The effect of coating chitosan from cuttlefish bone (Sepia Sp.) on the surface of orthodontic mini-screw

Peri-implantitis is a significant complication resulting from the failure of orthodontic mini-screws. Recent strategies to address this issue include the application of natural antibacterial coatings to prevent bacterial colonization. Notably, cuttlefish ( Sepia sp.) bones are rich in chitosan, which is recognized for its antibacterial effectiveness and biocompatibility. To evaluate the effects of a chitosan coating derived from cuttlefish bone ( Sepia sp . ) on mini-screws against Aggregatibacter actinomycetemcomitans bacteria frequently linked to peri‑implantitis. The surface functional groups, phase composition, and crystal morphology of chitosan were analyzed using conventional analytic techniques alongside energy-dispersive X-ray analysis. These prepared were tested for antibacterial activity against A. actinomycetemcomitans by disk diffusion assay; minimum bactericidal concentration (MBC) and minimum inhibitory concentration (MIC) were determined. Stainless steel mini-screws were coated with chitosan, and their surfaces were characterized using scanning electron microscopy (SEM). The investigation revealed that chitosan exhibited a MIC value of 8 ppm against A. actinomycetemcomitans with MBCs recorded at 16 ppm. Zones of inhibition varied based on concentration; notably, concentrations at 0.4 %, 0.6 %, and 0.8 % produced zones averaging 16.17 ± 1.64 mm collectively while increasing to a mean zone size of 20.99 ± 3.63 mm at the highest tested concentration (0.8 %). SEM analyses further confirmed the successful adhesion of the chitosan compound onto immersed mini-screw surfaces. The prepared chitosan from cuttlefish bone (Sepia sp. ) has antibacterial activity against the bacteria A. actinomycetemcomitans in vitro and can successfully coat SS mini-screws to enhance their efficiency.