bioresorbables

Bioresorbables are materials designed to degrade and be absorbed by the body after fulfilling their function. They are used in medical devices and drug delivery systems to provide temporary mechanical support or therapeutic action without requiring removal. They include synthetic polymers such as polylactic acid (PLA), polyglycolic acid (PGA), their copolymer PLGA, and polycaprolactone (PCL); natural materials like collagen, gelatin, chitosan; and inorganic or bioactive components such as calcium phosphates or bioactive glasses.

Degradation occurs through hydrolysis of ester bonds in polymers and, for natural materials, enzymatic breakdown. Degradation rates depend on molecular weight, crystallinity, hydrophilicity, device geometry, surface area, local pH, and tissue response. Time scales range from weeks to years, with the mechanical properties designed to match the healing process.

Common applications include absorbable sutures; fixation devices in orthopedics and dentistry; stents that gradually dissolve; drug-delivery implants and tissue engineering scaffolds; ocular implants. The resorption products are typically metabolized and eliminated via natural pathways (for example, lactic and glycolic acid from PLA/PGA).

Advantages include eliminating the need for a second procedure to remove implants, reducing long-term foreign material load, and potentially improved imaging compatibility. Challenges include variable degradation in vivo, possible inflammatory responses or acidity at the site, premature loss of mechanical strength, and manufacturing or sterilization constraints.

In clinical practice, bioresorbables have gained widespread use across soft tissue repair, orthopedics, cardiology, and ophthalmology. Ongoing research seeks to tailor degradation kinetics to specific tissues, develop new composite materials, and expand applications in controlled drug delivery and regenerative medicine.