Bioactive glass in the treatment of chronic osteomyelitis in children: Description of four consecutive cases and literature review

Dead space management strategies in the treatment of chronic osteomyelitis: a retrospective review

PURPOSE

Dead space management is critically important during the treatment of chronic osteomyelitis. Many dead space management strategies are available, each with their respective advantages and shortcomings. This study aims to present the outcomes and complications of dead space management strategies employed in the treatment of chronic osteomyelitis at a single tertiary level musculoskeletal unit.

METHODS

A retrospective review of dead space management strategies employed at a tertiary-level musculoskeletal infection unit was conducted. Patients of any age treated for chronic osteomyelitis of the appendicular skeleton with a minimum follow-up of 6 months were included in the study. Data were collected regarding patient demographics, aetiology and site of infection, dead space management strategy employed, follow-up period and outcome in terms of resolution of infection.

RESULTS

A final cohort of 132 patients underwent surgical treatment with a dedicated dead space management strategy for chronic osteomyelitis of the appendicular skeleton. Eleven patients (8%) experienced a recurrence of infection. Seven patients (63%) with recurrence were type B hosts, while four patients (37%) were type A hosts.

CONCLUSION

Dead space management is an integral part of treating chronic osteomyelitis; however, no guidelines currently exist regarding the most appropriate strategy. Favourable results are achievable in low to middle-income countries, and it is evident that no dead space management strategy is superior to another. The pursuit for the ideal void filler is ongoing.

LEVEL OF EVIDENCE

III.

Trends and perspectives on the commercialization of bioactive glasses

At least 25 bioactive glass (BG) medical devices have been approved for clinical use by global regulatory agencies. Diverse applications include monolithic implants, bone void fillers, dentin hypersensitivity agents, wound dressing, and cancer therapeutics. The morphology and delivery systems of bioactive glasses have evolved dramatically since the first devices based on 45S5 Bioglass®. The particle size of these devices has generally decreased with the evolution of bioactive glass technology but primarily lies in the micron size range. Morphologies have progressed from glass monoliths to granules, putties, and cements, allowing medical professionals greater flexibility and control. Compositions of these commercial materials have primarily relied on silicate-based systems with varying concentrations of sodium, calcium, and phosphorus. Furthermore, therapeutic ions have been investigated and show promise for greater control of biological stimulation of genetic processes and increased bioactivity. Some commercial products have exploited the borate and phosphate-based compositions for soft tissue repair/regeneration. Mesoporous BGs also promise anticancer therapies due to their ability to deliver drugs in combination with radiotherapy, photothermal therapy, and magnetic hyperthermia. The objective of this article is to critically discuss all clinically approved bioactive glass products. Understanding essential regulatory standards and rules for production is presented through a review of the commercialization process. The future of bioactive glasses, their promising applications, and the challenges are outlined. STATEMENT OF SIGNIFICANCE: Bioactive glasses have evolved into a wide range of products used to treat various medical conditions. They are non-equilibrium, non-crystalline materials that have been designed to induce specific biological activity. They can bond to bone and soft tissues and contribute to their regeneration. They are promising in combating pathogens and malignancies by delivering drugs, inorganic therapeutic ions, and heat for magnetic-induced hyperthermia or laser-induced phototherapy. This review addresses each bioactive glass product approved by regulatory agencies for clinical use. A review of the commercialization process is also provided with insight into critical regulatory standards and guidelines for manufacturing. Finally, a critical evaluation of the future of bioactive glass development, applications, and challenges are discussed.

Interaction of Ceramic Implant Materials with Immune System

The immuno-compatibility of implant materials is a key issue for both initial and long-term implant integration. Ceramic implants have several advantages that make them highly promising for long-term medical solutions. These beneficial characteristics include such things as the material availability, possibility to manufacture various shapes and surface structures, osteo-inductivity and osteo-conductivity, low level of corrosion and general biocompatibility. The immuno-compatibility of an implant essentially depends on the interaction with local resident immune cells and, first of all, macrophages. However, in the case of ceramics, these interactions are insufficiently understood and require intensive experimental examinations. Our review summarizes the state of the art in variants of ceramic implants: mechanical properties, different chemical modifications of the basic material, surface structures and modifications, implant shapes and porosity. We collected the available information about the interaction of ceramics with the immune system and highlighted the studies that reported ceramic-specific local or systemic effects on the immune system. We disclosed the gaps in knowledge and outlined the perspectives for the identification to ceramic-specific interactions with the immune system using advanced quantitative technologies. We discussed the approaches for ceramic implant modification and pointed out the need for data integration using mathematic modelling of the multiple ceramic implant characteristics and their contribution for long-term implant bio- and immuno-compatibility.