OBJECTIVE:To study sterility test after using Non-PVC bivalve soft-bag injection in PIVAS. METHODS:The test was divided into 3 groups according to the type of transfusion solution packaging and dispensing environment. Group 1 received Glucose solution using bivalve soft-bag,dispensed in PIVAS;group 2 received Glucose solution using bivalve soft-bag,dispensed in wards area;group 3 received Glucose solution using plastic bottle,dispensed in wards area. After puncturing 1,3,6,9 times (n=80),finished products placed in ward for 0,2,4,6 h(n=20),and then sterility test was conducted with membrane filtra-tion method stated in second part of Chinese Pharmacopoeia (2010 edition). Infusion contamination of 3 groups was analyzed at 9th puncture. RESULTS:The growth of bacteria was not found in group 1;the positive detection rate of group 2 and 3 were 2.5%and 3.8%(n=320). The total positive detection rates after puncturing 1,3,6,9 times were 0,0.4%,0.4%,7.5%(n=240);the positive detection rates of group 1 were all 0,those of group 2 were 0,1.25%,0,8.75%and those of group 3 were 0,0,1.25%, 13.75%(n=80). After 9 times of puncture,the positive detection rates of group 1 after placing 0,2,4,6 h were all 0,those of group 2 were 25%,5%,0,5%;those of group 3 were 5%,15%,5%,30%(n=20). CONCLUSIONS:The use of the Non-PVC bi-valve soft-bag injection in PIVAS can effectively prevent microbial contamination.

Defects in oral hard tissue caused by various factors have a negative impact on the functional and aesthetic results of prosthetic treatment. In recent years, the usage of bone tissue engineering for bone reconstruction has drawn widespread attention. Bone tissue engineering exhibits significant advantages, including the abundance of building materials and few side effects. In this paper, the composition and structure of dentin and its application in bone tissue engineering are reviewed, providing a new way to further optimize its performance. The results of a literature review show that the structure of dentin is very similar to that of autogenous bone. The inorganic component is mainly hydroxyapatite (HA), while the organic component is mainly collagen I, noncollagenous proteins (NCPs) and growth factors. Because of its unique composition, dentin can act as a scaffold and/or growth factor source through different processing methods. The deproteinization process removes most of the organic substances and creates a HA-based scaffold material with high porosity, which allows for vascularization and cellular infiltration. Demineralization increases dentin porosity by reducing the crystallinity of the mineralized components, so that part of HA, collagen fibers and growth factors are preserved. Demineralized dentin possesses various regulation functions ranging from differentiation, adhesion and proliferation of primitive cells and bone forming cell lineage. Extracted NCPs, as bioactive molecules, have been proved to play important roles that control cell differentiation, crystal nucleation and mineralization in bone formation. NCPs could be combined with variety of scaffold materials and modify their properties.