Clinical efficacy of a novel radiofrequency toothbrush for tooth stain reduction and tooth whitening: A randomized controlled trial.

BACKGROUND: The authors aimed to evaluate the effect of a novel radiofrequency (RF) toothbrush on tooth stains and shades compared with a sonic vibrating toothbrush (CVS Health SmileSonic Pro Advanced Clean Sonic Toothbrush, Ranir) that earned the American Dental Association Seal of Acceptance. METHODS: The authors conducted a single-blind prospective study over 6 weeks. Participants were randomized to 1 of 2 study groups to receive either an RF toothbrush (ToothWave, Home Skinovations [test]) or a sonic vibrating toothbrush (SmileSonic powered toothbrush, Ranir [control]) and performed twice-daily toothbrushing with fluoridated toothpaste (Crest Cavity Protection, Procter & Gamble) for 6 weeks. Tooth stains and shades were assessed using the Lobene Stain Index and VITA Bleachedguide 3D-MASTER shade guide (VITA North America) at baseline and after 4 and 6 weeks of toothbrushing. In addition, the VITA Easyshade Advance 4.0 spectrophotometer (VITA North America) was used for shade evaluation. Safety was evaluated by means of oral soft-tissue examinations at each visit. Percentage reduction from baseline was compared between the groups. Statistical analyses were conducted using Mann-Whitney nonparametric model. RESULTS: Eighty-six participants (43 in each group) completed the study with fully evaluable data. At baseline, the groups did not differ significantly in mean measurement scores. Percentage reductions of the measured scores were significantly greater (more extrinsic stain removal and whitening) in the test group than in the control group (P < .001). Both toothbrushes were well-tolerated, and no device-related adverse events were reported during the study. CONCLUSIONS: The RF toothbrush produced substantial benefits in the reduction of tooth stains and whitening of tooth shade compared with a powered toothbrush (CVS Health SmileSonic Pro Advanced Clean Sonic Toothbrush, Ranir) that earned the American Dental Association Seal of Acceptance. PRACTICAL IMPLICATIONS: The novel RF toothbrush is a safe and effective tool for stain removal and tooth whitening and can serve as an alternative to other whitening agents. This clinical trial was registered at ClinicalTrials.gov. The registration number is NCT03885609.

Anti-caries evaluation of a nano-hydroxyapatite dental lotion for use after toothbrushing: An in situ study.

OBJECTIVES: The aim of this randomized, double-blind, two-arm crossover in situ study was to investigate whether nano-hydroxyapatite (nanoHAP) dental lotion (Apagard Deep Care) applied immediately after tooth-brushing with nanoHAP toothpaste (Apagard M-plus) enhances the remineralization promotion and the demineralization inhibition efficacies of nanoHAP toothpastes. METHODS: 64 sound enamel blocks and 64 blocks bearing artificially-produced initial caries were produced from human permanent molar teeth. During each treatment period, lasting 14 days per arm, two blocks, one sound and one lesion-bearing, were exposed to either 5% nanoHAP-containing or placebo dental lotion after tooth-brushing with 5% nanoHAP toothpaste, via an intra-oral appliance worn by 30 adults in each of the study groups. Baseline and post-test mineral loss were quantified using transverse microradiography (TMR). One-sided t-test of one group mean was used for intragroup comparison, while two-sided t-test of two independent means was used to compare the two dental lotions. RESULTS: Pairwise comparison (baseline vs. post-test) indicated significant (p<.001) remineralization by nanoHAP toothpaste in both groups. However, when compared against each other, there was a significantly (p<.001) greater percentage of remineralization with nanoHAP lotion [58.4(±1.8)%] than with placebo lotion [37.7(±2.2)%]. TMR examination showed absolute demineralization inhibition in sound enamel blocks exposed to either lotions. CONCLUSIONS: Toothpaste containing 5% nanoHAP effectively remineralized initial caries and inhibited demineralization of healthy enamel; however, the application of a dental lotion containing 5% nanoHAP after brushing resulted in superior remineralization compared to a placebo lotion. CLINICAL SIGNIFICANCE: Dental lotion containing 5% nanohydroxyapatite used immediately after toothbrushing with 5% nanohydroxyapatite toothpaste can serve as an adjunct to enhance the clinical benefits of the toothpaste.

The Potential of Hydroxyapatite Toothpaste to Prevent Root Caries: A pH-Cycling Study.

