with traditional statistical methods.

Improved sensitivity in caries clinical trials by selection on the basis of baseline caries experience.

As caries prevalence in some countries declines, and panel sizes for discriminating anti-caries clinical trials inevitably increase, the need for participant pre-selection grows to avoid escalating cost and manpower problems. Hence, retrospective analyses of data were undertaken, from a 3-yr double-blind caries clinical trial where a linear fluoride dose-response had been obtained. As a result, it was demonstrated that the eruption status of permanent second molars, in 3005 participants aged 11-12 yr at outset, when coupled with their baseline clinical DMFT values, provided a sound basis for panellist size prediction without loss of sensitivity. Thus, had only those subjects with DMFT greater than 4, with at least three of their permanent second molars erupted been selected following clinical baseline examination, the same sensitivity would have been achieved with 52% fewer subjects. Furthermore, using these criteria, selection can be made on site, in real time, and a child informed whether its immediate participation in a trial is possible.

A 3-year oral health dose-response study of sodium monofluorophosphate dentifrices with and without zinc citrate: anti-caries results.

A 3-yr clinical trial has been conducted on 3000 12-yr-old children in Lanarkshire, Scotland, with the aim of investigating the effects on oral health of toothpastes containing both sodium monofluorophosphate and zinc citrate, the former being present at fluoride levels of 1000, 1500, and 2500 ppm F. No significant difference in caries increments was found between the group of children using toothpastes incorporating zinc citrate and their counterparts using zinc-free pastes. However, a significant anti-caries dose-response was demonstrated over the SMFP range used. This dose-response was evident for boys and girls and also for the various types of teeth and tooth surfaces.

The effect of dentifrices containing Triclosan on the development of gingivitis in a 21-day experimental gingivitis study.

The aim of this study was to investigate the ability of Triclosan dentifrices to delay the development of gingivitis during a 21-day period without toothbrushing. Test pastes contained 0.3 per cent Triclosan; seven also contained 0.75 per cent zinc citrate; one other contained 2 per cent Gantrez. Plaque and gingivitis increased significantly (p < 0.001) between day 0 and day 21 in the control group. there was no evidence to reject the assumption of similar efficacy across the seven Triclosan/zinc citrate variants. For the combined Triclosan/zinc citrate groups, statistically significant reductions in plaque formation and in gingivitis relative to the control were recorded. Reductions in plaque and gingival bleeding compared to control for the Triclosan/Gantrez group were not statistically significant, although reductions in gingival indices were. The greater reduction in the Gingival Index of the Triclosan/zinc citrate group was also statistically significantly different from that of the Triclosan/Gantrez group, suggesting that a dentifrice containing the former would have a greater antigingivitis potential than a dentifrice containing the latter.

The effects of a silica dentifrice containing Triclosan and zinc citrate on supragingival plaque and calculus formation and the control of gingivitis.

A double blind, 7-month parallel clinical study was conducted to determine the effect of a dentifrice containing 0.3 per cent Triclosan and 0.75 per cent zinc citrate in a 0.8 per cent sodium monofluorophosphate/silica base on supragingival plaque, gingivitis and supragingival calculus formation, compared to a 0.8 per cent monofluorophosphate/silica control dentifrice. The results of this clinical study demonstrate that the use of the Triclosan/zinc citrate dentifrice over a 7-month period provided a statistically significant and clinically relevant benefit in controlling gingivitis, compared to a control dentifrice. Supragingival plaque and calculus levels were also significantly reduced in comparison to the effects of a control dentifrice.

The effects of three silica dentifrices containing Triclosan on supragingival plaque and calculus formation and on gingivitis.

