The distribution of oral mucosal pH values in healthy saliva secretors

Development of Controlled-Release Carbamide Peroxide Loaded Nanoemulgel for Tooth Bleaching: In Vitro and Ex Vivo Studies

Burst release of carbamide peroxide (CP) from traditional hydrogels causes severe inflammation to periodontal tissues. The present study explores the development of a novel CP nanoemulgel (CP-NG), an oil-in-water nanoemulsion-based gel in which CP was loaded with a view to controlling CP release. CP solid dispersions were prepared, using white soft paraffin or polyvinylpyrrolidone-white soft paraffin mixture as a carrier, prior to formulating nanoemulsions. It was found that carrier type and the ratio of CP to carrier affected drug crystallinity. Nanoemulsions formulated from the optimized CP solid dispersions were used to prepare CP-NG. It was found that the ratio of drug to carrier in CP solid dispersions affected the particle size and zeta potential of the nanoemulsions as well as drug release behavior and tooth bleaching efficacy of CP-NG. Drug release from CP-NG followed a first-order kinetic reaction and the release mechanism was an anomalous transport. Drug release rate decreased with an increase in solid dispersion carriers. CP-NG obtained from the solid dispersion with a 1:1 ratio of CP to the polymer mixture is suitable for sustaining drug release with high tooth bleaching efficacy and without reduction of enamel microhardness. The developed CP-NG is a promising potential tooth bleaching formulation.

Development and optimisation of simulated salivary fluid for biorelevant oral cavity dissolution

Drug release within the oral cavity can be of paramount importance for formulations that are designed for specific purposes such as taste-masking, faster onset of therapeutic action, localization of treatment or avoidance of first-pass metabolism. Preclinical methods for assessment of dissolution in the oral cavity are necessary for design and development of these formulation but currently there is no consensus on what variables should be defined to achieve biorelevance in these tests. In this study, biorelevant simulated salivary fluids (SSFs) that can be uniformly applied for oral cavity dissolution testing were developed. Unstimulated saliva (US) SSF and stimulated saliva (SS) SSF were separately developed since the two states significantly differ. Physicochemical properties including pH, buffer capacity, surface tension and viscosity were assessed during development and optimised to mimic human saliva (HS). In order to account for the salivary proteins in HS, use of bovine submaxillary mucin (BSM) and porcine gastric mucin (PGM) in SSFs was evaluated. Following optimisation of the SSFs, biorelevance of the developed SSFs to HS was assessed by their comparative physicochemical properties as well as dissolution profiles of three diverse model compounds (sildenafil citrate, efavirenz, and caffeine) which showed comparable profiles between the SSFs and HS. This work addresses the lack of uniformed biorelevant dissolution media for oral cavity dissolution studies and provides a basis for standardised dissolution tests that provide consistency and harmonisation in future oral cavity dissolution studies. We envisage that this will have a positive impact on the development of new medicines that require functionality in the oral cavity.

Possible proteomic biomarkers for the detection of pancreatic cancer in oral fluids

The 80% mortality rate of pancreatic-cancer (PC) makes early diagnosis a challenge. Oral fluids (OF) may be considered the ultimate body fluid for non-invasive examinations. We have developed techniques to improve visualization of minor OF proteins thereby overcoming major barriers to using OF as a diagnostic fluid. The aim of this study was to establish a short discriminative panel of OF biomarkers for the detection of PC. Unstimulated OF were collected from PC patients and controls (n = 30). High-abundance-proteins were depleted and the remaining proteins were analyzed by two-dimensional-gel-electrophoresis and quantitative dimethylation-liquid-chromatography-tandem mass-spectrometry. Label-free quantitative-mass-spectrometry analysis (qMS) was performed on 20 individual samples (n = 20). More than 100 biomarker candidates were identified in OF samples, and 21 had a highly differential expression profile. qMS analysis yielded a ROC-plot AUC value of 0.91 with 90.0% sensitivity and specificity for a combination of five biomarker candidates. We found a combination of five biomarkers for PC. Most of these proteins are known to be related to PC or other gastric cancers, but have never been detected in OF. This study demonstrates the importance of novel OF depletion methodologies for increased protein visibility and highlights the clinical applicability of OF as a diagnostic fluid.

Electrospun α-Lactalbumin Nanofibers for Site-Specific and Fast-Onset Delivery of Nicotine in the Oral Cavity: An In Vitro, Ex Vivo, and Tissue Spatial Distribution Study

Nicotine replacement therapy (NRT) formulations for oromucosal administration induce a delayed rise in nicotine blood levels as opposed to the immediate nicotine increase obtained from cigarette smoking, this being a shortcoming of the therapy. Here, we demonstrate that α-lactalbumin/polyethylene oxide (ALA/PEO) electrospun nanofibers constitute an efficient oromucosal delivery system for fast-onset nicotine delivery of high relevance for acute dosing NRT applications. In vitro, nicotine-loaded nanofibers showed fast disintegration in water, with a weight loss up to 40% within minutes, and a faster nicotine release (26.1 ± 4.6% after 1 min of incubation) of the loaded nicotine compared to two relevant marketed NRT formulations with a comparable nicotine dose (i.e., 7.9 ± 5.1 and 2.2 ± 0.3% nicotine was released from a lozenge and a sublingual tablet, respectively). Model-fitting of the release data indicated that the release mechanism of nicotine from the hydrophilic nanofibers was possibly governed by more than one type of release phenomena. Remarkably, ex vivo studies using porcine buccal mucosa demonstrated a more efficient permeation of the nicotine released from the nanofibers [flux of 1.06 ± 0.22 nmol/(cm²·min)] compared to when dosing even a ten-fold concentrated nicotine solution [flux of 0.17 ± 0.14 nmol/(cm²·min)]. Moreover, matrix-assisted laser desorption ionization mass spectrometry imaging (MALDI MS) imaging of ex vivo porcine buccal mucosa exposed to nicotine-loaded nanofibers clearly revealed higher amounts of nicotine throughout the epithelium, as well as in the lamina propria and submucosa of the tissue. Our findings suggest that nicotine-loaded ALA/PEO nanofibers have potential as a mucosal, fast-releasing, and biocompatible delivery system for nicotine, which can overcome the limitations of the currently marketed NRTs.

Delmopinol - adsorption to and absorption through the oral mucosa

OBJECTIVES

To investigate the surface chemical changes in dynamic interactions of delmopinol on salivary films on oral mucosa in healthy participants after rinsing with an unbuffered water solution of delmopinol, and to examine the oral tissue disposition of delmopinol in rats after local administration.

MATERIAL AND METHODS

The contact angle technique was used to monitor the interaction of delmopinol with the salivary film coating the upper labial mucosa of 10 healthy participants through a 4 h period. The tissue disposition of ¹⁴C-labelled delmopinol was examined in rats by autoradiography.

