Microbiological and clinical effects of probiotic-related Zeger therapy on gingival health: a randomized controlled clinical trial.

BACKGROUND: This single-blind randomized controlled trial was aimed to evaluate the microbiological and clinical effects of Zeger therapy on gingival health. METHODS: Twenty-four adults with gingivitis were recruited and monitored micro-biologically and clinically at baseline (Day 0), 4 weeks (Day 29) after therapy. All volunteers received one-stage full-mouth supragingival scaling as basic oral health care for baseline, and then randomly divided into experimental (koumiss, n = 12) or control (none, n = 12) group. The koumiss was used once a day for 4 weeks. RESULTS: The microbial diversity of the experimental group increased significantly after drinking koumiss (p < 0.05), mainly owing to increasing of Gram-positive bacteria (p = 0.038) and oral health-related microbes (Rothia, Corynebacterium, Actinomyces, Saccharibacteria_TM7, etc.), decreasing of Gram-negative bacteria (p = 0.009) and periodontal disease-related microbes (Porphyromonas, Fusobacterium, Veillonella, etc.), while the microbial diversity of the control group had no significant change (p > 0.05). However, there was no significant difference between the two groups in the clinical parameters (p > 0.05). CONCLUSIONS: Zeger therapy promotes the diversity of supragingival microbiome in adults with gingivitis and increases the abundance of some beneficial flora while decreasing some harmful without clinical parameters marked changing, which holds promise for improving of gingivitis and may be a valuable oral health care approach in the future. TRIAL REGISTRATION: The clinical trial was approved by the Medical Ethics Committee of West China Hospital of Stomatology, Sichuan University, batch No. WCHSIRB-D-2021-428. Before patient registration began, the prospective clinical trial was registered in www. CLINICALTRIALS: gov public repository in China under the registration number ChiCTR2200060555 on 04/06/2022.

Dynamic microtubules slow down during their shrinkage phase.

Microtubules are dynamic polymers that undergo stochastic transitions between growing and shrinking phases. The structural and chemical properties of these phases remain poorly understood. The transition from growth to shrinkage, termed catastrophe, is not a first-order reaction but rather a multistep process whose frequency increases with the growth time: the microtubule ages as the older microtubule tip becomes more unstable. Aging shows that the growing phase is not a single state but comprises several substates of increasing instability. To investigate whether the shrinking phase is also multistate, we characterized the kinetics of microtubule shrinkage following catastrophe using an in vitro reconstitution assay with purified tubulins. We found that the shrinkage speed is highly variable across microtubules and that the shrinkage speed of individual microtubules slows down over time by as much as several fold. The shrinkage slowdown was observed in both fluorescently labeled and unlabeled microtubules as well as in microtubules polymerized from tubulin purified from different species, suggesting that the shrinkage slowdown is a general property of microtubules. These results indicate that microtubule shrinkage, like catastrophe, is time dependent and that the shrinking microtubule tip passes through a succession of states of increasing stability. We hypothesize that the shrinkage slowdown is due to destabilizing events that took place during growth, which led to multistep catastrophe. This suggests that the aging associated with growth is also manifested during shrinkage, with the older, more unstable growing tip being associated with a faster depolymerizing shrinking tip.

The introduction of team-based learning into the clinical pharmacology section of the endodontics clinical course.

Team-based learning (TBL) has been widely applied and evaluated to produce better student outcomes. TBL has been introduced into the clinical pharmacology section of the endodontics clinical course at the School of Stomatology, Wuhan University since 2021. Here, the teaching experience in this course was summarized. The TBL course consisted of a knowledge assignment, intrateam and interteam discussion, practicing, evaluation, cases discussion and examination. The topics of the TBL class included cavity preparation and filling for treatment of dental caries, disinfection, and shaping and filling of root canal for root canal therapy. A total of 64 students participated in the TBL course. The students completed course work and hands-on practice to the satisfaction of the instructor. Furthermore, most participants held positive attitudes toward the TBL course because TBL provided the opportunity for teamwork to enable them to acquire and understand the therapeutic drug and material more quickly and made them more confident in the following practice. Our experience suggested that the application of the TBL contributed to the authentic practice of the endodontics clinical course.

