Dental container and amalgam dispensing method

Claim 1

A dental container for receiving and separately storing at least two dental preparation ingredients until they are subsequently brought together and mixed within the container, for making a settable, semi-solid dental preparation ready for use, said container comprising: (a) a housing having a longitudinal axis, a filler opening at one end region of the housing, a discharge port at the opposite end region of the housing, a discharge port at the opposite end region of the housing, and interior wall portions bounding an interior multi-compartment chamber which extends longitudinally intermediate the filler opening and the discharge port, said chamber having a first storage compartment in which one of the ingredients is initially receivable, a second storage compartment in which the other of the ingredients is receivable, and a transfer compartment intermediate the storage compartments; (b) a longitudinally-extending plunger mounted within the chamber for londitudinal movement therealong, said plunger having a main shaft portion, an auxiliary shaft portion spaced londitudinally from the main shaft portion, and a reduced cross-section connecting shaft portion intermediate the main and auxiliary shaft portions; (c) first and second sealing means respectively mounted on the main and auxiliary shaft portions for joint movement therewith; (d) said plunger being manually movable in direction longitudinally of the chamber among (1) a filled position in which the first and second sealing means sealingly engage longitudinally spaced-apart wall portions of the chamber to thereby define in the circumambient region of the connecting shaft portion the first storage compartment wherein said one ingredient is sealingly contained prior to mixing, (2) a transfer position in which the second sealing means is disengaged from the wall portions bounding the first storage compartment, and in which the first and second storage compartments communicate with each other via the transfer compartment, to thereby permit transfer of said one ingredient through the transfer compartment and thereupon to the second storage compartment, and (3) a mix position in which the second sealing means sealingly engages wall portions of the chamber which are longitudinally spaced from the discharge port to define therebetween the second storage compartment wherein both ingredients are sealingly contained during mixing; (e) openable closure means at the discharge port for permitting discharge of the mixed ingredients upon opening of the closure means; (f) indicator means displayed on the plunger for visually indicating each of said filled, transfer and mix plunger positions to a dental operator; and (g) tactile sensory means for manually detecting each of said filled, transfer and mix plunger positions by the dental operator, said tactile sensory means including a plurality of grooves formed in the interior wall portions of the chamber for receiving at least one of the sealing means with snap-in locking action in each of said filled, transfer and mix plunger positions, said first and second sealing means being received in a first and a second groove in the filled position, said first sealing means being received in a third groove in the transfer position, and said first and second sealing means being received in the second and a fourth groove in the mix position, whereby the dental operator is simultaneously visually and tactilely advised of each of said plunger positions.