PURPOSE: The effectiveness of a hydroxyapatite (HAP) toothpaste and a fluoride toothpaste in preventing root tissue demineralization (root caries) was compared using an established pH-cycling caries model. MATERIALS AND METHODS: Sixty dentin blocks were produced from the root tissue of extracted human teeth and were assigned to 3 test groups (n=20/group): 10% hydroxyapatite toothpaste (HAP), 1450 ppm fluoride toothpaste (fluoride), and artificial saliva (artsaliva). Early root caries lesions were developed in each sample by 7-day demineralization using a pH-cycling caries model. The daily cyclic treatment regimen consists of two 2-minute toothpaste-slurry treatment periods, one 6-hour acid challenge using acidified gel (pH 4.5), and then storage in remineralizing solution (artsaliva) for the rest of the time. Demineralization was assessed as the amount of mineral loss (∆z) using transverse microradiography (TMR). Pairwise comparisons (between treatments) were performed using analysis of variance (ANOVA), and then Tukey's HSD for multiple comparisons. All p-values are considered significant if p<0.05. RESULTS: Both ANOVA and Tukey's HSD indicated no significant (ANOVA; n=20) difference in mean ∆z among the groups, with least ∆z (±Sd) in the HAP (1117±366) compared to fluoride (1392±334) and artsaliva (1406±223). Relative to control, HAP and fluoride inhibited root demineralization by 21% and 6%, respectively. CONCLUSION: Within the limit of the present study, the tested toothpaste containing 10% HAP is an effective root caries control toothpaste. Toothpaste containing 10% HAP was slightly more effective in preventing tooth demineralization than 1450 ppm fluoride provided as sodium fluoride. Thus, this study shows that HAP toothpastes can serve as an effective alternative to fluoride toothpastes for root caries management.

Comparative efficacy of a hydroxyapatite and a fluoride toothpaste for prevention and remineralization of dental caries in children.

OBJECTIVE: This in situ study compared the effectiveness of two toothpastes containing hydroxyapatite or 500 ppm fluoride in promoting remineralization and inhibiting caries development. MATERIALS AND METHODS: Two enamel blocks (human primary teeth), one sound and one with artificially-produced caries lesion, were exposed to toothpaste containing either 10% hydroxyapatite or 500 ppm F- (amine fluoride) via intra-oral appliance worn by 30 adults in two-arm double blind randomized crossover study lasting 14 days per arm (ClinicalTrials.gov: NCT03681340). Baseline and post-test mineral loss and lesion depth (LD) were quantified using microradiography. One-sided t-test of one group mean was used for intragroup comparison (baseline vs. post-test), while two-sided t-test of two independent means was used to compare the two toothpaste groups. RESULTS: Pairwise comparison (baseline vs. test) indicated significant (p < 0.0001) remineralization and LD reduction by either toothpaste; however, when compared against each other, there was no statistically significant difference in remineralization or LD reduction between the two toothpastes. No demineralization could be observed in sound enamel blocks exposed to either toothpaste. While F- induced lesion surface lamination, HAP produced a more homogenous lesion remineralization. CONCLUSIONS: 10% hydroxyapatite achieved comparable efficacy with 500 ppm F- in remineralizing initial caries and preventing demineralization. Thus the HAP toothpaste is confirmed to be equal to the fluoride toothpaste in this study.

The nuclear experience of CPEB: implications for RNA processing and translational control.

CPEB is a sequence-specific RNA binding protein that promotes polyadenylation-induced translation in early development, during cell cycle progression and cellular senescence, and following neuronal synapse stimulation. It controls polyadenylation and translation through other interacting molecules, most notably the poly(A) polymerase Gld2, the deadenylating enzyme PARN, and the eIF4E-binding protein Maskin. Here, we report that CPEB shuttles between the nucleus and cytoplasm and that its export occurs via the CRM1-dependent pathway. In the nucleus of Xenopus oocytes, CPEB associates with lampbrush chromosomes and several proteins involved in nuclear RNA processing. CPEB also interacts with Maskin in the nucleus as well as with CPE-containing mRNAs. Although the CPE does not regulate mRNA export, it influences the degree to which mRNAs are translationally repressed in the cytoplasm. Moreover, CPEB directly or indirectly mediates the alternative splicing of at least one pre-mRNA in mouse embryo fibroblasts as well as certain mouse tissues. We propose that CPEB, together with Maskin, binds mRNA in the nucleus to ensure tight translational repression upon export to the cytoplasm. In addition, we propose that nuclear CPEB regulates specific pre-mRNA alternative splicing.