RESULTS

Rinsing with delmopinol increased the polarity of the saliva coated mucosa during the time of observation. The binding of delmopinol was verified in the autoradiograms showing that radioactivity remained in the rat oral mucosa after 24 h. Delmopinol was however not irreversibly bound.

CONCLUSIONS

The findings indicate that delmopinol interacts with the salivary film of the upper labial mucosa and affects its polarity. It appears that delmopinol assists in the maintenance of the hydrophilicity of the mucosal pellicle and thereby also reinforcing hydration of the mucosa. The rat autoradiograms, showed that radioactivity remains in the oral mucosa after 24 h, but diffuses through the mucosal membranes into the systemic circulation.

Preparation, characterization, and pharmacokinetics of tilmicosin taste-masked formulation via hot-melt extrusion technology

Tilmicosin (TMS) is a macrocyclic antibiotic specially used in veterinary clinics, but its extreme bitterness limits its use. This study aimed to obtain a taste-masked formulation of TMS by hot melt extrusion (HME) technology and to investigate the formulation's characterization, stability, and effects in vitro/in vivo. Eudragit® E PO was selected as the carrier, and TMS dissolution in artificial saliva was used as a reference. The HME parameters were optimized via an orthogonal design. The optimized results were as follows: 135 ℃ extrusion temperature, 100 rpm screw speed and 30 % drug load. The masking efficiency of the formulation was evaluated by both simulated oral drug release in vitro and electronic tongue tests. The release of the taste-masked formulation in artificial saliva medium was significantly reduced within 60 s (less than 2%), while the release in 0.1 M HCl buffer was fast (more than 80 %) within 30 min. As suggested by the results of the electronic tongue, the taste-masked formulation had a better taste-masked effect than the commercial premix and the commercial enteric granules. Finally, a pharmacokinetic study was performed. Analysis of variance demonstrated that the pharmacokinetic behavior of the TMS taste-masked formulation was similar to that of the commercial premix, while the absorption effect was better than that of the commercially available enteric granules. This research indicates that the taste-masked formulation has the potential for future commercialization.

Interactions of dietary polyphenols with epithelial lipids: advances from membrane and cell models in the study of polyphenol absorption, transport and delivery to the epithelium

Currently, diet-related diseases such as diabetes, obesity, hypertension, and cardiovascular diseases account for 70% of all global deaths. To counteract the rising prevalence of non-communicable diseases governments are investing in persuasive educational campaigns toward the ingestion of fresh fruits and vegetables. The intake of dietary polyphenols abundant in Mediterranean and Nordic-type diets holds great potential as nutritional strategies in the management of diet-related diseases. However, the successful implementation of healthy nutritional strategies relies on a pleasant sensory perception in the mouth able to persuade consumers to adopt polyphenol-rich diets and on a deeper understanding on the chemical modifications, that affect not only their chemical properties but also their physical interaction with epithelial lipids and in turn their permeability, location within the lipid bilayer, toxicity and biological activity, and fate during absorption at the gastro-intestinal epithelium, transport in circulation and delivery to the endothelium. In this paper, we review the current knowledge on the interactions between polyphenols and their metabolites with membrane lipids in artificial membranes and epithelial cell models (oral, stomach, gut and endothelium) and the findings from polyphenol-lipid interactions to physiological processes such as oral taste perception, gastrointestinal absorption and endothelial health. Finally, we discuss the limitations and challenges associated with the current experimental approaches in membrane and cell model studies and the potential of polyphenol-rich diets in the quest for personalized nutritional strategies ("personalized nutrition") to assist in the prevention, treatment, and management of non-communicable diseases in an increasingly aged population.

A self-healable, moldable and bioactive biomaterial gum for personalised and wearable drug delivery

One of the long-standing challenges in materials science involves synthesizing biomaterials that recapitulate important features of native biological tissues. Even though, the number of available biomaterials at the moment are virtually limitless, few of them has unlocked all the secrets of the human body by mimicking the combinatorial-like material properties of our tissues and organs. Inspired by the human body, we have developed a polymeric gum, which combines stretchability, toughness, strength, flexibility, and self-healing. It also exhibits a high bioactivity that can target and eliminate bacterial infections fast and reliably. Notably, this material is moldable into almost any complex shape, and therefore suitable as a building block for wearables designed to conform directly with the curved and personalized anatomy of patients. It also exhibits excellent drug retention and release capacity, which altogether makes it suitable for applications in personalized wearable drug-delivery devices.

Advances in Understanding the Human Urinary Microbiome and Its Potential Role in Urinary Tract Infection

Recent advances in the analysis of microbial communities colonizing the human body have identified a resident microbial community in the human urinary tract (UT). Compared to many other microbial niches, the human UT harbors a relatively low biomass. Studies have identified many genera and species that may constitute a core urinary microbiome. However, the contribution of the UT microbiome to urinary tract infection (UTI) and recurrent UTI (rUTI) pathobiology is not yet clearly understood. Evidence suggests that commensal species within the UT and urogenital tract (UGT) microbiomes, such as Lactobacillus crispatus, may act to protect against colonization with uropathogens. However, the mechanisms and fundamental biology of the urinary microbiome-host relationship are not understood. The ability to measure and characterize the urinary microbiome has been enabled through the development of next-generation sequencing and bioinformatic platforms that allow for the unbiased detection of resident microbial DNA. Translating technological advances into clinical insight will require further study of the microbial and genomic ecology of the urinary microbiome in both health and disease. Future diagnostic, prognostic, and therapeutic options for the management of UTI may soon incorporate efforts to measure, restore, and/or preserve the native, healthy ecology of the urinary microbiomes.

Mucoadhesive Budesonide Formulation for the Treatment of Eosinophilic Esophagitis

Eosinophilic esophagitis (EE) is a chronic immune/antigen-mediated esophageal inflammatory disease for which off-label topical corticosteroids (e.g., budesonide) are widely used in clinic. In general, thickening excipients are mixed with industrial products to improve the residence time of the drug on the esophageal mucosa. The compounding procedures are empirical and the composition is not supported by real physicochemical and technological characterization. The current study aimed to propose a standardized budesonide oral formulation intended to improve the resistance time of the drug on the esophageal mucosa for EE treatment. Different placebo and drug-loaded (0.025% w/w) formulations were prepared by changing the percentage of xanthan gum alone or in ratio 1:1 with guar gum. Both excipients were added in the composition for their mucoadhesive properties. The formulative space was rationalized based on the drug physicochemical stability and the main critical quality attributes of the formulation, e.g., rheological properties, syringeability, mucoadhesiveness and in vitro penetration of budesonide in porcine esophageal tissue. The obtained results demonstrated that gums allowed a prolonged residence time. However, the concentration of the mucoadhesive polymer has to be rationalized appropriately to permit the syringeability of the formulation and, therefore, easy dosing by the patient/caregiver.

