A micro-bubble solution for use in a method of disinfecting a shaped root canal, wherein the micro-bubble solution is comprised of an oxygen carrier, an oxidizing agent and a surfactant, wherein the oxygen carrier is chosen from the group consisting of perfluorodecahydro naphthalene, perfluorodecalin, perfluorohexane, octafluoropropane, perfluorobutane, perfluorooctane, perfluoromethyldecalin and trans -carbonylchlorobis(triphenylphosphine)iridium, and combinations thereof; wherein the oxidizing agent is chosen from the group consisting of hydrogen peroxide (H 2 O 2), dilute sodium hypochlorite, dimethyl sulfoxide and chlorine dioxide and combinations thereof; and wherein, the surfactant is chosen from the group consisting of mineral oil, glycerol, polyethylene glycol, non-ionic detergent, polypropylene glycol, sodium dodecyl sulfate, a nonionic polyoxyethylene surfactant, cetrimide and combinations thereof; and wherein the method of disinfecting a shaped root canal comprises: a) introducing a photoactive solution into the root canal, the photoactive solution containing a photoactive compound dissolved in an alcohol carrier solution; b) removing excess photoactive solution from the root canal; c) introducing the micro-bubble solution into the root canal after completion of step b); d) mechanically, sonically or ultrasonically activating the micro-bubble solution in the canal to generate dissolved oxygen bubbles in the canal, wherein the surfactant stabilizes the micro-bubbles; and e) introducing light into the canal after or simultaneously with step d) to activate the photoactive compound, the activated photoactive compound releasing energy to the oxygen molecules to convert the oxygen molecules to singlet oxygen. wherein the oxygen carrier is chosen from the group consisting of perfluorodecahydro naphthalene, perfluorodecalin, perfluorohexane, octafluoropropane, perfluorobutane, perfluorooctane, perfluoromethyldecalin and trans -carbonylchlorobis(triphenylphosphine)iridium, and combinations thereof; wherein the oxidizing agent is chosen from the group consisting of hydrogen peroxide (H 2 O 2), dilute sodium hypochlorite, dimethyl sulfoxide and chlorine dioxide and combinations thereof; and wherein, the surfactant is chosen from the group consisting of mineral oil, glycerol, polyethylene glycol, non-ionic detergent, polypropylene glycol, sodium dodecyl sulfate, a nonionic polyoxyethylene surfactant, cetrimide and combinations thereof; and wherein the method of disinfecting a shaped root canal comprises: a) introducing a photoactive solution into the root canal, the photoactive solution containing a photoactive compound dissolved in an alcohol carrier solution; b) removing excess photoactive solution from the root canal; c) introducing the micro-bubble solution into the root canal after completion of step b); d) mechanically, sonically or ultrasonically activating the micro-bubble solution in the canal to generate dissolved oxygen bubbles in the canal, wherein the surfactant stabilizes the micro-bubbles; and e) introducing light into the canal after or simultaneously with step d) to activate the photoactive compound, the activated photoactive compound releasing energy to the oxygen molecules to convert the oxygen molecules to singlet oxygen. a) introducing a photoactive solution into the root canal, the photoactive solution containing a photoactive compound dissolved in an alcohol carrier solution; b) removing excess photoactive solution from the root canal; c) introducing the micro-bubble solution into the root canal after completion of step b); d) mechanically, sonically or ultrasonically activating the micro-bubble solution in the canal to generate dissolved oxygen bubbles in the canal, wherein the surfactant stabilizes the micro-bubbles; and e) introducing light into the canal after or simultaneously with step d) to activate the photoactive compound, the activated photoactive compound releasing energy to the oxygen molecules to convert the oxygen molecules to singlet oxygen.