A Novel Drug Delivery System: the Encapsulation of Naringenin in Metal-Organic Frameworks into Liposomes.

Poorly water-soluble naringenin (NAR) was selected as a model drug and loaded into the porous MOFs for the construction of NAR@ZIF-8 inclusion complex. By film dispersion method, NAR@ZIF-8 was further encapsulated into liposomes to fabricate a novel drug delivery system. Liposomes and a novel drug delivery system were established. Subsequently, the lipid-drug ratio, phospholipid-cholesterol ratio, and hydration temperature were investigated using the Box-Behnken design based the single factor experiment. The prepared liposomes system showed spherical or quasi-spherical shape, uniform particle size distribution, and complete structure. More specifically, the average particle size was 113.2 ± 1.4 nm, and zeta potential was - 7.536 ± 0.264 mV. Moreover, the drug release behaviors of NAR, NAR@ZIF-8, and NAR@ZIF-8 liposomes were explored in vitro. Compared with free NAR and NAR@ZIF-8 which exhibited a burst drug release, NAR@ZIF-8 liposomes showed a more sustained release behavior with 79.86% drug release in 72 h. In vitro cytotoxicity experiments showed that, compared with free NAR and NAR@ZIF-8, NAR@ZIF-8 liposomes exhibited higher inhibition efficiency on lung adenocarcinoma A549 cells and gastric cancer SGC-7901 cells in a concentration-dependent manner.

Glutathione and Reactive Oxygen Species Dual-Responsive Block Copolymer Prodrugs for Boosting Tumor Site-Specific Drug Release and Enhanced Antitumor Efficacy.

A remarkable hallmark of cancer cells is the heterogeneous coexistence of overproduced intracellular glutathione (GSH) and a high level of reactive oxygen species (ROS) compared with those in normal cells, which have been frequently used as the stimuli to trigger drug release from the nanocarriers. Most of the stimuli-responsive delivery vehicles have been designed to respond to only one redox stimulus (e.g., GSH or ROS). Herein, we develop a GSH and ROS dual-responsive amphiphilic diblock copolymer prodrug (BCP) (GR-BCP) consisting of poly(ethylene glycol) (PEG)- and camptothecin (CPT)-conjugated poly(methacrylate) in the side chains via thioether bonds. In comparison, GSH or ROS single-responsive BCPs (G-BCPs or R-BCPs) were prepared, where CPT drugs were linked by disulfide or thioketal bonds, respectively. The three BCPs can form well-defined spherical micellar nanoparticles in an aqueous solution with a diameter of ∼50 nm. Compared with G-BCP and R-BCP, GR-BCP realized the highest cytotoxicity against HeLa cells with the half-inhibitory concentration (IC50) of 6.3 µM, which is much lower than 17.8 µM for G-BCP and 28.9 µM for R-BCP. Moreover, for in vivo antitumor performance, G-BCP, R-BCP, and GR-BCP showed similar efficiencies in blood circulation and tumor accumulation after intravenous injection. However, GR-BCP realized the most efficient tumor suppression with few side effects. Our findings demonstrate that intracellular GSH and ROS dual-responsive BCPs show a more efficient responsive drug release inside tumor cells for boosting the antitumor efficacy as compared with GSH or ROS single-responsive BCPs, which provides novel strategies for designing redox-responsive BCPs.

Removal and recovery of silver nanoparticles by hierarchical mesoporous calcite: Performance, mechanism, and sustainable application.

