Abstract: A device is described for containing abrasive particles expelled from air-abrasive apparati and permitting their removal. One embodiment disclosed is a device for containing abrasive material expelled by a gas abrasive dental apparatus. The device comprises a collecting chamber in fluid communication with a containment chamber. Between the two is a transfer opening for permitting passage of abrasive particles between them. The device contains an inlet that fluidly connects to the nozzle of an air-abrasive apparatus, and an outlet to permit contact of abrasive particles with the surface to be treated. Excess abrasive particles are collected into the collecting chamber and transferred by vacuum or pressure to the containment chamber. The containment chamber contains a porous member which entraps the particles while permitting gas to flow freely out of the device. The disclosure includes several embodiments of the device depending on the particular application.