A double blind, seven month clinical study was conducted to determine the effects of three Triclosan containing test dentifrices on supragingival plaque, gingivitis and supragingival calculus formation compared to a 0.8 per cent monofluorophosphate-silica control dentifrice. Each test dentifrice contained 0.3 per cent Triclosan; additionally one contained 0.75 per cent zinc citrate, the second contained 2 per cent Gantrez and the third contained 5 per cent pyrophosphate. Subjects were assigned to one of the three test groups or to the control group according to random allocation within nine strata. Subjects were evaluated for supragingival plaque and calculus formation and for gingivitis after one, four and seven months' use of the dentifrices. After seven months, the Triclosan/Gantrez and the Triclosan/pyrophosphate dentifrices each provided a statistically significant reduction of approximately 25 per cent in gingival bleeding compared to the control. Neither dentifrice gave statistically significant reductions in supragingival plaque or calculus formation. In contrast, the Triclosan/zinc citrate dentifrice provided statistically significant reductions of 33 per cent in supragingival plaque, 51 per cent in gingival bleeding and 67 per cent in supragingival calculus formation. The reductions in gingival bleeding and calculus formation were statistically superior to those of the Triclosan/Gantrez and the Triclosan/pyrophosphate products. The results demonstrate that use of the Triclosan/zinc citrate dentifrice over a seven month period provided statistically significant and clinically relevant reductions in supragingival plaque and calculus formation, and control of gingivitis as compared to a control dentifrice.

An intervention programme to establish regular toothbrushing: understanding parents' beliefs and motivating children.

AIMS/OBJECTIVES: To determine the benefit of twice daily toothbrushing on newly erupted first permanent molars. To investigate, through the Health Belief Model, how parents' beliefs influence the likelihood of their children brushing twice a day. To identify aspects of a toothbrushing intervention programme that can be used in general dental practice. DESIGN: Randomised controlled trial. SETTING: Schools in deprived communities in Scotland. PARTICIPANTS: 461, 5-year-old children. INTERVENTIONS/METHODS: Supervised toothbrushing on school-days with a 1,000 ppm chalk-based fluoride toothpaste for two years. A school and home-based incentive scheme including toothbrushing charts, 6-monthly dental examinations and parental questionnaires. MAIN OUTCOME MEASURES: Caries increment and twice daily toothbrushing. RESULTS: In the control group, children who brushed once a day or less had 64% more caries than those who brushed at least twice a day (P = 0.001). In the intervention group this difference in caries was reduced to 16% (P > 0.05). The most significant parental belief explaining variation in twice-daily brushing was whether parents feel strongly that there is time to check their child's toothbrushing (P = 0.0001). The odds of these parents reporting that their child brushes twice daily are nearly three times greater. 95% of parents felt that toothbrushing charts would be a good way for dentists in practice to encourage children to brush regularly. CONCLUSIONS: The benefit of twice daily toothbrushing on caries development in newly erupted first permanent molar teeth is around 50% compared to brushing once a day or less. Parents' beliefs do influence the likelihood of their children brushing twice a day. Key parts of the intervention programme can be used when children attend general dental practice and would be welcomed by parents.

The effect of NaF and SMFP toothpastes on three-year caries increments in adolescents.

A three-year double blind clinical caries trial was undertaken to compare the anticaries efficacy of three types of active agent, namely sodium fluoride (NaF), sodium monofluorophosphate (SMFP) and the combination of NaF plus sodium trimetaphosphate (TMP), using two fluoride levels (1000 ppm F and 1500 ppm F). The prime objective of the study was to determine whether there was any difference in the anticaries efficacy between NaF and SMFP. The second objective was to assess the effect on caries protection of the incorporation of TMP into a NaF dentifrice formulation. The study was carried out to FDI protocol and involved 4,294 children aged 11-12 years at outset. These participants had been selected from a pool of 6,212 potential subjects on the basis of caries experience and dental eruption pattern. They were stratified by sex, examiner, presence of calculus and caries, and allocated at random to one of the six toothpastes under study. Clinical examinations were carried out at baseline and thereafter annually for 3 years. Bitewing radiographs of a subset of children were taken at baseline and at the end of the study. The outcome measure for the study, DMFS increment, was defined as the increase in caries over three years, taking into account changes occurring on individual tooth surfaces. After three years, clinical-only data for 3,517 children were available for the calculation of caries indices. The mean three-year DMFS increment for subjects using a dentifrice containing NaF alone was 6.4 per cent lower than for those using a dentifrice containing SMFP. The difference between the NaF+TMP users and the SMFP users was 8.1 percent.(ABSTRACT TRUNCATED AT 250 WORDS)

A method to compare four mouthrinses: time to gingivitis level as the primary outcome variable.

