Receptor activator of NF-κB ligand (RANKL)/ Receptor activator of NF-κB (RANK) engaged activation of p38 Mitogen-activated protein kinase (p38), extracellular signal-regulated kinase (ERK1/2) on an osteoclast precursor cells. Phosphatidylinositol 3-kinase (PI 3-K) is critical to activation of cellular functions, which is activation of cell viability. However, It is not clarified about the relation of these kinase in the cascade of soluble RANKL (sRANKL) differentiation signaling. We investigated the role of PI 3-K on RANKL-mediated mouse leukemic monocyte cell line RAW264 cells differentiation into osteoclast cells. LY294002 blocked the differentiation into osteoclast cells induced by sRANKL in a dose dependent manner. Western analysis has shown that the posphorylation of p38 and ERK1/2 were blocked by LY294002 in a dose dependent manner. These results suggest that RANKL/RANK mediated phosphorylation of p38 and ERK1/2 and a differentiation into osteoclast cells depend on PI 3-K.
We previously reported that we analyzed the trace elements of crystal included in the powder of Mineral Trioxide Aggregate (MTA) by a SEM EDS. Ca, P, S, Mg, Si and Al were detected in the powder of MTA. Si and Al were substituted Ca and P with the maturation of root formation and were important element for the mineralization. These elemental resemble the trace elements which appear at the time of mineralization mechanism of like-predentin. On the manipulation of primary molar pulpotomy, the Formocresol (FC) fixation, the iodine calcium pharmaceutical (Vitapex), and the calcium hydroxide preparation are used usually, but the prognosis cannot necessarily be said to be a success. As direct pulp capping materials after vital pulpotomy, we experimented dogs dental pulp and influence to periapical tissue in MTA having dentin mineralization element. MTA formed cement-like calcification in dog animal experiment in 6 weeks and was present in the state that underneath of dental pulp was approximately normal. In addition, MTA exists among in pulp tissue for 8 weeks in the experiment. Some only pulp hyperemia was observed, and there was not the inflammatory spread and here was not influence to periapical tissue in both groups. On the pulpotomy by calcium hydroxide, the dentin-bridge was formed, but the vacuolar degeneration and the inflammatory cells observed partly in the pulp at the underneath of dentin-bridge, here was not influence to periapical tissue in both groups. From these results, it was suggested that MTA component regulated the vital reaction, and was the useful composition on the treatment of vital pulpotomy.
On the maxillary sinus floor augmentation (the maxillary sinus lift) of the basal bone with 1 to 2mm height and poor bone volume, it may not be securable the efficient regenerated bone for poor blood flow from the sinus mucosa membrane and the bed bone, even if applying crushed autogenously bone. In the range that we could perform as a clinician, the operation of maxillary sinus lift, using three elements of APC-PRP (Auto Platelet concentration Platelet Rich Plasma) as the growth factor, the mixing CHA (carbonate apatite) and the crushed autogenously bone as scaffold, and the somatic stem cell from the ileum which were based on the doctrine of tissue engineering.On 4 months later, when we inserted in the oral implant, an internal diameter used hollow drill of 2 or 3mm, and D2 degree was able to obtain the augmented neonatal bone with the form of block.We performed the histomorphometry examination using the blocked bone.In part |5 that required the most bone augmentation, the ripening ossification rate was 40.15%, the neogenesis ossification rate was 6.40%, and the bone occupancy was 46.75% or more on the mineralization.In bone marrow equivalency region, there is little vascular system between some remained CHA and the bone.The some part of CHA absorbed by the osteoclast-like cell and the osteoblast-like alpha cell were arranged in an orderly manner at the circumference.It passes after setting superstructure of implant in 15 months, and then the prognosis is good. From the above mentioned, We considered about the collagen type 1, the intercalary potential of Ca2+, CO32-, PO43- as the crystal formation, the adjustment of pH by CHA, and the control of bone revelation protein.