The Philips Sonicare DiamondClean Smart 9750 uses high-frequency sonic vibration (62,000 brush strokes/min) that generates fluid dynamics reaching between teeth and below the gumline — areas the brush head doesn't physically touch. Its BrushSync technology detects which replacement head is attached and automatically selects the optimal cleaning mode. Five modes including a dedicated "Gum Health" mode with gentler pressure protocol. Best choice for patients with sensitive gums or post-periodontal surgery recovery.