BACKGROUND AND AIM: The experimental gingivitis model is a well-established method in comparing the chemical antiplaque activity of agents and products. The aim of the present study was to use time in order to achieve an exit level of bleeding on probing (BOP) as the primary outcome variable. METHODS: The study was a single blind, randomised four treatment parallel group design employing 76 healthy volunteers. The cohort was accepted into the study proper if they achieved a level of /= 50% BOP. Using the baseline and exit BOP, MGI and plaque, a deterioration rate for each parameter was derived and used as the unit of analysis. RESULTS: There were highly significant treatment differences for all three parameters. Paired analyses revealed chlorhexidine was highly significantly more effective than the other rinses for all three parameters. CPC and triclosan were not different from the control for BOP, but CPC was significantly different from the control for MGI and plaque, and triclosan was different from the control for plaque. There were no differences between the CPC and triclosan rinses. CONCLUSIONS: The method achieved the expected result of differentiating between the chlorhexidine and the other rinses. Some modification of the method, primarily to group sizes, should improve specificity. The method has the considerable volunteer appeal of early exit, particularly when allocated to control or low activity treatments for plaque.

The effect of sodium trimetaphosphate on caries: a 3-year clinical toothpaste trial.

The objective of this study was to assess the anticaries efficacy of a toothpaste containing 3% sodium trimetaphosphate (TMP; test) relative to a toothpaste containing no caries-preventive agent (control). The study was designed as a 3-year double-blind caries incidence study involving about 2,500 subjects aged 11 years at baseline. After a clinical examination, subjects were stratified by sex, presence of supragingival calculus and caries status and randomly assigned to either the control or the test group. Clinical examinations then took place at annual intervals. At baseline and at the final examination bite-wing radiographs were taken of subjects not radiographed within the previous 6 months. The change in caries between baseline and the 3-year examination was calculated as DMFS increments. The results showed a statistically significant difference of 8% between the test and control groups (p < 0.05). In subjects brushing twice daily the difference between the test and control group was 11% (p < 0.01). It is concluded that, when used regularly, a toothpaste containing 3% TMP will be effective against caries.

Prevalence of dental caries in Latvian 11- to 15-year-Old children and the enhanced diagnostic yield of temporary tooth separation, FOTI and electronic caries measurement.

The aim of this study was to test the feasibility of employing clinical visual examination at the D(1) (enamel and dentine caries) diagnostic threshold, fibre-optic transillumination (FOTI), elective temporary tooth separation (ETTS) and electronic caries measurement (ECM) in the environment of an epidemiological study or clinical trial. It also aimed to compare the diagnostic yield of these diagnostic aides and methods. The sample consisted of 182 Latvian children, mean age 13.3 years (range = 10.6-15.7). For 12-year-old subjects the mean D(3)MFS was 10.58 (SD 6.05) and the mean D(1)MFS was 19.97 (SD 10.47). The additional diagnostic yield from FOTI examination of approximal sites was 40.0% at the D(1) threshold. The additional apparent yield for ETTS was 52.8% at the D(1) threshold. ETTS detected 38.3% more carious surfaces than FOTI at the D(1) threshold. Conversely 57 surfaces thought to be carious on FOTI examination were judged sound following ETTS. Although the ECM appeared practical to use, it broke early in the trial and the results obtained prior to breakdown appeared inaccurate. In conclusion, all diagnostic methods were feasible under the conditions of an epidemiological study or clinical trial.

Comparison of a conventional and modified tooth stain index.

OBJECTIVES: To evaluate a modified tooth stain index and determine the effect of dietary factors on stain formation. METHODS: At baseline, 182 adult volunteers were given a full oral prophylaxis followed by stain assessment using a modification of the Lobene index. This involved assigning separate scores to the mesial (M) and distal (D) sites of each tooth, in addition to the standard gingival area (G) and tooth body (B). For each site, stain intensity and areas were scored. The sum of (intensity X area) scores was calculated for all sites (GBMD-value) and for the gingival and body sites only (GB-value). The subjects used a standard abrasive dentifrice and a soft toothbrush for 6 weeks. RESULTS: Stain was reassessed and the average increase in GBMD-value was 20.9 (sd=9.9) (buccal aspect) and 29.9 (sd=18.0) (lingual aspect). The corresponding GB-values were 4.4 (sd=4.8) and 12.5 (sd=10.2). The coefficients of variation of the GBMD index values were consistently lower than those of the GB values. Smoking and tea-drinking were found to be the only significant (p<0.001) factors investigated for stain formation. CONCLUSIONS: It is concluded that the modified index may well be advantageous to its conventional counterpart because sites with most visible stain are assessed separately and because it may also offer higher discriminatory power due to a lower coefficient of variation.

