Abstract: Subjects treated with nonablative fractional photothermolysis (FP) have an intact stratum corneum, but can have microscopic lesions and vacuole formation within the epidermis. The vacuoles thus formed can trap dermal material and extrude it through the epidermis. Thus, FP can be used for the treatment of recalcitrant melasma, solar elastosis, and tattoos.

Abstract: A mechanical element allows the tip of the handpiece of a dermatological treatment system to rotate to adjust for deviations in handpiece angle with respect to the surface of the treatment area. The tip may glide over the surface of the skin, the tip may include wheels or rotating cylinders on which the tip rolls across the skin, or the tip may be removed from the skin and placed in a new location in a stamping motion. The tip of the handpiece rotates around a single axis, or around two perpendicular axes, so that pressure on the tip moves the flat surface of the tip into proper orientation for planar contact with the skin. An element can be included in the handpiece to apply a restoring force on the tip so that the tip rests in its optimal position in the absence of external forces.