Figure 4From: Biophysical characterization of low-frequency ultrasound interaction with dental pulp stem cellsSnapshots of pressure and intensity plots of (45 kHz, 31 kPa) ultrasonic wave throughout the tooth.(a) Pressure at t = 1 μs and ( b ) intensity at t = 3.35 μs. It shows high-intensity concentration in pulp (arrow) (Additional file2).Back to article page