The Evaluation Of Biological Safety Of Room Curing Polymethyl Methacrylate Material Added With An Nano-inorganic Antibacterial Agents Loaded Silver

Owing to the cheap price、simple operation、rapidly curing, Roomtemperature curing polymethyl methacrylate (polymethylmethacrylate,PMMA) is widely used in clinica. Nano silver can resist a variety of oralbacteria, add nano inorganic antibacterial agent carrying silver to the oralmaterial to improve its antibacterial properties is a hotspot of currentresearch,which can effectively reduce the probability of tooth decay anddenture stomatitis and other oral diseases occurrence.Our studies haveproved that the room temperature curing PMMA material added withantibacterial agents have wonderful antimicrobial ability of oral commonpathogens， and antibacterial effect will last for a long time. But there isno clear conclusion for the biological effect of nanometer materials,therefore testing the biological safety of room temperature curing PMMAmaterials containing nanometer antibacterial agent is required.Biological materials should have good histocompatibility biologicalsafety and functional, to ensure its clinical application safely andeffective. Both genetic toxicity test and in vitro cytotoxicity test areimportant biological safety test index. Genetic toxicity test is used toevaluate material teratogenic carcinogenic mutagenic ability, in order to understand the long time effect of the material. In vitro cytotoxicity testcan quickly detect the toxicity or material’s diffusion. and the resultsrelated to the toxic effects of material in the body. The purpose of theabove toxicity test is to evaluate the biological safety of the material, inorder to confirm the lecel of the non-toxic.This experiment selected room temperature curing PMMA materialscontaining2wt%nanometer antibacterial agent，using micronucleus testand MTT to test the genetic toxicity and cell toxicity of it.Micronucleiexperimental obtained micronucleus rate of3.2‰, which is in accordancewith national standards. Every solution group of the subject showed nodose-response relationship.It preliminary confirmed that the subject hasno genetic toxicity. MTT experiment obtained the cell toxicity result was0grade. The cell membrane damage and abnormal nuclei are not foundedunder the microscope. It is assumed that the subject without cytotoxicity.Based on the above two experiments results, we can conclude that thematerial has good biological safety.