A self-purging system (10) for administering a hydrogel composition (16) formed by mixing the first and second liquid components (12, 14) comprising, an applicator (30) dimensioned and configured to mix the first and second liquid components (12, 14) and form the hydrogel composition (16), the applicator (30) including the inlet paths (34, 36) that transport the first and second liquid components (12, 14) subjected to an application pressure P (A) selectively applied to an outlet path (40) to mix and form the hydrogel composition (16) for discharge from the outlet path (40), and a purge assembly (42) comprising a source (44) of liquid washing agent (46) subjected to a constant applied purge pressure P (P) that is maintained at a magnitude that is less than P (A), and a purge path (48) that couples the source (44) to the output path (40) for trans Porting the liquid flushing agent (46) to the outlet path (40) subjected to the constantly applied purge pressure P (P), including the purge assembly (42) plus a set of valves that communicate with the purge path (48) and outlet path (40) and which can operate in response to localized pressure states in the first and second flow states, the first flow state allows the flow and mixing of the first liquid components and second (12), 14) but not of the liquid washing agent (46) in the outlet path (40) during the application of P (A), to dispense the hydrogel composition (16) from the outlet path ( 40), the second flow state allows the liquid flushing agent (46) to flow, but not the first and second liquid components (12, 14) in the outlet path (40), subjected to the applied purge pressure constantly P (P), for the continuous washing of the residual hydrogel composition (16) of the outlet path (40), automatically placing the valve assembly in the first flow state in response to localized pressure states whenever P (A) is applied, and placing automatically the valve assembly in the second flow state in response to localized pres
