The present invention relates to a handheld dental device that provides photodynamic therapy. The device of the present invention may have an elongated housing an applicator tip extending from the distal end of the housing wherein the applicator tip has a lumen defined by a wall an optic fiber extending through the lumen of the applicator tip at least one power source attached to or residing within the housing at least one light source that provides light to the optic fiber and emits a wavelength that ranges from about 650 nm to about 1400 nm and at least one oxygen source that provides oxygen to a passage that communicates with the oxygen source and the applicator tip. Oxygen and light may be provided at the applicator tip simultaneously. The device may be used to eliminate or reduce bacteria which cause oral disease or conditions, such as endodontic treatment failures.