The widespread use of silver nanoparticles (AgNPs) inevitably leads to the environmental release of AgNPs. The released AgNPs can pose ecological risks because of their specific toxicity. However, they can also be used as secondary sources of silver metal. Herein, hierarchical mesoporous calcite (HMC) was prepared and used to remove and recover AgNPs from an aqueous solution. The batch experiments show that the HMC has high removal percentages for polyvinylpyrrolidone- and poly (vinyl alcohol)-coated AgNPs (PVP- and PVA-AgNPs) over a wide pH range of 6-10. The adsorption isotherms indicate that the maximum removal capacities are 55 and 19 mg g-1 for PVP-AgNPs and PVA-AgNPs, respectively, corresponding to partition coefficients (PCs) of 0.55 and 0.77 mg g-1 µM-1. Furthermore, the removal performance is also not impaired by coexisting anions, such as Cl-, NO3-, SO42-, and CO32-. Their removal mechanisms can be ascribed to the electrostatic attraction and chemical adsorption between the HMC and polymer-coated AgNPs. Calcium ions on the HMC surface serve as active sites for coordination with the oxygen-bearing functional groups of AgNP coatings. Moreover, the AgNPs adsorbed onto HMC show high catalytic activity and good reusability for the reduction of the organic pollutant 4-nitrophenol. This work may pave the way not only to remove metal nanopollutants from waters but also to convert them into functional materials.

Brick tea consumption is a risk factor for dental caries and dental fluorosis among 12-year-old Tibetan children in Ganzi.

Brick tea contains high concentration of fluoride. The aim of the present work was to explore whether and how the brick tea is a risk factor for dental caries and dental fluorosis among Tibetan children in Ganzi. A cross-sectional study was conducted with 368 12-year-old Tibetan children in Ganzi. Dental caries was measured by DMFT index, and dental fluorosis severity was measured by Dean's Index. Community Fluorosis Index was used to estimate public health significance of dental fluorosis. Oral health-related behaviors and awareness, dietary habits and socioeconomic status were determined by a questionnaire. Bivariate and multivariate analyses were used to determine risk factors associated with dental caries and dental fluorosis. Dental caries prevalence was 37.50%, mean DMFT was 0.84 ± 1.53, while dental fluorosis prevalence was 62.23%. Community Fluorosis Index was 1.35, indicating a medium prevalent strength of dental fluorosis. Dental fluorosis was associated with mother's regular consumption of brick tea and residence altitude, and dental caries was associated with mother's regular consumption of brick tea. Mother's regular consumption of brick tea was a risk factor for both dental fluorosis and dental caries among children. Reducing mother's brick tea consumption during pregnancy and lactation may improve oral health status of their children.

Multifunctional Polymeric Micelles with Amplified Fenton Reaction for Tumor Ablation.

Relative to normal cells, tumor cells lack adequate capability of reactive oxygen scavenging. Thus, tumor cells can be selectively killed by increasing the concentration of reactive oxygen species in tumor tissue. In this report, we construct an integrated multifunctional polymeric nanoparticle which can selectively improve hydrogen peroxide (H2O2) levels in tumor tissue and convert them into more active hydroxyl radicals by Fenton reaction. First, the diblock copolymers containing polyethylene glycol (PEG) and poly(glutamic acid) modified by ß-cyclodextrin (ß-CD) were synthesized. The block copolymer, ferrocenecarboxylic acid hexadecyl ester (DFc), and ascorbyl palmitate (PA) were coassembled in aqueous solution to obtain stable core-shell micelles through the inclusion complexation between ß-CD moieties in the block copolymer and ferrocene (Fc) groups from DFc. After intravenous injection, the particles achieved significant accumulation in tumor tissue where ascorbic acid at the pharmacological concentration promotes the production of H2O2, and subsequently Fenton reaction was catalyzed by Fc groups to produce hydroxyl radicals to efficiently kill cancer cells and suppress tumor growth. The micellar systems possess great potentials toward cancer therapy through synergistic H2O2 production and conversion into hydroxyl radicals specifically in tumor tissue.

Socio-demographic factors, dental status and health-related behaviors associated with geriatric oral health-related quality of life in Southwestern China.

