A method of treating gum disease using a soft tissue diode laser which generates a beam of light having a wavelength in the visible portion of the electromagnetic spectrum (400nm - 700nm) at a laser power of 0.5 to 1.2 watts, used with intermittent stops to control tissue temperature, to decontaminate the gum tissue and biostimulate the periodontium nonsurgically when used with a substrate, thus preventing the long junctional epithelium from migrating into the sulcus, preserving tissue height, and regenerating periodontium, the method comprising: placing the tip of the laser inside the sulcus； penetrating the entire sulcus by moving the laser light with intermittent stops to control tissue temperature vertically and horizontally throughout the sulcus； and placing a substrate in the sulcus prior to a blood clot forming, thus regenerating periodontium in the sulcus.
