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Background: In vivo multiphoton imaging and automatic 3D image processing tools provide quantitative information on human skin constituents. These multiphoton‐based tools allowed evidencing retinoids epidermal effects in the occlusive patch test protocol developed for antiaging products screening. This study aimed at investigating their relevance for non‐invasive, time course assessment of retinoids cutaneous effects under real‐life conditions for one year. Materials and Methods: Thirty women, 55‐65 y, applied either retinol (RO 0.3%) or retinoic acid (RA 0.025%) on one forearm dorsal side versus a control product on the other forearm once a day for 1 year. In vivo multiphoton imaging was performed every three months, and biopsies were taken after 1 year. Epidermal thickness and dermal‐epidermal junction undulation were estimated in 3D with multiphoton and in 2D with histology, whereas global melanin density and its z‐epidermal distribution were estimated using 3D multiphoton image processing tools. Results: Main results after one year were as follows: a) epidermal thickening with RO (+30%); b) slight increase in dermal‐epidermal junction undulation with RO; c) slight decrease in 3D melanin density with RA; d) limitation of the melanin ascent observed with seasonality and time within supra‐basal layers with both retinoids, using multiphoton 3D‐melanin z‐epidermal profile. Conclusions: With a novel 3D descriptor of melanin z‐epidermal distribution, in vivo multiphoton imaging allows demonstrating that daily usage of retinoids counteracts aging by acting not only on epidermal morphology, but also on melanin that is shown to accumulate in the supra‐basal layers with time. [ABSTRACT FROM AUTHOR]

Aim: To compare efficacy of an anhydrous 0.454% w/w stannous fluoride/sodium fluoride toothpaste (Test) versus a sodium monofluorophosphate toothpaste (Negative control) and a stannous chloride/sodium fluoride toothpaste (Positive control) for dentine hypersensitivity relief after 8 weeks' twice‐daily use. Materials and Methods: In this randomized, examiner‐blind, stratified, parallel study, primary and secondary efficacy variables were mean changes in Schiff score (evaporative [air] sensitivity) and tactile threshold (Yeaple probe), respectively, from baseline to Week 8 between Test (n = 62) and Negative control (n = 62). Test and Positive control (n = 61) comparisons were exploratory objectives. Results: All groups significantly improved from baseline on both dentine hypersensitivity measures (p <.0001). Difference between adjusted mean changes from baseline in Schiff sensitivity scores at Week 8 for Test versus Negative control groups was 0.19 (95% CI 0.002, 0.374), in favour of the Negative control (p =.0476; 12.57% difference). Difference in tactile threshold was −7.20 g (95% CI −16.376, 1.975), and this was not statistically significant (p =.3715; −21.83% difference). Test group showed no significant difference versus Positive control for either measure. Toothpastes were generally well tolerated. Conclusion: While twice‐daily use of Test toothpaste significantly reduced dentine hypersensitivity from baseline, there was no significant advantage over negative or positive controls. Study registration: Clinicaltrials.gov; NCT03310268. [ABSTRACT FROM AUTHOR]

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Unlike other oral care products, there are limited technologies in the denture adhesive category with the majority based on polymethyl vinyl ether/maleic anhydride (PVM/MA) polymer. Carbomer‐based denture adhesives are less well studied, and there are few clinical studies directly comparing performance of denture adhesives based on different technologies. This single‐centre, randomised, three‐treatment, three‐period, examiner‐blind, crossover study compared a carbomer‐based denture adhesive (Test adhesive) with a PVM/MA‐based adhesive (Reference adhesive) and no adhesive using incisal bite force measurements (area over baseline over 12 hr; AOB0–12) in participants with a well‐made and at least moderately well‐fitting complete maxillary denture. Eligible participants were randomised to a treatment sequence and bit on a force transducer with increasing force until their maxillary denture dislodged. This procedure was performed prior to treatment application (baseline) and at 0.5, 1, 3, 6, 9, and 12 hr following application. Forty‐four participants were included in the modified intent‐to‐treat population. AOB0–12 favoured both Test adhesive to No adhesive (difference: 2.12 lbs; 95% CI [1.25, 3.00]; p < 0.0001) and Reference adhesive to No adhesive (difference: 2.76 lbs; 95% CI [1.89, 3.63]; p < 0.0001). There was a numerical difference in AOB0–12 for Test versus Reference adhesive (−0.63 lbs; [−1.51, 0.25]); however, this was not statistically significant (p = 0.1555). Treatments were generally well tolerated. Both PVM/MA and carbomer‐based denture adhesives demonstrated statistically significantly superior denture retention compared with no adhesive over 12 hr, with no statistically significant difference between adhesives. [ABSTRACT FROM AUTHOR]

Background The occlusive patch test developed for assessing topical retinoids activity in human skin has been extended as a short-term screening protocol for anti-ageing agents. In this model, biopsies are performed at the end of the occlusion period for morphological and immuno-histochemistry analysis. Multiphoton microscopy is a recent non-invasive imaging technique that combined with image processing tools allows the in vivo quantification of human skin modifications. Objective To validate with gold standards of anti-ageing that are retinoids, the relevance of multiphoton microscopy for kinetic and quantitative assessment in this model. Methods Twenty women, aged 50-65 years, were enrolled. Retinol 0.3% ( RO) and Retinoic acid 0.025% ( RA) were applied to the dorsal photo-damaged side of their forearm under occlusive patches for 12 days. A patch alone was applied to a third area as control. Evaluation was performed at day D0, D12 (end of treatment), D18 and D32 using multiphoton microscopy. Epidermal thickness, normalized area of the dermal-epidermal junction (DEJ) and melanin density were estimated using 3D image processing tools. Results Main significant results are: Epidermal thickening at D12, D18 and D32 with RO and at D12, D18 with RA vs. baseline and vs. control., Increased DEJ undulation at D32 with RO and at D12 with RA vs. baseline and vs. control., Decreased melanin content with RO (at D12 and D18 vs. baseline and at D32 vs. baseline and vs. control) and with RA (at D12 vs. baseline)., Conclusions This study shows that multiphoton microscopy associated to specific 3D image processing tools allows cutaneous effects induced by topical retinoids in this in vivo model to be non-invasively detected, quantified and followed over time. This innovative approach could be applied to the evaluation of other active compounds. [ABSTRACT FROM AUTHOR]