BACKGROUND: The aging of Chinese society has increased interest in improving the health-related quality of life (HRQoL) of the elderly, including their oral health-related quality of life (OHRQoL). This study aims to evaluate the OHRQoL of elders living in Sichuan Province (China) and to explore the explanatory factors of their OHRQoL. METHODS: A cross-sectional study conducted in 2016 in the Sichuan Province analyzed data from 744 elders, aged 65 to 74 years (mean age 69.3, 51.3% female). Clinical examinations and questionnaires were completed to collect information on the participants' socio-demographic characteristics, health-related behaviors, dental status, subjective health conditions and General Oral Health Assessment Index (GOHAI) score. RESULTS: The mean GOHAI score was 48.23 (SD 7.62), and the median score was 49. After adjustment for age and gender, the multiple linear regression analysis showed that participants who were female, had fair or poor self-rated oral health, decayed, missing and filled teeth (DMFT) score ≥ 20, fair or poor self-rated general health, and ≥ 2 teeth with root caries had worse OHRQoL, and participants who were edentulous had better OHRQoL (F = 29.58, p < 0.001). CONCLUSION: The OHRQoL of the elders living in Sichuan Province was relatively good. The explanatory variables were gender; self-rated oral health; DMFT score; self-rated general health; number of natural teeth; and number of teeth with root caries. More attention should be paid to caries status and retention of healthy teeth to improve the OHRQoL of elders in Sichuan Province, preserving a healthy mouth contributes to better OHRQoL.

Therapeutic Vesicular Nanoreactors with Tumor-Specific Activation and Self-Destruction for Synergistic Tumor Ablation.

Polymeric nanoreactors (NRs) have distinct advantages to improve chemical reaction efficiency, but the in vivo applications are limited by lack of tissue-specificity. Herein, novel glucose oxidase (GOD)-loaded therapeutic vesicular NRs (theraNR) are constructed based on a diblock copolymer containing poly(ethylene glycol) (PEG) and copolymerized phenylboronic ester or piperidine-functionalized methacrylate (P(PBEM-co-PEM)). Upon systemic injection, theraNR are inactive in normal tissues. At a tumor site, theraNR are specifically activated by the tumor acidity via improved permeability of the membranes. Hydrogen peroxide (H2 O2 ) production by the catalysis of GOD in theraNR increases tumor oxidative stress significantly. Meanwhile, high levels of H2 O2 induce self-destruction of theraNR releasing quinone methide (QM) to deplete glutathione and suppress the antioxidant ability of cancer cells. Finally, theraNR efficiently kill cancer cells and ablate tumors via the synergistic effect.

Modular Design and Facile Synthesis of Enzyme-Responsive Peptide-Linked Block Copolymers for Efficient Delivery of Doxorubicin.

Construction of efficient doxorubicin (DOX) delivery systems addressing a cascade of physiological barriers remains a great challenge for better therapeutic efficacy of tumors. Herein, we design well-defined enzyme-responsive peptide-linked block copolymer, PEG-GPLGVRGDG-P(BLA-co-Asp) [PEG and P(BLA-co-Asp) are poly(ethylene glycol) and partially hydrolyzed poly(ß-benzyl l-aspartate) (PBLA), respectively] (P3), with modular functionality for efficient delivery of DOX. The block copolymers were successfully obtained via click reaction to introduce peptide (alkynyl-GPLGVRGDG) into the end of PEG for initiating ring-opening polymerization of ß-benzyl l-aspartate N-carboxyanhydride (BLA-NCA) by terminal amino groups followed by partial hydrolysis of PBLA segments. P3 micelle was demonstrated to encapsulate DOX efficiently through synergistic effect of benzyl group-based hydrophobic and carboxyl moiety-based electrostatic interactions. Effective matrix metalloproteinase-2 (MMP-2)-triggered cleavage of peptide for dePEGylation of P3 micelles was confirmed and residual RGD ligands were retained on the surfaces. Against HT1080 cells overexpressing MMP-2, DOX-loaded P3 micelles showed approximately 4-fold increase of the cellular internalization amount as compared with free DOX and half maximal inhibitory concentration (IC50) value of DOX-loaded P3 micelles was determined to be 0.38 µg/mL compared with 0.66 µg/mL of free DOX due to MMP-triggered dePEGylation, RGD-mediated cellular uptake, and rapid drug release inside cells. Binding and penetration evaluation toward HT1080 multicellular tumor spheroids (MCTs) confirmed high affinity and deep penetration of P3 micelles in tumor tissues. This modular design of enzyme-responsive block copolymers represents an effective strategy to construct intelligent drug delivery vehicles for addressing a cascade of delivery barriers.