Hemagglutinin Stability Regulates H1N1 Influenza Virus Replication and Pathogenicity in Mice by Modulating Type I Interferon Responses in Dendritic Cells

Hemagglutinin (HA) stability, or the pH at which HA is activated to cause membrane fusion, has been associated with the replication, pathogenicity, transmissibility, and interspecies adaptation of influenza A viruses. Here, we investigated the mechanisms by which a destabilizing HA mutation, Y17H (activation pH, 6.0), attenuates virus replication and pathogenicity in DBA/2 mice compared to wild-type (WT) virus (activation pH, 5.5). The extracellular lung pH was measured to be near neutral (pH 6.9 to 7.5). WT and Y17H viruses had similar environmental stability at pH 7.0; thus, extracellular inactivation was unlikely to attenuate the Y17H virus. The Y17H virus had accelerated replication kinetics in MDCK, A549, and RAW 264.7 cells when inoculated at a multiplicity of infection (MOI) of 3 PFU/cell. The destabilizing mutation also increased early infectivity and type I interferon (IFN) responses in mouse bone marrow-derived dendritic cells (DCs). In contrast, the HA-Y17H mutation reduced virus replication in murine airway murine nasal epithelial cell and murine tracheal epithelial cell cultures and attenuated virus replication, virus spread, the severity of infection, and cellular infiltration in the lungs of mice. Normalizing virus infection and weight loss in mice by inoculating them with Y17H virus at a dose 500-fold higher than that of WT virus revealed that the destabilized mutant virus triggered the upregulation of more host genes and increased type I IFN responses and cytokine expression in DBA/2 mouse lungs. Overall, HA destabilization decreased virulence in mice by boosting early infection in DCs, resulting in the greater activation of antiviral responses, including the type I IFN response. These studies reveal that HA stability may regulate pathogenicity by modulating IFN responses.IMPORTANCE Diverse influenza A viruses circulate in wild aquatic birds, occasionally infecting farm animals. Rarely, an avian- or swine-origin influenza virus adapts to humans and starts a pandemic. Seasonal and many universal influenza vaccines target the HA surface protein, which is a key component of pandemic influenza viruses. Understanding the HA properties needed for replication and pathogenicity in mammals may guide response efforts to control influenza. Some antiviral drugs and broadly reactive influenza vaccines that target the HA protein have suffered resistance due to destabilizing HA mutations that do not compromise replicative fitness in cell culture. Here, we show that despite not compromising fitness in standard cell cultures, a destabilizing H1N1 HA stalk mutation greatly diminishes viral replication and pathogenicity in vivo by modulating type I IFN responses. This encourages targeting the HA stalk with antiviral drugs and vaccines as well as reevaluating previous candidates that were susceptible to destabilizing resistance mutations.

Mucoadhesive buccal film of almotriptan improved therapeutic delivery in rabbit model

Administration of almotriptan as an oral therapy is largely limited because of poor aqueous solubility and rather low bioavailability. The aim of present investigation was to formulate oral mucoadhesive film of almotriptan to improve the drug delivery and desired therapeutic effects. Placebo films (F1-F8) were prepared by varying the concentrations of Proloc 15 (7.5-15% w/v) and Eudragit RL 100/RS 100 (15-30% w/v) polymers. Physicomechanical and pharmaceutical characteristics of drug loaded films (FA1-FA4) were examined. Selected FA4 film was evaluated in vivo by assessing the pharmacokinetic profile and compared with oral therapy in rabbits. FA1-FA4 films exhibited excellent physicomechanical properties and rapid hydration. A biphasic and considerably greater drug release (p < 0.05) was observed in FA3 and FA4 films contain higher amount of hydrophilic polymer. The rate of permeation of almotriptan was found to be significantly higher in FA4 than FA3 film (p < 0.005). Fourier transform infrared spectral scan indicates no incompatibility exists between the drug and polymers used. Differential scanning calorimetry thermogram represents the evidence of almotriptan amorphization and molecular dispersion of it in the film. Scanning electron microscopy images shows that FA4 possess good morphological features and hence suitable for use in the buccal application. In vivo data demonstrated rapid and efficient absorption (p < 0.005) of almotriptan with greater AUC_0-12 (>2 folds, p < 0.0001) by FA4 film as compared to oral (control). In general, the data established the potential of FA4 film to improve the therapeutic delivery of almotriptan and offers a promising option in migraine therapy.

3D printing of multilayered orodispersible films with in-process drying

The aim of this study was to prepare benzydamine hydrochloride loaded orodispersible films using modified semisolid extrusion 3D printing method. An innovative approach was developed where thin layer of drug loaded dispersion is printed and dried before printing of subsequent layers. Layer-by-layer drying as the in process step improves mechanical properties of films, uniformity of drug content and allows faster preparation of films in compounding settings due to shortening of drying time. Orodispersible films consisted of film forming maltodextrin, sorbitol as a plasticizer and hydroxyethylcellulose as a thickening agent. The height of the digital model showed excellent correlation with the disintegration time, weight, thickness and mechanical properties of prepared films. Drug content, predefined by volume of digital model and concentration of drug in print dispersion, showed excellent uniformity. The modified printing method shows great promise in a compounding production of personalized film dosage forms, and brings in possibilities such as one step preparation of films with compartmented drugs and incorporation of taste masking or release control layers.

Nanoparticles And Human Saliva: A Step Towards Drug Delivery Systems For Dental And Craniofacial Biomaterials

Aim

The aims of this study were to investigate new nano-formulations based on ZnO and Ag nanoparticle (NP) compounds when used against clinical strains of oral gram-positive and gram-negative bacteria, and to examine the stability and behaviour of nano-formulation mixtures in saliva based on different compositions of Ag NPs, ZnO NPs and ZnO+x·Ag NPs. Methods: ZnO NPs with and without nanosilver were obtained by microwave solvothermal synthesis. Then, antibacterial activity was evaluated against bacteria isolated from human saliva. Behavior and nanoparticle solutions were evaluated in human saliva and control (artificial saliva and deionized water). Results were statistically compared.

Results

The NP mixtures had an average size of 30±3 nm, while the commercial Ag NPs had an average size of 55±5 nm. The suspensions displayed differing antibacterial activities and kinetics of destabilisation processes, depending on NPs composition and fluid types.

Conclusion

The present study showed that all NPs suspensions displayed significant destabilisation and high destabilisation over the 24 h of the analyses. The agglomeration processes of NPs in human saliva can be reversible.

