Electrical charge storage as a strategy to enhance the bioactivity of 45S5 bioglass

The implants have become one of the most used devices to replace missing teeth over the last decades, preserving and stimulating bone growth. However, complications during the osseointegration process can lead to bone loss and potential implant failure. Biomaterials, such as 45S5 Bioglass, have been used as coatings to accelerate the implant integration. The introduction of electrical charges in biomaterials creates a more bioactive surface, accelerating osseointegration and improving implant stability. In particular, negative charges promote osteogenic cell adhesion and inhibit Gram-negative bacteria colonization. The samples (bulk and pellet) were charged at 200 °C, varying the discharge time, using the corona discharge method. The thermally stimulated depolarization current (TSDC) analysis was used to measure the stored charge, identifying optimal charging times of 15′ for pellets and 30′ for bulk. The alternating current (AC) measurements show that pellets retain and release charge more effectively. The Atomic Force Microscopy (AFM) results revealed that longer charging durations resulted in an increase in surface electrical charge. Bioactivity tests further indicated that, although electrical charges did not directly trigger Ca-P layer formation, they significantly enhanced its uniformity at the bioactive glass surface during the initial hours in simulated body fluid (SBF). These results highlight the potential of 45S5 Bioglass in storing electrical charge to enhance the performance and longevity of dental implants when used as a coating.