Fig. 3

Measurement of tooth extraction forces in porcine jaw. A The first and second porcine mandibular premolar teeth were split to form four roots labeled as T1, T2, T3 and T4. Following 16 h from the injection of ColG or its variant, the extraction was performed using the tensile strength testing machine along the longitudinal axes of each extracted root, and the force vs. displacement was recorded. B Mean and dispersion of extraction forces of ColG (blue) and ColG-variant (red). Each contralateral pair of roots is marked by black circles and connective lines, and the horizontal line marks the mean force for each root. Statistically significant values are indicated above each paired data, *:p < 0.01, **:p < 0.001