Human saliva and model saliva at bulk to adsorbed phases - similarities and differences

Human saliva, a seemingly simple aqueous fluid, is, in fact, an extraordinarily complex biocolloid that is not fully understood, despite many decades of study. Salivary lubrication is widely believed to be a signature of good oral health and is also crucial for speech, food oral processing and swallowing. However, saliva has been often neglected in food colloid research, primarily due to its high intra- to inter-individual variability and altering material properties upon collection and storage, when used as an ex vivo research material. In the last few decades, colloid scientists have attempted designing model (i.e. 'saliva mimicking fluid') salivary formulations to understand saliva-food colloid interactions in an in vitro set up and its contribution on microstructural aspects, lubrication properties and sensory perception. In this Review, we critically examine the current state of knowledge on bulk and interfacial properties of model saliva in comparison to real human saliva and highlight how far such model salivary formulations can match the properties of real human saliva. Many, if not most, of these model saliva formulations share similarities with real human saliva in terms of biochemical compositions, including electrolytes, pH and concentrations of salivary proteins, such as α-amylase and highly glycosylated mucins. This, together with similarities between model and real saliva in terms of surface charge, has led to significant advancement in decoding various colloidal interactions (bridging, depletion) of charged emulsion droplets and associated sensory perception in the oral phase. However, model saliva represents significant dissimilarity to real saliva in terms of lubricating properties. Based on in-depth examination of properties of mucins derived from animal sources (e.g. pig gastric mucins (PGM) or bovine submaxillary mucin (BSM)), we can recommend that BSM is currently the most optimal commercially available mucin source when attempting to replicate saliva based on surface adsorption and lubrication properties. Even though purification via dialysis or chromatographic techniques may influence various physicochemical properties of BSM, such as structure and surface adsorption, the lubricating properties of model saliva formulations based on BSM are generally superior and more reliable than the PGM counterpart at orally relevant pH. Comparison of mucin-containing model saliva with ex vivo human salivary conditioning films suggests that mucin alone cannot replicate the lubricity of real human salivary pellicle. Mucin-based multi-layers containing mucin and oppositely charged polyelectrolytes may offer promising avenues in the future for engineering biomimetic salivary pellicle, however, this has not been explored in oral tribology experiments to date. Hence, there is a strong need for systematic studies with employment of model saliva formulations containing mucins with and without polycationic additives before a consensus on a standardized model salivary formulation can be achieved. Overall, this review provides the first comprehensive framework on simulating saliva for a particular bulk or surface property when doing food oral processing experiments.

Proteomic profiling of whole-saliva reveals correlation between Burning Mouth Syndrome and the neurotrophin signaling pathway

Burning mouth syndrome (BMS) is characterized by a spontaneous and chronic sensation of burning in the oral mucosa, with no apparent signs. The underlying pathophysiological and neuropathic mechanisms remain unclear. Here, we attempt to elucidate some of these mechanisms using proteomic profiling and bioinformatic analyses of whole-saliva (WS) from BMS patients compared to WS from healthy individuals. Qualitative and quantitative proteomic profiling was performed using two dimensional gel electrophoresis (2-DE) and quantitative mass spectrometry (q-MS). In order to improve protein visibility, 21 high abundance proteins were depleted before proteomic profiling. Quantitative proteomic analysis revealed 100 BMS specific proteins and an additional 158 proteins up-regulated by more than threefold in those with BMS. Bioinformatic analyses of the altered protein expression profile of BMS group indicated high correlations to three cellular mechanisms including the neurotrophin signaling pathway. Based on this finding, we suggest that neurotrophin signaling pathway is involved in the pathophysiology of BMS by amplifying P75NTR activity, which in turn increases neural apoptosis thereby reducing sub-papillary nerve fiber density in the oral mucosa.

A new strategy for taste masking of azithromycin antibiotic: development, characterization, and evaluation of azithromycin titanium nanohybrid for masking of bitter taste using physisorption and panel testing studies

Background

The obnoxious bitter taste of orally taken antibiotics is one of the biggest problems in the treatment of children. The pediatric population cannot tolerate the bitter taste of drugs and vomit out which ultimately leads to suboptimal therapeutic value, grimace and mental stress so it is the challenging task for the formulation scientists to formulate a palatable formulation particularly to overcome address the issue.

Purpose of study

The study aimed to mask and evaluate the unpleasant bitter taste of azithro-mycin (AZ) in the dry suspension dosage form by physisorption technique.

Materials and methods

AZ was selected as an adsorbent and titanium dioxide nanoparticles as adsorbate. The AZ nanohybrids (AZN) were prepared by treating fixed amount of adsorbent with a varied amount of adsorbate, prepared separately by dispersing it in an aqueous medium. The mixture was sonicated, stirred followed by filtration and drying. The AZN produced were characterized by various techniques including scanning electron microscopy (SEM), energy dispersive X-rays (EDX), powder X-ray diffraction (PXRD), HPLC and Fourier-transformed infrared (FTIR). The optimized nanohybrid was blended with other excipients to get stable and taste masked dry suspension dosage form.

Results

The results confirmed the adsorption of titanium dioxide nanoparticles on the surface of AZ. The fabricated optimized formulation was subjected for taste masking by panel testing and accelerated stability studies. The results showed a remarkable improvement in bitter taste masking, inhibiting throat bite without affecting the dissolution rate. The product showed an excellent stability both in dry and reconstituted suspension. The optimized formulation of AZN and was found stable when subjected to physical and chemical stability studies, this is because of short and single step process which interns limits the exposure of the product to various environmental factors that could potentially affect the stability of the product. The dissolution rate of the optimized formulation of AZN was compared with its marketed counterpart, showing the same dissolution rate compared to its marketed formulation.

Conclusion

The current study concludes that, by fabricating AZ-titanium nanohybrids using physisorption can effectively mask the bitter taste of the drug. The palatability and stability of azithromycin formulation was potentially enhanced without affecting its dissolution rate.

Influenza Hemagglutinin Protein Stability, Activation, and Pandemic Risk

For decades, hemagglutinin (HA) protein structure and its refolding mechanism have served as a paradigm for understanding protein-mediated membrane fusion. HA trimers are in a high-energy state and are functionally activated by low pH. Over the past decade, HA stability (or the pH at which irreversible conformational changes are triggered) has emerged as an important determinant in influenza virus host range, infectivity, transmissibility, and human pandemic potential. Here, we review HA protein structure, assays to measure its stability, measured HA stability values, residues and mutations that regulate its stability, the effect of HA stability on interspecies adaptation and transmissibility, and mechanistic insights into this process. Most importantly, HA stabilization appears to be necessary for adapting emerging influenza viruses to humans.