Effect of oral care habits on caries in adolescents.

Data on toothbrushing habits were collected during a 3-year caries clinical trial of sodium monofluorophosphate toothpastes in Lanarkshire, Scotland, involving 3,005 schoolchildren of mean age 12.5 years at baseline. Stated normal brushing frequency and oral rinsing method after brushing were recorded. Half the panel indicated they rinsed their mouths after toothbrushing using a beaker. The proportion of the panel brushing once per day or more increased during the trial. Differences in oral habits were observed between the sexes, with 42% of girls and 52% of boys being non-beaker rinsers and 73% of girls, but only 44% of boys, brushing their teeth at least twice per day. Twice-a-day brushers had a consistently lower caries increment than less frequent brushers. This was also seen in the baseline prevalence data, but did not account for all incremental differences noted. Subjects using beakers had consistently higher increments than non-beaker rinsers. Again, this difference could not be explained by variations in baseline prevalence. Differences in the caries increment were also observed between boys and girls, these appearing to be linked both to the cumulative effect of male/female habit variations plus a difference in the baseline caries prevalence. A dose response to the three fluoride levels, i.e 1,000, 1,500, and 2,500 ppm F, was seen for the different habit combinations which again could not be explained by differences in the baseline caries prevalence.

Development of a method in situ to study toothpaste abrasion of dentine. Comparison of 2 products.

BACKGROUND/AIMS: The abrasivity of toothpastes is usually determined using in vitro methods; as such, the clinical significance of the findings is uncertain. The aim of the present study was to develop and evaluate a method in situ to study abrasion of dentine by two toothpastes of different Relative Dentine Abrasivity (RDA). METHOD: The study was a single blind, randomised, 2 way cross over design involving 10 healthy dentate volunteers. Subjects wore an maxillary removable acrylic appliance containing two flat human dentine specimens, taped to expose a window of tissue, from 9 am to 4 pm during the two 10 working day study periods. No food or drink was consumed when the appliance was in place. On five occasions each day, the appliances were removed and the dentine windows brushed ex vivo with the allocated paste for 60 s each. Dentine abrasion at days 5 and 10 was measured using a profilometer. RESULTS: Both toothpastes produced measurable abrasion in all subjects and the depth increased in most subjects between 5 and 10 days. There was significant subject and specimen variation both within and between toothpastes. There was significantly increased abrasion by the toothpaste with the higher RDA value and in mean terms the ratio of abrasion between the two pastes was similar to the ratio of the RDA values. CONCLUSION: The method in situ, already used to study dental hard tissue erosion, appears ideally suitable to study dental abrasion alone and the interaction between aetiological factors involved in tooth wear.

Anti-calculus activity of a toothpaste with microgranules.

OBJECTIVE: The objective of the trial was to determine the efficacy of the proven anticalculus active system (zinc citrate trihydrate [ZCT] and triclosan), when the ZCT is delivered from microgranules incorporated in a silica-based toothpaste containing 1450 ppm F as sodium fluoride. DESIGN: A monadic, single-blind, two phase design clinical trial was used to compare the effect of the test and a negative control fluoridated toothpaste on the formation of supragingival calculus. SUBJECTS AND METHODS: Male and female calculus-forming volunteers, aged 18 or over, were recruited for the study following a 2-week screening phase. All subjects were given a scale and polish of their eight lower anterior teeth at the start of both the pre-test and test phases. Subjects were supplied with a silica-based 1450 F ppm fluoridated toothpaste with no anti-calculus active for use during an 8-week pre-test phase. Calculus was assessed at the end of the pre-test and test phases using the Volpe-Manhold index (VMI). Subjects were stratified according to their pre-test VMI score (8-10, 10.5-12, > 12) and gender and then allocated at random to test or negative control toothpaste groups. Subjects with < 8 mm of calculus were excluded from further participation. MAIN OUTCOME MEASURE: The outcome variable was the mean VMI score for the test and negative control groups. RESULTS: The test toothpaste caused a statistically significant 30% reduction in calculus compared with the control paste after a 13-week use. No adverse events were reported during the study. CONCLUSION: The incorporation of the ZCT in microgranules did not adversely affect the anticalculus activity of the new formulation.