Biodegradable polymers are considered important modern materials in the fields of materials engineering and biomedical science due to their ability to gradually degrade inside the human body while providing biocompatibility and suitable mechanical properties. These materials are used in various medical applications, including tissue engineering, drug delivery, wound healing, orthopedic implants, and surgical sutures. This article aims to review the main types of biodegradable polymers, their properties, degradation mechanisms, major applications, and the challenges associated with their use. Keywords: Biopolymers, Biodegradation, Medical Applications, Biocompatibility, Tissue Engineering. 1. Introduction Biodegradable polymers have attracted increasing attention in recent years due to their applications in the development of modern medical materials. These polymers are characterized by their ability to degrade inside the human body through chemical and enzymatic reactions, reducing the need for surgical removal of certain temporary implants. The selection of a suitable polymer depends on its mechanical properties, degradation rate, and compatibility with living tissues. 2. Types of Biodegradable Polymers Biodegradable polymers are divided into two main categories: First: Natural Polymers • Chitosan: Characterized by biocompatibility and antimicrobial properties, and used in wound dressings. • Collagen: Used in tissue and bone regeneration. • Gelatin: Used in the production of hydrogels and drug delivery systems. • Alginate: Used in wound dressings and cell encapsulation. Second: Synthetic Polymers • PLA (Polylactic Acid): Used in medical implants and surgical sutures. • PGA (Polyglycolic Acid): Used in absorbable surgical sutures. • PCL (Polycaprolactone): Used in tissue engineering and orthopedic applications. • PLGA (Poly(lactic-co-glycolic acid)): Used in drug delivery systems and medical implants. 3. Biodegradation Mechanisms These polymers primarily degrade through two mechanisms: 1. Hydrolytic Degradation: Occurs when water reacts with chemical bonds within polymer chains, leading to their breakdown. 2. Enzymatic Degradation: Occurs through the action of biological enzymes on the polymer structure. The degradation rate is influenced by several factors, including molecular weight, degree of crystallinity, chemical composition, temperature, and water absorption. 4. Medical Applications Biodegradable polymers are used in several medical fields, including: • Tissue Engineering: Manufacturing porous scaffolds that support cell growth and tissue regeneration. • Drug Delivery: Controlling the gradual release of therapeutic drugs. • Orthopedic Applications: Manufacturing temporary medical implants and screws. • Wound Healing: Producing medical dressings that support the healing process. • Surgical Sutures: Manufacturing sutures that can be absorbed by the body. 5. Advantages and Challenges Biodegradable polymers offer several advantages, including biocompatibility, controllable degradation rates, ease of processing, and a wide range of medical applications. However, they also face certain challenges, such as limited mechanical strength in some polymer types, difficulties in precisely controlling degradation rates, and the potential effects of degradation products on surrounding tissues. 6. Future Developments Recent research has focused on developing polymer composites by combining natural and synthetic polymers with nanomaterials to improve their mechanical and biological properties. In addition, three-dimensional printing technologies contribute to the fabrication of advanced medical scaffolds tailored to specific patient needs. 7. Conclusions Biodegradable polymers represent a promising direction in materials engineering and medical applications due to their distinctive properties and their potential use in tissue regeneration, drug delivery, and medical implant manufacturing The development of polymer composites and the improvement of their mechanical properties and degradation rates are among the most important future research directions for expanding their applications in modern medicine.