Compressive, Dimensional, and Antimicrobial Characteristics of 3D-Printed Acrylonitrile Butadiene Styrene (ABS) Following Dental Disinfection

Objective: To investigate the compressive, dimensional, and antimicrobial properties of thermoplastic Acrylonitrile Butadiene Styrene (ABS) 3D printed hollow blocks following chemical disinfection. Methods: Forty-two 3D printed ABS cubes were immersed in tap water, 0.12% chlorhexidine gluconate, 3% hydrogen peroxide, 5% sodium bicarbonate, 0.5% sodium hypochlorite, and commercial Potassium Caroate (Polident) for 28 days (4 cycles). Linear Outer (OM) and Inner (IM) dimensions, Root Mean Square (RMS), and mass were recorded before and after each immersion cycle. An additional set of seven cubes was untreated and served as a control. Fourier transform infrared spectroscopy (FTIR) was executed on one randomly selected sample from each group before and after immersion. Following the completion of the immersion cycles, an evaluation of compressive strength was performed using a universal testing machine. Subsequently, from each group, a single ABS cube was randomly selected for the introduction of Streptococcus mutans and Candida albicans, followed by a 14-day incubation period with Scanning Electron Microscope (SEM) evaluation. Results: There were no significant differences (p > 0.05) between OM, IM, and compressive strength measurements (F = 1.036, p = 0.443) across all groups. RMS values increased for OM and decreased for IM. Notably, cubes that underwent immersion in a 0.12% chlorhexidine gluconate solution displayed considerable changes in mass (p < 0.05), exhibiting a low positive correlation (ρ = 0.339). The 0.12% chlorhexidine gluconate group exhibited the emergence of a new OH peak (3000–3500) in FTIR, whereas the 3% hydrogen peroxide group experienced the disappearance of the styrene peak (1300–1500). Exposure of ABS to C. albicans and S. mutans demonstrated clear surfaces under SEM with 0.12% chlorhexidine gluconate, 0.5% sodium hypochlorite, and Polident. Conclusions: Disinfection with 0.5% sodium hypochlorite and Potassium Caroate produced minimal mechanical changes and resisted growth of C. albicans and S. mutans. 0.12% chlorhexidine gluconate and 3% hydrogen peroxide altered dimensional and chemical compositions of 3D printed ABS following disinfection.