Green Tea Polyphenol Epigallocatechin-3-Gallate-Stearate Inhibits the Growth of Streptococcus mutans: A Promising New Approach in Caries Prevention

Streptococcus mutans (S. mutans) is the main etiological bacteria present in the oral cavity that leads to dental caries. All of the S. mutans in the oral cavity form biofilms that adhere to the surfaces of teeth. Dental caries are infections facilitated by the development of biofilm. An esterified derivative of epigallocatechin-3-gallate (EGCG), epigallocatechin-3-gallate-stearate (EGCG-S), was used in this study to assess its ability to inhibit the growth and biofilm formation of S. mutans. The effect of EGCG-S on bacterial growth was evaluated with colony forming units (CFU) and log reduction; biofilm formation was qualitatively determined by Congo red assay, and quantitatively determined by crystal violet assay, fluorescence-based LIVE/DEAD assays to study the cell viability, and scanning electron microscopy (SEM) was used to evaluate the morphological changes. The results indicated that EGCG-S was able to completely inhibit growth and biofilm formation at concentrations of 250 µg/mL. Its effectiveness was also compared with a commonly prescribed mouthwash in the United States, chlorhexidine gluconate. EGCG-S was shown to be equally effective in reducing S. mutans growth as chlorhexidine gluconate. In conclusion, EGCG-S is potentially an anticariogenic agent by reducing bacterial presence in the oral cavity.

Development of Orodispersible Films Containing Benzydamine Hydrochloride Using a Modified Solvent Casting Method

The aim of this study was to develop benzydamine hydrochloride-loaded orodispersible films using the modification of a solvent casting method. An innovative approach was developed when the drying process of a small-scale production was used based on a heated inert base for casting the film. During this process, two types of film-forming maltodextrins for rapid drug delivery were used. They were plasticized with two different polyols (xylitol and sorbitol). Superdisintegrant Kollidon® CL-F was tested as an excipient that can induce faster disintegration of the prepared films. The influence of the formulation parameters (dextrose equivalent of film-forming maltodextrins, a type of plasticizer, and the presence of superdisintegrant) on the disintegration time, mechanical properties, and moisture content of films was statistically evaluated using a multivariate data analysis. Orodispersible films containing maltodextrin with lower dextrose equivalent value showed better mechanical properties (tensile strength ranged from 886.6 ± 30.2 to 1484.2 ± 226.9 N cm^-2), lower moisture content (0.5 ± 0.0 to 1.2 ± 0.2%), and shorter disintegration time (17.6 ± 2.9 to 27.8 ± 2.8 s). Films plasticized with xylitol showed shorter disintegration time (17.6 ± 2.9 to 29.2 ± 3.8 s) than films containing sorbitol (23.8 ± 2.9 to 31.7 ± 3.9 s). With the addition of superdisintegrant Kollidon® CL-F, a significant influence on disintegration time was not observed. The modified solvent casting method shows great promise in a small-scale laboratory production of orodispersible films, e.g., in a pharmacy lab.

Akkermansia muciniphila in the Human Gastrointestinal Tract: When, Where, and How?

Akkermansia muciniphila is a mucin-degrading bacterium of the phylum Verrucomicrobia. Its abundance in the human intestinal tract is inversely correlated to several disease states. A. muciniphila resides in the mucus layer of the large intestine, where it is involved in maintaining intestinal integrity. We explore the presence of Akkermansia-like spp. based on its 16S rRNA sequence and metagenomic signatures in the human body so as to understand its colonization pattern in time and space. A. muciniphila signatures were detected in colonic samples as early as a few weeks after birth and likely could be maintained throughout life. The sites where Akkermansia-like sequences (including Verrucomicrobia phylum and/or Akkermansia spp. sequences found in the literature) were detected apart from the colon included human milk, the oral cavity, the pancreas, the biliary system, the small intestine, and the appendix. The function of Akkermansia-like spp. in these sites may differ from that in the mucosal layer of the colon. A. muciniphila present in the appendix or in human milk could play a role in the re-colonization of the colon or breast-fed infants, respectively. In conclusion, even though A. muciniphila is most abundantly present in the colon, the presence of Akkermansia-like spp. along the digestive tract indicates that this bacterium might have more functions than those currently known.

Effect of fixed orthodontic appliances on nonmicrobial salivary parameters

OBJECTIVES:

To examine possible changes in the levels of salivary antioxidants, C-reactive protein (CRP), cortisol, pH, proteins, and blood in patients treated with fixed orthodontic appliances.

MATERIALS AND METHODS:

Salivary samples from 21 orthodontic patients who met specific inclusion criteria were collected before the beginning of orthodontic treatment (T0; baseline), 1 hour after bonding (T1), and 4-6 weeks after bonding (T2). Oxidant-scavenging ability (OSA) was quantified using a luminol-dependent chemiluminescence assay. Cortisol and CRP levels were measured using immunoassay kits. pH levels and presence of proteins and blood in the samples were quantified using strip-based tests.

RESULTS:

A significant decrease in salivary pH was observed after bonding ( P = .013). An increase in oxidant-scavenging abilities during orthodontic treatment was detected, but the change was not statistically significant. Cortisol and CRP levels slightly increased after bonding, but the difference was small without statistical significance. Changes in the presence of proteins and blood were also insignificant.

CONCLUSIONS:

Exposure to fixed orthodontic appliances did not show a significant effect on salivary parameters related to inflammation or stress, with the exception of a significant but transient pH decrease after bonding.

Identification of Candida albicans regulatory genes governing mucosal infection

The fungus Candida albicans thrives on a variety of human mucosae, yet the fungal determinants that contribute to fitness on these surfaces remain underexplored. Here, by screening a collection of C. albicans deletion strains in a mouse model of oral infection (oropharyngeal candidiasis), we identify several novel regulatory genes that modulate the fitness of the fungus in this locale. We investigate in detail the interplay between the host mucosa and one of the identified mutants and establish that the C. albicans transcription regulator CUP9 is a key determinant of mucosal colonisation. Deletion of cup9 resulted in the formation of more foci of colonisation and heightened persistence in infected tongues. Furthermore, the cup9 mutant produced longer and denser filaments in the oral mucosa without eliciting an enhanced local immune response. Consistent with its role in oral colonisation, we show that CUP9's top target of regulation is a major effector of Candida's adherence to buccal cells. Finally, we establish that CUP9 also governs the interplay of the fungus with vaginal epithelial cells and has a role in vaginal infections, another common mucosal disease associated with Candida. Thus, our findings reveal a mechanism whereby C. albicans can regulate proliferation on mucosal surfaces.

Comparison of the effect of pharmacotherapy and neuro-feedback therapy on oral health of children with attention deficit hyperactivity disorder

Background

Attention deficit hyperactivity disorder (ADHD) is a chronic and progressive mental disorder related to the childhood period. This study aims to compare the oral health of two groups of ADHD children: those under pharmacotherapy and those under neuro-feedback therapy.

Material and Methods

72 ADHD children (aged 6-12) were divided into two 36 member groups: The pharmacotherapy group and the neuro-feedback therapy group. Unstimulated salivary flow (USF), DMFT, and plaque index were assessed in these children. Statistical analysis was carried out on the data with the independent t-test, which was performed using SPSS 16. The significance level of the study was p<0.05.

