Controlled Impact Fragmentation of Extracted Teeth as a Novel Strategy for Dentin Graft Preparation: A Granulometric and Comparative Study.

Alveolar bone preservation following tooth extraction requires biomaterials with appropriate biological and physical properties. Here, particle size and morphology of the biomaterial play a critical role in bone regeneration. Tooth particle grafts represent a promising alternative because of their compositional similarity to bone; however, current dentin processing methods often lack standardization and produce heterogeneous particle populations. This study evaluated a novel impact-driven fragmentation system designed to produce dentin particles with controlled size distributions through adjustment of a predefined clearance distance. Fresh porcine teeth were fragmented under three operating conditions (250, 300, and 400 µm clearance distances). Particle characterization was performed using scanning electron microscopy (SEM), laser diffraction granulometric analysis, morphometric measurements of particle length and width, descriptive statistical analysis, and linear regression analysis to evaluate dimensional relationships. Laser diffraction analysis demonstrated that increasing clearance distance produced progressively larger particles, with volume mean diameters of 222, 289.6, and 356 µm for the 250, 300, and 400 µm conditions, respectively. The 300 µm condition generated the most homogeneous particle population, exhibiting the lowest span value (0.34) and the narrowest particle size distribution. SEM observations revealed elongated particles with consistent morphology across all conditions. Morphometric analysis confirmed proportional increases in particle length and width with increasing clearance distance, while aspect ratios remained relatively constant (2.02-2.37). Regression analysis showed a positive linear relationship between particle length and width, supporting a common fragmentation mechanism across all operating conditions. Controlled impact fragmentation enables predictable dentin particle production, allowing for particle size regulation through a defined mechanical parameter while preserving particle morphology. The 300 µm clearance condition provided the most favorable balance between particle size control and distribution homogeneity, suggesting that this approach may contribute to the standardized preparation of tooth-derived graft biomaterials for future bone regeneration applications.