Abstract
Synthetic calcium phosphate (CaP) ceramics represent the most widely used biomaterials for bone regenerative treatments due to their biological performance that is characterized by bioactivity and osteoconductive properties. From a clinical perspective, injectable CaP cements (CPCs) are highly appealing, as CPCs can be applied using minimally invasive surgery and can be molded to optimally fill irregular bone defects. Such CPCs are prepared from a powder and a liquid component, which upon mixing form a paste that can be injected into a bone defect and hardens in situ within an appropriate clinical time window. However, a major drawback of CPCs is their poor degradability. Ideally, CPCs should degrade at a suitable pace to allow for concomitant new bone to form. To overcome this shortcoming, control over CPC degradation has been explored using multiple approaches that introduce macroporosity within CPCs. This strategy enables faster degradation of CPC by increasing the surface area available to interact with the biological surroundings, leading to accelerated new bone formation. For a comprehensive overview of the path to degradable CPCs, this review presents the experimental procedures followed for their development with specific emphasis on (bio)material properties and biological performance in pre-clinical bone defect models.
Highlights
Bone possesses the intrinsic capacity for regeneration as part of the repair process in response to injury [1,2], but only if a defect is below the so-called critical size [3] and if bone healing is not impaired by local or systemic comorbidities [4,5,6]
Because HA is the most stable Calcium phosphate (CaP) phase above pH 4.4, most Calcium phosphate cements (CPCs) formulations form HA or a closely related apatitic phase as the end-product [56,57]. Another option for CPC hardening is the mixture of the powder phase with a liquid solution that contains a carboxylic acid, which reacts with the calcium compounds and produces fast hardening cements [29,58,59]
Efforts have been focused on the following approaches; foaming agents, rapid prototyping or incorporation of water-soluble or polymeric porogens
Summary
Calcium phosphate cements (CPCs) represent one of the most widely studied materials for bone regeneration due to their numerous benefits such as injectability or moldability. Their slow degradation rate has put the focus of many researches on improving their degradation mainly by enhancing their macroporosity. This article reviews the main techniques to enhance macroporosity of CPCs, the benefits and drawbacks of each technique as well as the recent advances in enhancing this macroporosity
Sign-in/Register to view highlights & summary Talk to us
Join us for a 30 min session where you can share your feedback and ask us any queries you have
Schedule a callDisclaimer: All third-party content on this website/platform is and will remain the property of their respective owners and is provided on "as is" basis without any warranties, express or implied. Use of third-party content does not indicate any affiliation, sponsorship with or endorsement by them. Any references to third-party content is to identify the corresponding services and shall be considered fair use under The CopyrightLaw.