Comparative assessment of fluoride varnish and fluoride film for remineralization of postorthodontic white spot lesions in adolescents and adults over a 6-month period: A single-center, randomized controlled clinical trial.

INTRODUCTION: The objective of this 3-arm parallel randomized trial was to evaluate the effects of a fluoride varnish and a fluoride film on the remineralization of white spot lesions around orthodontic brackets after orthodontic treatment. METHODS: Patients who had recently completed orthodontic treatment were randomly assigned to the varnish, film, and control groups. Eligibility criteria included age of 12 to 25 years, good general health, and at least 1 maxillary anterior tooth with a white spot lesion. The primary outcome was the decrease in the lesion volume of each patient after 6 months of treatment; fluorescence loss and area were the secondary outcome measures. Randomization was accomplished according to a computer-generated randomization schedule, and allocation concealment was achieved with nontransparent concealed envelopes. Blinding was applicable for the treatments only. The test groups received fluoride varnish or film treatment once a month for 6 months, and the control group received a placebo treatment. All patients received oral hygiene education and were required to use fluoride toothpaste daily. Quantitative light-induced fluorescence images were taken at baseline and at the 3-month and 6-month follow-ups. A mixed-effects linear model was used to analyze quantitative light-induced fluorescence parameters with confounders integrated into the model. RESULT: Two hundred forty patients (mean age, 16.9 years; range, 12-25 years) with 597 teeth with a white spot lesion were randomized 1:1:1 to the varnish, film, and control groups. Baseline demographics were similar between groups, and 29 patients were lost to follow-up. The primary analysis was carried out on a per-protocol basis involving 72 patients in the control group, 69 patients in the varnish group, and 70 patients in the film group who completed the study. The product of fluorescence loss and lesion area values were statistically associated with time (estimate, -4.58; 95% confidence interval [CI], -5.84 to -3.31; P <0.0001), and a significant decrease in the product of fluorescence loss and lesion area was observed in all groups after 6 months with each treatment. The interaction between group and time in the statistical analysis indicated that the product of fluorescence loss and lesion area values of the 3 groups followed different trends over time. Further pair-wise comparisons showed that the decreases in the 2 test groups were significantly greater than those in the control group (varnish vs control: estimate, -11.83; 95% CI, -15.39 to -8.26; P <0.0001; film vs control, estimate: -7.72; 95% CI, -11.34 to 4.10; P <0.0001) in the analysis for 6 months. In addition, the decrease in the varnish group was significantly greater than that in the film group (estimate, 4.11; 95% CI, 0.48 to 7.73; P = 0.0266) in the analysis for 6 months. No serious adverse effects associated with the use of the tested varnish, film, or placebo occurred. CONCLUSIONS: After removal of the orthodontic brackets, some natural remineralization of white spot lesions occurred, and daily use of fluoride toothpaste may be helpful for this process. However, not all patients experienced this remineralization, and treatment with fluoride varnish or fluoride film induced greater remineralization of white spot lesions. In addition, our results suggest that fluoride varnish may be slightly more effective than fluoride film. However, further similar clinical trials with more patients are needed to definitively determine which fluoride treatment is most effective. REGISTRATION: This trial was registered on the Chinese Clinical Trial Register, number ChiCTR-TRC-13003764. PROTOCOL: The details of the trial protocol are posted online at: http://apps.who.int/trialsearch/Trial.aspx?TrialID=ChiCTR-TRC-13003764.

