Methods and apparatuses for treating a root canal in a tooth or hard and/or soft tissue within a tooth and surrounding tissues by pulsing a laser light into a reservoir, preferably after introducing liquid fluid into the reservoir, so as to disintegrate, separate, or otherwise neutralize pulp, plaque, calculus, and/or bacteria within and adjacent the fluid reservoir without elevating the temperature of any of the dentin, tooth, bones, gums, other soft tissues, other hard tissues, and any other adjacent tissue more than about 5° C.