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Changing relative humidity levels challenge the manufacturing of chewable xylitol-sorbitol based tablets. The aim of the study is to investigate how the formulation of chewable xylitol-sorbitol tablets affects the properties of the powder blends and the tablets in an environment of different relative humidity levels. In all, 30 batches containing different ratios of sorbitol, xylitol and magnesium stearate were prepared at three different relative humidity levels. Powder blends were made into tablets using an instrumented eccentric tableting machine. To demonstrate the effect of variables on powder blend and tablet properties, multiple linear regression analysis was performed. It was found that xylitol-sorbitol powder blends and tablets benefitted from the large amount of magnesium stearate, and the high lubricant level negatively affected the quality of the tablets only at high relative humidity. In the presence of high environmental humidity, the amount of sorbitol in the powder mixture must be limited in order to prevent sticking whereas at low relative humidity, higher content of sorbitol is needed to decrease the friability of tablets. Results indicate that alternating relative humidity levels truly challenge the production of xylitol-sorbitol based tablets and if the humidity is not controllable, there is a need for additional filler-binders., (Copyright © 2021 The Author(s). Published by Elsevier B.V. All rights reserved.)

Biofilms play a pivotal role in the progression of periodontitis and they can be treated with antiseptics (i.e. chlorhexidine) or antibiotics, but these therapeutic alternatives are unable of ameliorating periodontal alveolar bone loss, which has been, on the other hand, successfully treated with bone-preserving agents. The improved bone formation achieved in animal models by the combination of two such agents: bioactive glass (BAG) and bisphosphonates has attracted the interest for further exploring dental applications. However, the antimicrobial effects that may result from combining them have not been yet investigated. Here, our aim was to explore the anti-biofilm effects that could result from combining BAG with bisphosphonates, particularly in a dental biofilm model. The experiments were performed with an oral cavity single-specie (Aggregatibacter actinomycetemcomitans) biofilm assay, which was optimized in this contribution. Risedronate displayed an intrinsic anti-biofilm effect, and all bisphosphonates, except clodronate, reduced biofilm formation when combined with BAG. In particular, the anti-biofilm activity of risedronate was significantly increased by the combination with BAG. Since it has been proposed that some of the antimicrobial effects of BAG are caused by local pH changes, studies of pH variations were performed to gain a mechanistic understanding. However, the observed anti-biofilm effects could not be explained with lowered pHs. Overall, these results do provide further support for the promising use of bisphosphonate-BAG combinations in dental applications. These findings are particularly relevant for patients undergoing cancer chemotherapy, or osteoporotic patients, which are known to be more vulnerable to periodontitis. In such cases, bisphosphonate treatment could play a double positive effect: local treatment of periodontitis (in combination with BAG) and systemic treatment of osteoporosis, prevention of hypercalcemia and metastases., (Copyright © 2016 Elsevier B.V. All rights reserved.)

Adsorption of proteins and adhesion of bacteria to a surface is affected by chemical and physical interactions. In this study, polymer coatings and their ability to adsorb avidin and Staphylococcus aureus were investigated. The surface chemistry and topography of the polymer coatings was modified by changing the weight ratio of the hydrophobic polystyrene (PS) and the hydrophilic acrylonitrile butadiene styrene (ABS) components in the polymer blend. Avidin adsorbed less to the ABS phase compared with the PS phase. The side-on orientation of avidin on the ABS surface, however, resulted in a higher specific binding of biotinylated bovine serum albumin. Steric effects and hydrophobic protein-surface interactions decreased the activity of avidin on the PS phase. The increased hydrophobicity and roughness of the polymer coatings enhanced the adhesion of S. aureus. The avidin-coated latex surface with 55% relative surface coverage of the PS phase showed anti-microbial behavior., (Copyright © 2015 Elsevier B.V. All rights reserved.)