Evaluation of Fluorescence Imaging with Reflectance Enhancement (FIRE) for Quantifying Enamel Demineralization In vitro.

OBJECTIVES: To assess the ability of fluorescence imaging with reflectance enhancement (FIRE) to quantify early enamel demineralization in vitro. METHODS: A total of 30 bovine enamel specimens were immersed in demineralizing solution to produce artificial caries. Specimens were examined by FIRE, quantitative light-induced fluorescence (QLF), and polarized light microscopy (PLM) at baseline and after 0.5, 1, 2, 4, 8, 24, 48 and 72 h of immersion. Fluorescence loss measured by FIRE and QLF was compared with lesion depth measurements by PLM. RESULTS: Over all time points, measurement of fluorescence loss by FIRE correlated well with the measurement of x0394;F by QLF and of x0394;Q by QLF. Both FIRE and QLF techniques showed significant correlation with PLM. CONCLUSION: FIRE technology may be useful for quantifying enamel demineralization in vitro.

Phylogeographical analysis of a cold-temperate freshwater fish, the Amur sleeper (Perccottus glenii) in the Amur and Liaohe River basins of Northeast Asia.

The Amur sleeper Perccottus glenii (Perciformes, Gobioidei, Odontobutidae) is well known as an invasive fish in the river basins of Eastern and Central Europe, but its genetic background is unavailable across its native habitats in northeast Asia. In this study, we used the mitochondrial cytochrome b gene by sampling 19 populations of P. glenii across its native distributional areas of Liaohe and Amur River basins to explore its evolutionary history. Phylogenetic analyses identified three major clades within P. glenii, among which Clade A and Clade B were co-distributed in the Liaohe and Amur River basins, and Clade C was restricted to the latter. Molecular dating showed that the splits of Clades A, B and C have happened in the late Early-early Middle Pleistocene and the most recent common ancestors of these clades have been presented in the late Middle-early Late Pleistocene. The P. glenii showed very high levels of genetic structure among populations (ΦST = 0.801), probably due to the characters of its life histories with very limited dispersal ability. The admixture of different clades in some populations of P. glenii probably reflects historical secondary contact. These findings indicate that Pleistocene climatic oscillation and river capture were major determinants for genetic variations and evolutionary history of the P. glenii.

Remineralization of early caries by chewing sugar-free gum: a clinical study using quantitative light-induced fluorescence.

PURPOSE: To determine whether sugar-free gum can provide remineralization and caries control of active enamel caries lesions compared to baseline (before gum chewing) and to a no-gum group, following daily chewing for 12 weeks by school children; to determine whether chewing frequency can affect the extent of remineralization. METHOD: A pragmatic cluster-randomized controlled clinical trial with schools as the unit of randomization was employed. Three schools in Chengdu, PR China comprised the clusters. The study was approved by the Internal Review Board of Sichuan University. 177 school children, 8-13 years old, with at least one visible white-spot lesion were enrolled in the study. Each of the three clusters was randomly assigned to one of three groups: (1) no gum; (2) chew 2 pieces of sugar-free gum for 20 minutes, 3x per day; (3) chew 2 pieces of sugar-free gum for 12 minutes, 5x per day. White-spot lesions were examined by quantitative light-induced fluorescence (QLF) at baseline and after 4, 8, and 12 weeks of treatment. RESULTS: 155 subjects completed the study. Of them, the mean values of fluorescence loss at baseline were 9.52, 9.83 and 9.17 for no-gum group, 3x per day group and 5x per day group, respectively. For the area, the mean values at baseline were 2.52, 2.61 and 2.57 mm2 for no-gum group, 3x per day group and 5x per day group, respectively. For AQ, the mean values at baseline were -27.91, -28.29 and -29.67 for no-gum group, 3x per day group and 5x per day group, respectively. To adjust for differences in groups at baseline, ANCOVA was used. After 12-weeks, for all QLF metrics, the absolute values of 5x per day group were the lowest and the no gum group was the highest; the differences among three groups were statistically significant (P < 0.05). For AQ, which was accepted as the most useful metrics of QLF system, the adjusted mean values at 12 weeks were -26.35, -19.81 and -17.58 for no-gum group, 3x per day group and 5x per day group, respectively. There were significant differences between groups.

