Evaluation of dentinal microcracks after sonic and ultrasonic agitation in diabetic teeth using micro-computed tomography: An in vitro study

Introduction: Diabetes mellitus alters dentin structure and mineral composition, increasing fracture susceptibility; therefore, this in vitro study aimed to evaluate dentinal microcrack formation in diabetic teeth following sonic and ultrasonic irrigant agitation using micro-computed tomography (micro-CT). Materials and Methods: Fifty diabetic single-rooted teeth were selected, stored in 0.1% thymol, and embedded in acrylic with silicone rubber to simulate the periodontal ligament. Root canal instrumentation was performed using ProTaper Ultimate files with 3 mL of 5.25% sodium hypochlorite and 2 mL of 17% ethylenediaminetetraacetic acid irrigation, followed by agitation with either Smart Lite Pro Endo Activator (SLP-EA) or UltraX. Post-instrumentation, canals were scanned using micro-CT to detect microcracks. Samples were split, dehydrated through graded ethanol, sputter-coated, and examined under a scanning electron microscope (SEM) to assess the dentinal surface changes. The Mann–Whitney U test and descriptive statistics were used to compare dentinal crack incidence and microcrack lengths between UltraX and SLP-EA groups. Results: A total of 25,350 micro-CT slices per group were analyzed, revealing significantly more microcracks in the UltraX group ( n = 110) than the SLP-EA group ( n = 36; P = 0.000 *). Microcracks were most prominent in the coronal third in both groups but extended deeper in the UltraX group. SEM confirmed greater dentinal damage with pits and cracks in the ultrasonic group, whereas the SLP-EA group showed minimal surface changes. Conclusion: Employing SLP-EA sonic device in activating irrigation resulted in fewer microcracks and better dentinal preservation in diabetic teeth compared to the UltraX ultrasonic system.