مرکز منطقه ای اطلاع رساني علوم و فناوري -

چكيده لاتين :

The effect ofaddition ofNaHF] on the cement setting and the set mass has been studied as an initial step to determine how jluoride influences the characteristics of a calcium phosphate cement, consisting of tetracalcium phosphate [TTCP:Ca4(P04hOJ and dicalcium phosphate dihydrate [DCPD:CaHP04.2H]Oj. NaHF] [0-10% }iיt% ofpowder phaseJ has been dissolved in double distilled water and used as the liquid phase of the apatite cement (AC). Powder X-ray diffraction analysis and FTIR measurements revealed that fluoride was necessary in promoting the formation of the apatite phase. The setting time 11יQS decreased significantly by the addition ofNaHF2from 0% to 6%, but increased resulted in the AC(8-10%) . The set AC(2%) has the highest compressive strength and the lowest porosity. The dissolution rate of set AC in weak acid. pH 5.5, was decreased with the amount of added NaHF] from 0% to 6% but increased in the set AC 8-1O%. The formation of jluoroapatite in AC(6%) was provided the low solubility and good acid resistance which is necessary for dental application. SEM observation showed needle-like apatite crystal growth over particulate matrix surface, however the amount of non-reactive TTCP or DCPD particles decreased by the addition of NaHF2. The CalP ratio, which was determined by EDAX, increased significantly with the addition ofNaHF].