Efficacy of a novel dentifrice containing bioactive glass-ceramic for dentinal hypersensitivity: A double-blind randomized controlled trial in Chinese adults.

OBJECTIVE: To assess the efficacy and safety of a toothpaste containing 7.5 % HX-BGC in combating dentinal hypersensitivity. METHODS: A single-center, randomized, double-blind, three-group parallel-controlled design was employed, with Schiff Index and Yeaple Index as measurement indicators. The study evaluated the effectiveness of HX-BGC toothpaste, NovaMin toothpaste, and a negative control toothpaste without desensitizing agents. Eligible subjects underwent baseline examination after a 2-week washout period, and those meeting inclusion criteria and not meeting exclusion criteria entered the study. Participants were randomly assigned to use one of the three toothpastes. Follow-up examinations were conducted immediately after a single use and at 2, 4, and 6 weeks. Intra-group and inter-group comparisons were made for Schiff and Yeaple indices. Safety of the experimental toothpastes was assessed through participant feedbacks and oral soft tissue examinations. RESULTS: Subjects in the three groups were balanced in terms of age and gender distribution, with no baseline differences in indicators. Immediately after a single application of toothpaste, Yeaple indices increased, and Schiff indices decreased, with no significant differences among the groups. After 2 weeks of continuous use, Yeaple indices increased in all groups, with significant differences observed between the HX-BGC group and the other two groups. Schiff indices decreased in all groups, with the NovaMin group showing significant differences compared to the negative control group. At weeks 4 and 6, both indices in the HX-BGC group and the NovaMin group were significantly better than those in the negative control group, with the HX-BGC group outperforming the NovaMin group in the Yeaple index. No serious adverse reactions related to the study products were observed or reported by any participants. CLINICAL SIGNIFICANCE: This clinical trial confirmed the efficacy of HX-BGC in anti-dentinal hypersensitivity and supported the clinical application of the dentifrice containing HX-BGC. CONCLUSION: Compared to the negative control group, both HX-BGC and NovaMin toothpaste groups demonstrated more significant effects in combating dentinal hypersensitivity. No adverse reactions related to the experimental toothpastes were observed.

ACP-Mediated Phase Transformation for Collagen Mineralization: A New Understanding of the Mechanism.

Despite significant efforts utilizing advanced technologies, the contentious debate surrounding the intricate mechanism underlying collagen fibril mineralization, particularly with regard to amorphous precursor infiltration and phase transformation, persists. This work proposes an amorphous calcium phosphate (ACP)-mediated pathway for collagen fibril mineralization and utilizing stochastic optical reconstruction microscopy technology, and has experimentally confirmed for the first time that the ACP nanoparticles can infiltrate inside collagen fibrils. Subsequently, the ACP-mediated phase transformation occurs within collagen fibrils to form HAP crystallites, and significantly enhances the mechanical properties of the mineralized collagen fibrils compared to those achieved by the calcium phosphate ion (CPI)-mediated mineralization and resembles the natural counterpart. Furthermore, demineralized dentin can be effectively remineralized through ACP-mediated mineralization, leading to complete restoration of its mechanical properties. This work provides a new paradigm of collagen mineralization via particle-mediated phase transformation, deepens the understanding of the mechanism behind the mineralization of collagen fibrils, and offers a new strategy for hard tissue repair.

A structural color hydrogel for diagnosis of halitosis and screening of periodontitis.