Results

In this study, the USF of ADHD children who used Ritalin was found to be significantly less than that of the neuro-feedback group (1.25 ± 1.21 vs. 1.91 ± 1.16 ml/min; p=0.002). Also, the plaque index (5.9 ± 3.1 vs. 3.94 ± 1.9; p=0.018) and DMFT scores (39% ± 9% vs. 31% ± 9%; p=0.018) were significantly higher for the pharmacotherapy group.

Conclusions

Neuro-feedback therapy is preferable to Ritalin treatment for ADHD children in terms of their oral health status. Key words:Attention deficit hyperactivity disorder, drug therapy, neurofeedback, oral health.

A theoretical physiologically based pharmacokinetic approach for modeling the fate of anthocyanins in vivo

Recent studies on the pharmacokinetics of anthocyanins (ACNs) and their metabolites have uncovered evidence for hitherto unknown physiological effects affecting the fate of these compounds in vivo. In particular, it has been shown that the stomach, in addition to the small intestine, has an important role in absorption. Most studies still use a noncompartmental or one-compartmental approach to determine the pharmacokinetic parameters of ACNs, which does not represent the anatomical and physiological conditions that a compound is subject to in the organism. Thus, the objective of this study was to review the current knowledge of the different processes involved in the metabolism of ACNs once ingested and, based on this information, propose a theoretical physiologically based, multicompartmental pharmacokinetic (PBMK) model to describe their fate in vivo. This is the first study that reports a PBMK model for ACNs; the model provides a more physiologically representative approach for ANC metabolism, which could be used as a basis for experimental designs and interspecies scale-up.

Characterization, mechanistic analysis and improving the properties of denture adhesives

OBJECTIVE

Denture adhesives are widely used to avoid the detachment and sliding of dentures. However, the adhesion properties can be affected by variation in mouth conditions such as the level of salivation. The objective of this study was to understand the effect of environmental conditions on the adhesion properties of a commercially available denture adhesive named as Poligrip^® Free manufactured by GlaxoSmithKline Ltd., UK and to identify the reasons for the observed variation in its adhesion strength.

METHODS

The failure mechanisms of denture adhesive have been assessed through using different physical, mechanical and thermal characterization experiments. All methods were used in different pH, temperatures, and salivation conditions and at the end, a strategy was proposed to overcome the failure of the paste in hyposalivation as well.

RESULTS

In vitro models mimicking the denture gingival interface were designed to evaluate the adhesion properties of the investigated adhesive. Changes in the adhesion strength in response to three major factors related to the oral conditions including level of salivation, pH, and temperature were measured. The results of lap shear, tensile test, and internal interactions suggested a cohesion failure, where the lowest adhesion strength was due to hyposalivation. Fourier transform infrared spectroscopy (FTIR) and rheological analysis confirmed the importance of hydrogen bonds and hydration in the adhesion strength of the paste.

SIGNIFICANCE

The investigated scenarios are widely observed in patient using denture adhesives and the clinical reports have indicated the inconsistency in adhesion strength of the commercial products. After identifying the potential reasons for such behavior, methods such as the addition of tripropylene glycol methyl ether (TPME) to enhance internal hydrogen bonds between the polymers are proposed to improve adhesion in the hyposalivation scenario.

Syndromic deafness mutations at Asn 14 differentially alter the open stability of Cx26 hemichannels

Connexin 26 (Cx26) is a transmembrane protein that forms hexameric hemichannels that can function when unopposed or dock to form intercellular gap junction channels. Aberrantly functioning unopposed hemichannels are a common feature of syndromic deafness associated with mutations in Cx26. In this study, we examine two different mutations at the same position in the N-terminal domain of Cx26, N14K and N14Y, which have been reported to produce different phenotypes in patients. We find that both N14K and N14Y, when expressed alone or together with wild-type (WT) Cx26, result in functional hemichannels with widely disparate functional properties. N14K currents are robust, whereas N14Y currents are small. The two mutants also exhibit opposite shifts in voltage-dependent loop gating, such that activation of N14K and N14Y is shifted in the hyperpolarizing and depolarizing directions, respectively. Deactivation kinetics suggests that N14K stabilizes and N14Y destabilizes the open state. Single N14K hemichannel recordings in low extracellular Ca(2+) show no evidence of stable closing transitions associated with loop gating, and N14K hemichannels are insensitive to pH. Together, these properties cause N14K hemichannels to be particularly refractory to closing. Although we find that the unitary conductance of N14K is indistinguishable from WT Cx26, mutagenesis and substituted cysteine accessibility studies suggest that the N14 residue is exposed to the pore and that the differential properties of N14K and N14Y hemichannels likely result from altered electrostatic interactions between the N terminus and the cytoplasmic extension of TM2 in the adjacent subunit. The combined effects that we observe on loop gating and pH regulation may explain the unusual buccal cutaneous manifestations in patients carrying the N14K mutation. Our work also provides new considerations regarding the underlying molecular mechanism of loop gating, which controls hemichannel opening in the plasma membrane.

New formulation and approach for mucoadhesive buccal film of rizatriptan benzoate

Mucoadhesive buccal film is developed as a promising dosage form, which has prominent advantages because of drug delivery through buccal mucosa. New formulation of buccal films containing rizatriptan benzoate (RB) was prepared by solvent casting method using various concentrations of hydroxypropyl methylcellulose (HPMC K4M), polyvinyl alcohol (PVA), polyethylene oxide (PEO), glycerol, stevia, and goat buccal mucosa used as a model membrane. In this work, the effect of polymers and plasticizer concentrations on drug release profile, disintegration and dissolution time, mechanical properties, and mucoadhesive characteristics of films was studied. Scanning electron microscopy analysis revealed uniform distribution of RB in film formulations. Chemical compounds and thermal analysis of the films were studied by Fourier transform infrared spectroscopy and differential scanning calorimetry, respectively. The buccal films produced were uniform in drug content and thickness. All formulations have in vitro release of 98–102% between 40 and 80 min. Also ex vivo mucoadhesion strength was in the range of 0.205 ± 0.035 to 0.790 ± 0.014 N for all formulations. A formulation consisting RB (50 mg), HPMC K4M, PVA, and PEO (63 mg), glycerol (1.5 ml), stevia (5 mg) was selected as our optimum composition. More satisfactory results were obtained in terms of disintegration and dissolution time, mechanical properties, and mucoadhesive characteristics. In addition, it showed about 99.89% RB released in 45 min. The results suggest that RB-loaded mucoadhesive buccal films could be a potential candidate to achieve optimum drug release for effective treatment of migraine.

