Abstract: A method of manufacturing a laser irradiation device for oral treatment includes (a) molding a base frame having a tongue fixing frame part convexly formed upward so that the tongue is inserted into a lower space thereof and a teeth seating part concavely formed so that human teeth are seated therein, (b) assembling an LED strip with respect to the base frame, the LED strip having a plurality of laser diodes installed on a flexible circuit board to correspond to the shape of the base frame, (c) injecting a liquid light-transparent resin material into an upper light-transparent cover and a lower light-transparent cover respectively corresponding to the shapes of upper and lower parts of the base frame, and (d) respectively pressing the upper light-transparent cover and the lower light-transparent cover vertically upward and downward with respect to the base frame.

Abstract: A needleless pain-free injection device according to the present disclosure includes a valve body, a valve member provided in an internal space of the valve body and airtightly sliding along the valve body, a liquefied gas container communicating with the internal space of the valve body and detachably coupled, at one end thereof, to the valve body, an operating knob provided on the exposed end of the valve member, a cylinder body coupled to one side of the valve body and having an internal space, a piston member provided such that one end thereof slides in the internal space of the cylinder body and having a piston rod, an injection unit provided with an injection piston rod coupled to the piston rod, and a gas passage forming means for selectively establishing and blocking the communication of the valve body and the cylinder body with outside air.

Abstract: A needleless pain-free injection device according to the present disclosure includes a valve body, a valve member provided in an internal space of the valve body and airtightly sliding along the valve body, a liquefied gas container communicating with the internal space of the valve body and detachably coupled, at one end thereof, to the valve body, an operating knob provided on the exposed end of the valve member, a cylinder body coupled to one side of the valve body and having an internal space, a piston member provided such that one end thereof slides in the internal space of the cylinder body and having a piston rod, an injection unit provided with an injection piston rod coupled to the piston rod, and a gas passage forming means for selectively establishing and blocking the communication of the valve body and the cylinder body with outside air.