Salivary retention after application of fluoride gel using toothbrush or tray: a crossover trial

Concentration of Fluoride in Saliva After Fluoride Gel Application: A Randomised Clinical Trial

OBJECTIVE

The aim of this randomised clinical trial (RCT) was to assess the concentration of fluoride ions in saliva after applying fluoride gel and to examine the extent to which rinsing the mouth with water affects the content of fluoride ions in saliva as opposed to no rinsing after brushing teeth with gel.

METHODS

This single-blind RCT was conducted amongst a group of students (N = 103) and consisted of a questionnaire, clinical examination, saliva collection, and laboratory analysis. After saliva samples were collected, the students brushed their teeth for 2 minutes with Elmex Gelée (Colgate-Palmolive). Next, saliva was collected after 15 and 60 minutes from Group A (spitting out saliva after brushing) and from Group B (spitting out and rinsing with water after brushing). Statistical analysis was performed using a t test to compare the means between the groups.

RESULTS

Fifteen minutes after brushing, the level of fluoride increased in Group A about 15-fold to 15.33 ± 14.73 ppm and in Group B about 6-fold to 6.19 ± 5.97 ppm (P < .001). After 60 minutes, in Group A it decreased to 1.68 ± 0.83 ppm and in Group B to 0.60 ± 0.37 ppm (P < .001).

CONCLUSIONS

The use of fluoride gel in the absence of mouth rinsing produced significantly higher level and a concentration of fluoride in saliva. A post-gel brushing without rinsing might be suitable for patients at high risk for caries. Hence fruther research on the effect of a mouth rinse after use of fluoride gels is eesential to confirm our findings, and to promulgate evidence-based recommendations.

A Comparison of the Fluoride 'Paint- On' vs Tray Application Techniques for Enamel Remineralisation

BACKGROUND

Fluoride gel treatment is not recommended for children < 6 years old due to its potential toxicity. Hence the aim of this study was to compare the effect of 1.23% acidulated-phosphate fluoride (APF) gel paint-on and the conventional tray application techniques on artificial, deciduous enamel carious lesions embedded on wearable appliances.

METHODS

In a randomised crossover study, the volunteer children (n = 29) wore mandibular removable appliances containing embedded tooth specimens with artificial carious lesions. The volunteers had 3 different treatment protocols: (I) 0.4 mL non-fluoride (control) gel, (II) 0.4 mL paint-on 1.23% APF gel or (III) 5 mL 1.23% APF gel, 4 minutes tray application. After 1 hour, the appliances were removed and the specimens underwent an in vitro, 14 days of pH-cycling. The mean percentage reduction in fluorescence (ΔF, %) at baseline (ΔF0) and after the pH-cycling (ΔF1) were determined using quantitative light-induced fluorescence-digital analysis. The mean ΔΔF (ΔF1-ΔF0) was calculated to compare the differences between groups.

RESULTS

The mean ΔΔF of groups I to III were -1.42 ± 1.49, 1.06 ± 2.11, and 1.12 ± 3.57 and -1.25 ± 1.44, 1.13 ± 1.84 and 1.44 ± 3.62 for the smooth surface and proximal surface lesions, respectively. The mean ΔΔF in the 2 treatment groups were significantly greater compared with the control group (P < .001). There was no significant difference in ΔΔF between the APF gel tray and paint-on groups either in the smooth surfaces, or the proximal surfaces (P = .629 and P = .613, respectively).

CONCLUSION

Our study, for the first time, indicates that the paint-on application of APF gel or the tray application of APF had a similar enamel remineralisation effect. Clinically, this implies that, particularly in younger children, the paint-on application of fluoride is less cumbersome, and possibly more tolerable with a lesser likelihood of fluoride ingestion than the tray application technique.

TRIAL REGISTRATION

Thai Clinical Trial Registry (https://www.thaiclinicaltrials.org/show/TCTR20190724001).

Oral midazolam reduces cortisol levels during local anaesthesia in children: a randomised controlled trial

Little is known about whether midazolam sedation can reduce salivary cortisol levels and consequently influence children's behaviour during dental treatment. The aim of this study was to evaluate the effect of midazolam sedation on salivary cortisol and its correlation with children's behaviour during restorative dental treatment. Eighteen healthy children, aged two to five years, were randomly assigned to two dental treatment appointments, both with physical restraint: oral midazolam 1 mg/kg (MS) and placebo (PS). An observer assessed the children's behaviour (videos) using the Ohio State University Behavioral Rating Scale (OSUBRS). The children's saliva was collected just after waking up, on arrival at the dental school, 25 minutes after local anaesthesia, and 25 minutes after the end of the procedure. Salivary cortisol levels were determined using the enzyme-linked immunoabsorbent assay. The data were analysed by bivariate tests and multivariate analysis of variance (5% level). Salivary cortisol levels were lower in the MS group than in the PS group at the time of anaesthesia (p = 0.004), but did not vary during the appointment within sedation (p = 0.319) or placebo (p = 0.080) groups. Children's behaviour was negative most of the time and did not differ between MS and PS; however, the behaviour (OSUBRS) did not correlate with salivary cortisol levels. Oral midazolam is able to control salivary cortisol levels during dental treatment of pre-schoolers, which might not lead to better clinical behaviour.