Implant in ection is a serious complication resulting in pain, mortality, prolonged recovery, and antimicrobial resistance (AMR). Reducing the risk-o -in ection associated with tissue implants require imminent attention, where pure silver (Ag) o ers enormous potential. However, the printability, mechanical per ormance nor microbial resistance o additively manu actured (AM) pure Ag is unavailable in literature. This is critical as Ag is thought to play a vital role in the development o AM patient-speci ic in ection resistant implants in the decade to come. The study there ore additively manu actured 99.9% pure-Ag through selective laser melting (SLM) and systematically investigates its mechanical per ormance. The validated SLM process parameters were then used to conceive two ully porous bone sca old each at approximately 68 and 90% (wt.) porosity. While the study brings to attention the potential de ects in SLM pure-Ag through X-ray nanotomography (Xray nCT), the mechanical properties o porous Ag sca olds were ound to be similar to cancellous bone. The study achieved the highest SLM pure-Ag density o 97% with Young's modulus (E), elastic limit ( ), yield strength ( ), ultimate strength ) and ultimate strain ) in the range o 15. MPa and 0.07-0.10 respectively. The antimicrobial e icacy o printed silver was tested against the common implant in ection-causing Staphylococcus aureus and led to 90% and 99.9% kill in 4 and 14 hours respectively.The study, there ore, is a irst step towards achieving a new generation Ag-based AM in ection resistant porous implants.

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Oropharyngeal candidiasis (OPC) is a mucosal infection caused by Candida spp., and it is common among the immunocompromised. This condition is mainly treated using oral antifungals. Chlorhexidine (CHD) is a fungicidal and is available as a mouth wash and oral gel. It is used as an adjuvant in the treatment of OPC due to the low residence time of the current formulations. In this study, its activity was tested against C. albicans biofilm and biocompatibility with the HEK293 human cell line. Then, it was formulated as mucoadhesive hydrogel buccal tablets to extend its activity. Different ratios of hydroxypropyl methylcellulose (HPMC), poloxamer 407 (P407), and three different types of polyols were used to prepare the tablets, which were then investigated for their physicochemical properties, ex vivo mucoadhesion, drug release profiles, and the kinetics of drug release. The release was performed using Apparatus I and a controlled flow rate (CFR) method. The results show that CHD is biocompatible and effective against Candida biofilm at a concentration of 20 µg/mL. No drug excipient interaction was observed through differential scanning calorimetry (DSC) and Fourier-transform infrared spectroscopy (FTIR). The increase in P407 and polyol ratios showed a decrease in the swelling index and an increase in CHD in vitro release. The release of CHD from the selected formulations was 86–92%. The results suggest that chlorhexidine tablets are a possible candidate for the treatment of oropharyngeal candidiasis.

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In the current work, two groups of chlorhexidine mucoadhesive buccal tablets were prepared, using either rod or irregularly-shaped spherical particles of hydroxypropyl methylcellulose and different ratios of poloxamer 407 (P407). The tablets were designed to release the drug over two hours. Their physicochemical properties and drug release profiles were investigated. The impact on dry granulation, the ex-vivo mucoadhesion, the swelling index, the morphology of swollen tablets and the drug release kinetic were investigated. Drug-polymers chemical interaction was studied using Fourier Transforms Infrared Spectroscopy (FTIR) and differential scanning calorimetry (DSC). Due to different particle shapes, the preparation of dry granules required a 40 KN force for rod-shaped particles compared to 10 KN for the irregularly-shaped spherical particles. All formulations showed at least two-hours residence time using ex-vivo mucoadhesion. Statistically, there was no significant difference in the swelling index, drug release nor its kinetic for both groups. However, the microscopical morphology of the swollen tablet and the size of the pores were affected by particle shape. Increasing the ratio of P407 to 62.5% resulted in a pronounced increase in drug release from around 60% to >90% after two hours. Following the FTIR and DSC analyses, no chemical interaction was noted apart from the steric hindrance effect of P407, which was observed even with the physical mixtures.