Horseradish and radish peroxidases eaten with fish could help explain observed associations between fish consumption and protection from age-related dementia

A juxtaposition of regional cuisines and recent prospective studies of fish consumption in China and Japan points to fresh horseradish and/or radish (HRR) as possible contributors to delaying age-related dementia. The hypothesis is that the inverse association found sometimes between fish intake and cognitive decline is partially due to exposure of the oral cavity to active peroxidases from HRR served in conjunction with fish. This hypothesis can be tested by specifically looking at whether HRR is consumed with fish and whether such HRR is prepared in a way that preserves activity of HRR peroxidases. It is possible that by putting active HRR peroxidases in their mouths, elderly people supplement their age-diminished salivary antioxidant capacity and break down additional hydrogen peroxide (H₂O₂) in the oral cavity before it can migrate into the brain, thus decreasing the incidence of brain cell death induction by chronically-elevated H₂O₂. Intentional exposure of the oral cavity to active HRR peroxidases could be a prophylactic for delaying dementia. Because vegetable peroxidases are inactivated by gastric juices, it will be difficult to obtain benefit from HRR peroxidases' antioxidant effect via ingestion in encapsulated dietary supplements.

Mucoadhesive buccal tablets containing silymarin Eudragit-loaded nanoparticles: formulation, characterisation and ex vivo permeation

Eudragit-loaded silymarin nanoparticles (SNPs) and their formulation into buccal mucoadhesive tablets were investigated to improve the low bioavailability of silymarin through buccal delivery. Characterisation of SNPs and silymarin buccal tablets (SBTs) containing the optimised NPs were performed. Ex vivo permeability of nominated SBTs were assessed using chicken pouch mucosa compared to SNPs and drug suspension followed by histopathological examination. Selected SNPs had a small size (<150 nm), encapsulation effciency (>77%) with drug release of about 90% after 6 h. For STBs, all physicochemical parameters were satisfactory for different polymers used. DSC and FT-IR studies suggested the presence of silymarin in an amorphous state. Ex vivo permeation significantly emphasised the great enhancement of silymarin permeation after NPs formation and much more increase after formulating into BTs relative to the corresponding drug dispersion with confirmed membrane integrity. Incorporation of SNPs into BTs could be an efficient vehicle for delivery of silymarin.

Solid state characterisation and taste masking efficiency evaluation of polymer based extrudates of isoniazid for paediatric administration

Hot melt extrusion has gained considerable attention as a novel technique for taste masking of bitter APIs. The aim of this study was to investigate whether hot melt extrusion could be used to develop taste masked formulations of isoniazid and also to evaluate and correlate different taste assessment methods Two polymers with different physico-chemical properties, Soluplus and Eudragit E-PO were chosen as carriers for the drug. Eudragit E-PO has already been widely used for taste masking due to its selective release properties, while Soluplus has not been studied in this regard but provides a useful comparator of a polymer that should release the drug reasonably efficiently. Polymeric formulations of isoniazid were produced with drug loadings of 20% and 30% w/w. The solid state characteristics of the formulations were assessed by differential scanning calorimetry and powder X-ray diffraction. The taste of isoniazid was assessed using the rodent Brief Access Taste Aversion (BATA) model, while formulations were assessed using the electronic tongue and dissolution under simulated oral conditions. Investigation into the drug loading effect with these two polymers showed that all Soluplus based extrudates with drug loading up to 30% w/w were fully amorphous while Eudragit E-PO based extrudates contained crystalline drug as demonstrated by both DSC and PXRD, dependent on loading. BATA testing of isoniazid gave an IC₅₀ value, i.e. the dose of drug which inhibits 50% of licks, of 11.1mg/mL. Taste assessment of the formulations using both simulated oral drug release and the electronic tongue demonstrated that Eudragit E-PO based formulations had a better taste masking efficiency than Soluplus. This is due to the fact that significantly less isoniazid is released from the Eudragit E-PO based formulations under oral conditions.

Diurnal variation of intraoral pH and temperature

Objective/Aims

The aim of this study was to measure continuously the intraoral pH and temperature of healthy individuals to investigate their diurnal variations.

Materials and Methods

Seventeen participants (mean age, 31±9 years) wore a custom-made intraoral appliance fitted with a pH probe and thermocouple for two sets of 24 h, while carrying out normal daily activities including sleep. The continuous changes in intraoral pH and temperature were captured using a sensor placed on the palatal aspect of the upper central incisors. The collected data were categorised into different status (awake and sleep) and periods (morning, afternoon, evening and night). Both quantitative and qualitative analyses were conducted.

Results

The intraoral pH change was found to show a distinctive daily rhythm, showing a 12-h interval between maximum (7.73) and minimum (6.6) pH values. The maximum and minimum values were found to repeat after 24 h. The mean pH over 48 h (two sets of 24 h) was found to be 7.27 (±0.74). There was significant difference found in pH when subjects were awake and asleep and different periods during the day (P<0.001). The mean intraoral temperature was 33.99 °C (±4.9), with less distinctive daily rhythm compared with pH. There was a significant difference found in temperature depending on the time of the day, except between morning and afternoon (P=0.78).

Conclusion

Our results showed that there is a distinctive daily, circadian-like pattern in intraoral pH variation over a 24-h period, which has been considered as one of the risk factors in sleep-related dental diseases.

Preparation, characterization, and evaluation of amphotericin B-loaded MPEG-PCL-g-PEI micelles for local treatment of oral Candida albicans

Fatal Candida albicans infections in the mucosal system can occur in association with immune-compromised diseases and dysbacteriosis. Currently, amphotericin B (AmB) is considered to be the most effective antibiotic in the treatment of C. albicans infections, but its clinical application is limited by side effects and poor bioavailability. In order to use AmB in the local treatment of oral C. albicans infections, AmB/MPEG-PCL-g-PEI (monomethoxy poly(ethylene glycol)-poly(epsilon-caprolactone)-graft-polyethylenimine, MPP) micelles were prepared. A series of characterizations were performed. The micelles allowed a sustained in vitro release in both normal oral conditions (pH 6.8) and C. albicans infection conditions (pH 5.8). Then, buccal tablets containing freeze-dried powder of AmB/MPP micelles were produced by direct compression process and evaluated as regards to weight variation, hardness, and friability. In vitro drug release of the buccal tablets was measured in both the United States Pharmacopeia dissolution apparatus and the dissolution rate test apparatus, which was previously designed for simulating in vivo conditions of the oral cavity. The buccal tablets could sustainably release within 8 h and meet the antifungal requirements. Regarding safety assessment of AmB/MPP micelles, in vivo histopathological data showed no irritation toward buccal mucosa of the rats in both optical microscopy and ultrastructure observation of the tissues. MTT experiment proved that AmB/MPP micelles reduced the cytotoxicity of AmB. The micelles delivered through the gastrointestinal route were also found to be non-systemic toxicity by liquid chromatography-mass spectrometry analysis. Furthermore, the antifungal action of AmB/MPP micelles was evaluated. Although AmB/MPP had no obvious improvement as compared to AmB alone in the antifungal effect on planktonic C. albicans, the micelles significantly enhanced the antifungal activity against the biofilm state of C. albicans. Thus, it was concluded that AmB/MPP micelles represent a promising novel drug delivery system for the local treatment of oral C. albicans infections.

