Sterilization of PLA-based materials must preserve their mechanical integrity and physicochemical properties. Gamma irradiation is widely recognized as a suitable method for sterilizing PLA products, with numerous studies confirming its efficacy and safety at doses up to 25 kGy [6,7,8]. At this dose, composites such as hydroxyapatite/PLLA (HAp/PLLA) remain structurally stable. However, at significantly higher doses (e.g., 450 kGy), macroscopic surface damage has been observed, negatively affecting performance [13]. Alsabbagh et al. further demonstrated that high-dose irradiation (up to 175 kGy) substantially reduces tensile strength and elongation at break in PLA and compressed HDPE, supporting concerns over excessive irradiation [14].

Alternative sterilization methods, including UV irradiation and hydrogen peroxide plasma, have shown promise in sterilizing electrospun biodegradable matrices without altering their chemical composition or surface morphology [15]. However, these methods are limited to surface sterilization and may not ensure sterility within the internal volume of materials—a critical requirement for implantable scaffolds.

Electron beam sterilization is gaining traction due to its efficiency, speed, and compatibility with thermally sensitive materials. It is widely used for single-use medical devices and offers potential advantages for biodegradable polymer systems.

Leonard et al. examined PLA and PLGA materials irradiated with a 50 kGy electron beam from a 1.5 MeV accelerator, reporting a significant molecular weight reduction up to 5.4 mm depth, with no effect beyond that [16]. These findings highlight the tunability of electron beam parameters, enabling control over degradation kinetics and possibly enhancing biological integration at the surface level. Such effects could benefit osseointegration, which is critical for the success of resorbable implants.

Kang et al. investigated β-TCP/PCL composites and found that electron beam sterilization accelerated degradation without compromising volume stability [17]. This outcome is important clinically, as it supports consistent mechanical function during early healing phases. Similarly, Bruyas et al. showed that electron beam exposure improved the mechanical properties of PCL/β-TCP scaffolds by 14% and accelerated degradation by 25%, without reducing biocompatibility [18]. These findings underscore the potential of this method to enhance both mechanical function and resorption characteristics in maxillofacial scaffolds.

Our study expands upon these findings by evaluating the impact of e-beam sterilization on PLA, PLGA, and PLA/HAP composite systems. PLGA (60:40) samples, regardless of irradiation, lost around 40% of their mass within one month and exhibited pronounced structural degradation, rendering them unsuitable for extended use. This behavior aligns with previous work by Wu et al., who showed that a high glycolic acid content leads to rapid hydrolysis and dissolution in buffered environments [1].

In contrast, PLGA (85:15) samples maintained structural integrity for up to 2.5 months and lost only ~ 5% of their initial mass, independent of sterilization. This performance is consistent with findings by Auras et al., who demonstrated that decreasing the glycolic acid content slows degradation and improves material resilience [19].

Among all the tested materials, pure PLA and PLA/HAP composites exhibited the highest stability. Non-irradiated PLA/HAP samples showed greater variability in degradation (0–19% mass loss), while irradiated samples retained up to 98% of their original mass. The occasional slight mass increase is likely due to water diffusion into deeper matrix layers, a phenomenon also described by Chen et al. [20].

FTIR spectroscopy confirmed the absence of significant structural changes following 25 kGy electron beam sterilization in all tested materials. The spectra showed no new peaks or shifts, indicating the preservation of molecular structure. These results support previous studies, including Auras et al., which found similar outcomes following gamma sterilization of PLA [19].

The clinical potential of biodegradable polymers lies in their ability to serve as customized, resorbable scaffolds. While PLGA and its copolymers have been explored for applications ranging from jawbone reconstruction to tendon repair, biocompatibility and long-term in vivo safety remain key focus areas for ongoing investigation.

Sindeeva et al. tested PLA, PCL, and PLGA tracheal stent coatings in rabbits. None of the materials induced fibroblast cytotoxicity. SEM analysis revealed rapid PLGA degradation (within 10 days), partial degradation of PLA, and minimal change in PCL. The best healing outcomes occurred in tissues interfacing with PLGA, supporting its suitability for early-phase regeneration [21].

Mao et al. confirmed PLGA’s high biocompatibility and tunable mechanical and degradation properties, making it ideal for diverse tissue engineering applications [22]. Fujimaki and Lim tested PLGA-based stents for tendon repair and reported full degradation by week 12, without inflammatory responses and with near-native tissue regeneration [23, 24].

Ge et al. studied 3D-printed PLGA scaffolds in rabbits and observed progressive bone formation and maturation at 4, 12, and 24 weeks. The material demonstrated good biocompatibility and osteoconductivity in both periosteum and iliac crest placements [25].

In surgical applications, the mechanical performance of bioresorbable materials is just as critical as their biocompatibility. Adequate strength, stiffness, and controlled degradation are essential for maintaining implant stability throughout the healing process. Jiang et al. showed that PLA/HA screws outperform PLGA/β-TCP in pullout strength, deformation resistance, and structural retention. However, hydroxyapatite, while enhancing strength, slows degradation—a trade-off that must be considered clinically [26]. PLGA’s adjustable lactic-to-glycolic ratio allows for precise tuning of mechanical and degradation behavior, making it a versatile platform for varied surgical applications.

In conclusion, PLGA and its copolymers consistently exhibit strong potential for biodegradable implants. Animal studies confirm their biocompatibility, predictable degradation, and absence of inflammation, supporting their clinical translation across disciplines such as maxillofacial surgery, orthopedics, and soft tissue repair.

Our findings reinforce the feasibility of electron beam sterilization as a reliable method for PLA-based biomaterials. It preserves mechanical and chemical properties while achieving sterility. Future research will focus on evaluating the in vivo biological responses and long-term mechanical performance of these materials, ultimately guiding the development of next-generation scaffolds with optimized resorption profiles and clinical outcomes.