Abstract: A dental syringe may include a replaceable valve cartridge containing one or more valves. The valves may include air and water valves using a seating surface and an opposing seating surface with a relative angle formed between the two surfaces. The relative angle allows for regulation of the flow of fluid traveling through the valves. The replaceable valve cartridge may also include a system to remove a residual liquid from a tip of a dental syringe. Additionally, the replaceable valve cartridge may include a seal that prevents bleed-over of fluids within a dental syringe through use of first and second rings of elastic portions of the seal with a low pressure zone defined in between. Further, the dental syringe may include a tip retention insert which may be replaceable and may use either a pair of plates or a plurality of ball bearings to retain the dental syringe tips.

Abstract: A dental syringe may include a replaceable valve cartridge containing one or more valves. The valves may include air and water valves using a seating surface and an opposing seating surface with a relative angle formed between the two surfaces. The relative angle allows for regulation of the flow of fluid traveling through the valves. The replaceable valve cartridge may also include a system to remove a residual liquid from a tip of a dental syringe. Additionally, the replaceable valve cartridge may include a seal that prevents bleed-over of fluids within a dental syringe through use of first and second rings of elastic portions of the seal with a low pressure zone defined in between. Further, the dental syringe may include a tip retention insert which may be replaceable and may use either a pair of plates or a plurality of ball bearings to retain the dental syringe tips.

Abstract: Embodiments of the present invention are related to tension adjustment for a tension spring in a flex arm. Example embodiments include a tension adjustment mechanism comprising a handle, a collar, and an adjustment nut. The adjustment nut is centrally threaded and engages with a threaded shaft. The adjustment nut is positioned between the collar and the tension spring of the flex arm. The collar surrounds the shaft and comprises at least one pin that protrudes toward the adjustment nut. The adjustment nut comprises a plurality of radial slots each separately configured to receive a pin. The handle is connected to the collar and configured to rotate the collar to displace the adjustment nut along the shaft. The handle may be further configured to disengage the pin with a radial slot, rotate to align the pin with a different radial slot, and engage the pin with the newly aligned radial slot.

Abstract: A dental syringe may include a replaceable valve cartridge containing one or more valves. The valves may include air and water valves using a seating surface and an opposing seating surface with a relative angle formed between the two surfaces. The relative angle allows for regulation of the flow of fluid traveling through the valves. The replaceable valve cartridge may also include a system to remove a residual liquid from a tip of a dental syringe. Additionally, the replaceable valve cartridge may include a seal that prevents bleed-over of fluids within a dental syringe through use of first and second rings of elastic portions of the seal with a low pressure zone defined in between. Further, the dental syringe may comprise a tip retention insert which may be replaceable and may use either a pair of plates or a plurality of ball bearings to retain the dental syringe tips.