Vitamin B12-Loaded Buccoadhesive Films as a Noninvasive Supplement in Vitamin B12 Deficiency: In Vitro Evaluation and In Vivo Comparative Study With Intramuscular Injection

This study aimed to formulate and evaluate vitamin B12-loaded buccal mucoadhesive hydrogel films. Various film formulations were prepared using chitosan and polyvinyl alcohol. The prepared films were characterized for thickness, weight variation, drug content, percentage moisture uptake and moisture content, surface pH, mechanical properties, in vitro release, and mucoadhesion. Vitamin B12 bioavailability from the optimized formulation was studied on rabbits by the aid of enzyme-linked immunosorbent assay. Neuroton^® I.M. injection was used for comparison. The films had acceptable mechanical and mucoadhesion properties. The percentages of moisture content of the optimized formulation were 3.2 ± 0.95, whereas the percentage drug released was 98.59 ± 1.41% at the end of 40 min. FTIR revealed the incidence of drug/polymer interaction. Differential scanning calorimetry revealed the possibility of the dispersion of cyanocobalamin in a molecular state with complete amorphization in the polymers. The estimated AUC_0-8h showed 1.5-fold increases in the bioavailability of cyanocobalamin from the optimized formulation compared with the marketed I.M. injection. These findings warrant that vitamin B12 buccal film formulation can be considered as an effective alternative portal with noninvasive and more convenient characteristics compared with the I.M. injection dosage form.

A Novel Biomimetic Approach to Repair Enamel Cracks/Carious Damages and to Reseal Dentinal Tubules by Amorphous Polyphosphate

Based on natural principles, we developed a novel toothpaste, containing morphogenetically active amorphous calcium polyphosphate (polyP) microparticles which are enriched with retinyl acetate ("a-polyP/RA-MP"). The spherical microparticles (average size, 550 ± 120 nm), prepared by co-precipitating soluble Na-polyP with calcium chloride and supplemented with retinyl acetate, were incorporated into a base toothpaste at a final concentration of 1% or 10%. The "a-polyP/RA-MP" ingredient significantly enhanced the stimulatory effect of the toothpaste on the growth of human mesenchymal stem cells (MSC). This increase was paralleled by an upregulation of the MSC marker genes for osteoblast differentiation, collagen type I and alkaline phosphatase. In addition, polyP, applied as Zn-polyP microparticles ("Zn-a-polyP-MP"), showed a distinct inhibitory effect on growth of Streptococcus mutans, in contrast to a toothpaste containing the broad-spectrum antibiotic triclosan that only marginally inhibits this cariogenic bacterium. Moreover, we demonstrate that the "a-polyP/RA-MP"-containing toothpaste efficiently repairs cracks/fissures in the enamel and dental regions and reseals dentinal tubules, already after a five-day treatment (brushing) of teeth as examined by SEM (scanning electron microscopy) and semi-quantitative EDX (energy-dispersive X-ray spectroscopy). The occlusion of the dentin cracks by the microparticles turned out to be stable and resistant against short-time high power sonication. Our results demonstrate that the novel toothpaste prepared here, containing amorphous polyP microparticles enriched with retinyl acetate, is particularly suitable for prevention/repair of (cariogenic) damages of tooth enamel/dentin and for treatment of dental hypersensitivity. While the polyP microparticles function as a sealant for dentinal damages and inducer of remineralization processes, the retinyl acetate acts as a regenerative stimulus for collagen gene expression in cells of the surrounding tissue, the periodontium.

Buccal Dosage Forms: General Considerations for Pediatric Patients

The development of an appropriate dosage form for pediatric patients needs to take into account several aspects, since adult drug biodistribution differs from that of pediatrics. In recent years, buccal administration has become an attractive route, having different dosage forms under development including tablets, lozenges, films, and solutions among others. Furthermore, the buccal epithelium can allow quick access to systemic circulation, which could be used for a rapid onset of action. For pediatric patients, dosage forms to be placed in the oral cavity have higher requirements for palatability to increase acceptance and therapy compliance. Therefore, an understanding of the excipients required and their functions and properties needs to be particularly addressed. This review is focused on the differences and requirements relevant to buccal administration for pediatric patients (compared to adults) and how novel dosage forms can be less invasive and more acceptable alternatives.

Treatment of Radiation-Induced Oral Mucositis Using a Novel Accepted Taste of Prolonged Release Mucoadhesive Bi-medicated Double-Layer Buccal Films

The aim of this study was to develop a novel double-layer bi-medicated prolonged release mucoadhesive buccal film (MBF) containing lidocaine hydrochloride (LC) and diclofenac potassium (DK). The ultimate goal of the prepared system is the treatment of radiation-induced oral mucositis pain with improved patient acceptance. MBFs were prepared using 3 × 2² randomized full factorial design for film optimization. Nanoemulsion system (NES) was used to mask DK bitter taste. The prepared films were characterized, viz thickness, mass uniformity, surface pH, folding endurance, swelling studies, ex vivo bioadhesive strength, in vitro drug release, and ex vivo permeation. The in vivo evaluation was carried out by testing the anti-inflammatory and analgesic activities on rats followed by a clinical study on patients to prove their acceptance. The optimized MBF composed of 10% w/w HPMC-4KM, 50 mg LC, and 50 mg DK-NES was selected due to prolonged in vitro drug release pattern and ex vivo permeability (95.24 ± 2.14 and 93.48 ± 3.24% in 6 h, respectively). MBF exposed a strong anti-inflammatory effect from 61 to 87% inhibition with a strong analgesic effect when compared to DK® and LC®, respectively. The clinical study revealed that films were accepted by the patients, and the presence of LC on the outer side helped in pain feeling reduction while DK-NES in the inner side facilitated in rapidly relieving the inflammation effect.

Oral health of children with attention deficit hyperactivity disorder

This study assessed and compared oral health and oral-health behaviours among children with and without attention deficit hyperactivity disorder (ADHD). The study included 31 children, 12-18 yr of age, with ADHD and 31 age- and gender-matched children without ADHD. Clinical data were recorded by a trained and calibrated examiner for caries, traumatic dental injuries, periodontal health, tooth wear, and salivary function. A questionnaire was also given to parents or caregivers about the oral health habits and behaviours of these children. Data were compared using Mann-Whitney U-tests and chi-square tests. No significant differences were found between children, with or without ADHD, in caries extent or prevalence, dental trauma prevalence, prevalence of periodontal disease or plaque, tooth wear, or unstimulated salivary flow. Children with ADHD had a significantly higher percentage of sites with gingival bleeding, as well as a higher frequency of parent-reported dislike of dentists, bruxism, history of assisted toothbrushing, and toothbrushing duration <1 min. They also had higher attendance at government dental clinics. The findings indicate that children with ADHD have poorer oral hygiene and more adverse oral-health attitudes and behaviours than do children without ADHD.