OBJECTIVETo prepare dental ulcer powder by using particle design technology, and compare the effect on the micromeritic property of dental ulcer powder with regular grinding and ultrafine grinding methods.

METHODAbove three methods were respectively used to make dental ulcer powder, in order to evaluate their difference in appearance character, grain size distribution, specific surface area and porosity, contact angle, micro-morphological character and borneol's stability.

RESULTCompared with normal powder, ultrafine powder and particle design showed increase in color uniformity and decrease in sour taste, and the particle design powder smells almost no borneol. Their grain size distributions were significantly less that of normal powder (P < 0.01), with the same grain size distribution in ultrafine powder and particle design powder. Their specific surface areas and porosities were significantly more than that of normal powder (P < 0.01), with the highest figures in ultrafine powder. Their contact angles were significantly more than that of normal powder (P < 0.01), with the highest figure in particle design powder. The surface of normal powder was smooth, with a few of small particle adhered. The surface of ultrafine powder was partially coated with small particles, where as the surface of particle design powder was mostly coated with particles. There was difference in micro-morphological character and surface attachment among the three. The 10-day accelerate stability experiment showed that normal power, ultrafine powder and particle design powder lost borneol by 90. 13% , 66. 48% and 40.57%, respectively. Particle design powder showed the highest stability, followed by ultrafine powder and normal powder.

CONCLUSIONThe preparation process can affect the micromeritic properties, by changing microscopic structure of the powders. We can design the macroscopic property of powder by regulating the formation of the microscopic structure with particle design technology.