Materials and Methods: The 40 moloar teeth without alveolysis within one week, were tied with steel wire, treated with root cannel filling or resinifying therapy.
Unique straight or spiral grooved feed bush with force cooling system and unique screw ensure high plastification in low temperature, high speed extrusion of material.
The device comprises a mixing plastifying screw, a machine barrel, a screw driving system, a bracing frame and a bearing arranged on the bracing frame.
Vibration force field was introduced into processing of plastics in tri-screw dynamic mixing extruders,so as to intensifying mixability and dispersion.
After numerous failed attempts to make use of PVC, an American successfully plasticized it in the 1920's and began experimenting with it as a cheaper and more durable alternative to rubber and to other plastics.