Abstract: A nozzle for a dental handpiece having a connector portion to be connected to a handpiece body, and a nozzle body, which is provided near its end with a notch of a substantially rectangular section cut out from the front face into the lateral faces, the notch forming upstream and downstream faces. The nozzle has a channel and an injection port thereof for transferring the mixture and a channel and an injection port thereof for transferring water, separate from each other. The channel for the mixture extends through the nozzle body along the front face from the connector portion to near the end, with the injection port for the mixture opened in the upstream face. With this nozzle, the mixture is properly injected onto a treatment site in subgingival treatment, while the mixture injected subgingivally is efficiently discharged supragingivally, to improve work efficiency in dental treatment.

Abstract: The dental handpiece has a handpiece body having a mixture transfer line for transferring a mixture of air and powder, and a nozzle connected to the handpiece body for injecting the mixture transferred through the mixture transfer line, and performs dental treatment by injecting the mixture onto tooth surface. The nozzle is rotatably connected to the handpiece body via rotary means. With this nozzle connection, during subgingival treatment with the nozzle being inserted subgingivally at its end and moved along the tooth surface, the entire handpiece body is not required to be moved from side to side over a wide amplitude, which improves work efficiency in dental treatment.

Abstract: A nozzle for a dental handpiece is composed of a connector portion to be connected to a handpiece body, and a nozzle body, which is provided near its end with a notch of a substantially rectangular section cut out from the front face into the lateral faces, the notch forming upstream and downstream faces. The nozzle has a channel and an injection port thereof for transferring the mixture and a channel and an injection port thereof for transferring water, separate from each other. The channel for the mixture extends through the nozzle body along the front face from the connector portion to near the end, with said injection port for the mixture opened in the upstream face. The downstream face is provided with a guide for receiving the mixture injected through the injection port for the mixture and guiding the injected mixture outside the notch.

Abstract: A spherical cellulose material wherein the cellulose material is a water-insoluble polysaccharide formed by ?-1,4-type sugar chain linkages, the degree of crystallinity is 70% or greater, and macrofibrils are formed radially from the center to the periphery.

Abstract: A cellulose dope comprising an aqueous sodium hydroxide solution and cellulose dissolved in the solution, wherein the cellulose dope has a sodium hydroxide concentration (CNa) of from 6.5 to 11% by weight, a cellulose content (Cc) of from 5 to 10% by weight, a viscosity average degree of polymerization (DPc) of the cellulose of from 350 to 1,200 and a cellulose dissolution ratio (Sc) of 99.0% by weight or more, and wherein the zero-shear viscosity (?0) and the cellulose content (Cc) of the cellulose dope and the viscosity average degree of polymerization (DPc) of the cellulose in the cellulose dope satisfy the following formula (1): ?0=kCcm×DPcp ??(1) wherein: ?0 represents the zero-shear viscosity (mPa·s) of the cellulose dope, Cc represents the cellulose content (% by weight) of the cellulose dope, DPc represents the viscosity average degree of polymerization of the cellulose in the cellulose dope, k=3.9×10?11, m is a number of from 5 to 7, and p is a number of from 3 to 4.

Abstract: A spherical cellulose material wherein the cellulose material is a water-insoluble polysaccharide formed by &bgr;-1,4-type sugar chain linkages, the degree of crystallinity is 70% or greater, and macrofibrils are formed radially from the center to the periphery.

Abstract: A method for producing a cellulose shaped article characterized by causing cellulose dope substantially composed of an alkali soluble cellulose and an aqueous alkali solution having an alkali concentration of 5 to 15% by weight to coagulate in an aqueous acidic solution having a temperature of at least the freezing temperature and less than 20.degree. C., then drawing the resultant solid 1.05 fold to less than 2.0 fold, then performing heat treatment. It is possible to provide a process free from the generation of waste gas and the danger of explosion during the molding process and also free from environmental pollution and it is possible to provide a cellulose shaped article having mechanical properties of the same extent of existing cellulose shaped articles in terms of physical properties.