Oral pathogens can produce volatile sulfur compounds (VSCs), which is the main reason for halitosis and indicates the risk of periodontitis. High-sensitivity detection of exhaled VSCs is urgently desired for promoting the point-of-care testing (POCT) of halitosis and screening of periodontitis. However, current detection methods often require bulky and costly instruments, as well as professional training, making them impractical for widespread detection. Here, a structural color hydrogel for naked-eye detection of exhaled VSCs is presented. VSCs can reduce disulfide bonds within the network, leading to expansion of the hydrogel and thus change of the structural color. A linear detection range of 0-1 ppm with a detection limit of 61 ppb can be achieved, covering the typical VSC concentration in the breath of patients with periodontitis. Furthermore, visual and in situ monitoring of Porphyromonas gingivalis responsible for periodontitis can be realized. By integrating the hydrogels into a sensor array, the oral health conditions of patients with halitosis can be evaluated and distinguished, offering risk assessment of periodontitis. Combined with a smartphone capable of color analysis, POCT of VSCs can be achieved, providing an approach for the monitoring of halitosis and screening of periodontitis.

Self-Healing Hydrogel Containing Decellularized Liver Matrix and Endothelial Cell-Covered Hepatocyte Spheroids for Rescue of Injured Hepatocytes.

Liver fibrosis occurs in many chronic liver diseases, while severe fibrosis can lead to liver failure. A chitosan-phenol based self-healing hydrogel (CP) integrated with decellularized liver matrix (DLM) is proposed in this study as a 3D gel matrix to carry hepatocytes for possible therapy of liver fibrosis. To mimic the physiological liver microenvironment, DLM is extracted from pigs and mixed with CP hydrogel to generate DLM-CP self-healing hydrogel. Hepatocyte spheroids coated with endothelial cells (ECs) are fabricated using a customized method and embedded in the hydrogel. Hepatocytes injured by exposure to CCl4-containing medium are used as the in vitro toxin-mediated liver fibrosis model, where the EC-covered hepatocyte spheroids embedded in the hydrogel are co-cultured with the injured hepatocytes. The urea synthesis of the injured hepatocytes reaches 91% of the normal level after 7 days of co-culture, indicating that the hepatic function of injured hepatocytes is rescued by the hybrid spheroid-laden DLM-CP hydrogel. Moreover, the relative lactate dehydrogenase activity of the injured hepatocytes is decreased 49% by the hybrid spheroid-laden DLM-CP hydrogel after 7 days of co-culture, suggesting reduced damage in the injured hepatocytes. The combination of hepatocyte/EC hybrid spheroids and DLM-CP hydrogel presents a promising therapeutic strategy for hepatic fibrosis.

Clinical investigation of oral malodor during long-term use of arginine-containing dentifrices.

PURPOSE: To investigate whether the long term use of two dentifrices containing arginine, an insoluble calcium compound, and fluoride: (1) 1.5% arginine and 1450 ppm F as sodium monofluorophosphate (NaMFP) in a dicalcium phosphate dihydrate (dical) base, and (2) 8.0% arginine and 1450 ppm F as NaMFP in a calcium carbonate base, results in an increase in oral malodor potentially associated with increased ammonia production from breakdown of arginine, as compared to a commercially available fluoride dentifrice without arginine (1450 ppm F as NaMFP in a dical base), after 6 months of product use. METHODS: A 6-month clinical study, with 119 subjects, was conducted in Chengdu, China, using a double blind, randomized, parallel, three-treatment design. A panel of four expert judges used a nine-point hedonic scale to evaluate breath odor using a protocol designed in concordance with the ADA Acceptance Program Guidelines for Product Used in the Management of Oral Malodor. After a baseline evaluation, study subjects who scored above the threshold value for unpleasant breath odor were stratified by score and randomized into one of three treatment groups. Subjects were provided with a soft-bristled manual toothbrush (Colgate Classic Clean Toothbrush) and brushed their teeth thoroughly in their regular and customary manner for 1 minute with their assigned dentifrice, twice daily. Before breath-odor evaluations, the subjects refrained from eating odorigenic foods and did not use dental hygiene procedures, breath mints, or mouth rinses for 48 hours and 12 hours, respectively. RESULTS: There was no statistically significant difference in oral malodor levels among subjects using the three dentifrices after 1, 3 and 6 months of product use.