Surface modification of titanium (Ti) influences cell behavior, and immobilization of bone morphogenetic protein (BMP)-2 on a Ti surface cells to differentiate into osteogenic cells. This study aimed to evaluate the effect of an artificial fusion protein (AFP) comprising a modified BMP-2 and Ti-binding peptide (TBP) motif (AFP-TBP–BMP-2) on osteogenesis of rat abdominal cells on Ti surface in vivo. Ti plates were dipped in three different mixtures of collagen gel: collagen gel only, collagen gel with BMP-2, and collagen gel with AFP-TBP–BMP-2. The treated Ti plates were then implanted into rat abdominal muscles. One and 2 weeks after implantation, these plates were histologically observed. The Ti plate with collagen gel and AFP-TBP–BMP-2 produced cartilage in the muscle at 1 week, and bone-like hard tissue was observed at 2 weeks. These results suggest that the application of collagen gel with AFP-TBP–BMP-2 accelerates osteogenesis in vivo.

View full abstract

The salivary milieu should be considered when examining the biological effects of dental biomaterials. However, some human or artificial saliva components may be unsuitable for cell culture medium. The objective of the present study was to obtain basic data to develop a cell culture medium for a saliva model as an alternative to animal experiments, in order to facilitate the in vitro evaluation of dental biomaterials. Specifically, to examine whether cells can be cultured in tissue culture medium containing saliva factors, the recovery rates of two cell types were examined after the addition of human or artificial saliva to cell culture medium, demonstrating that human or artificial saliva should be diluted with tissue culture medium to about 50% or less.

View full abstract

Noble fibrous porous apatite disks have recently been produced. The purpose of this study was to evaluate the usefulness of porous apatite disks as osteo-conductive absorbable bio-material by using animal model. Critical-size bone defects were generated in the cranial bones of six Wistar rats, in which porous apatite disks (6 x 1 mm) were implanted. Micro-computed tomography (CT) revealed that mean opacity values of the cranial defect zones implanted with porous apatite disks significantly increased from 3 days to 4 weeks (p < 0.01); but was similar between at 4 weeks and at 8 weeks. After feeding for 8 weeks, the rats were sacrificed. Histological observations revealed that porous apatite disks implanted in rat cranial defect zones for 8 weeks were partially absorbed, while new bone was formed in and near the bio-absorbed regions. Taken together, it was considered that porous apatite disks could be employed as new osteo-conductive and slightly-absorbable bone substitute materials.

View full abstract

To collect basic data for determining cytotoxicity with a three-dimensional tissue model that simulates the living body, direct contact between the sample and cell layer through collagen was compared with collagen insertion between the sample and cell layer using six dental monomers (Bis-GMA, UDMA, Bis-MPEPP, D-2.6E, TEGDMA, and HEMA). Cytotoxicity levels were different for some monomers in the two tissue models, suggesting that the tissue model design influences cytotoxicity. Tissue models for preclinical studies on dental biomaterials will become more strongly desired. Thus, such models should be improved and established for the biological evaluation of dental biomaterials.

View full abstract

Strontium (Sr) ions are widely applied in bone regeneration therapy. However, it remains unclear whether Sr has the capacity for application in cartilage regeneration therapy using adipose-derived stem cells (ADSCs). Here, we demonstrate that the Sr ions contained in chondrogenic medium (CM) potently enhanced the chondrogenic differentiation of human ADSCs in vitro. Human ADSCs were isolated from the buccal fat pad of a middle-aged woman during oral surgery. ADSCs were then exposed to CM with or without Sr (0.15–15.00 mM) for up to 14 days. CM containing 1.50 mM Sr significantly increased the secretion of glycosaminoglycans (GAGs) and the mRNA expression of SRY(sex determining region Y)-box 9 and collagen type 2 alpha 1 compared with CM alone and basal medium. There were no obvious increases in adipogenic, osteoblastic, or hypertrophic chondrogenic differentiation markers. The results indicated that Sr was prospective agent to induce the chondrogenic differentiation of ADSCs.

View full abstract

Many novel microdevices in the space of a crown, pontic of a bridge, denture, or superstructure of the oral implant. We previously proposed the application of a microdevice for diabetes treatment by placing it in a prosthesis applied in the oral cavity. In this study, I propose its applicability to the nursing care field by developing a technique and many other ideas by adding a Global Positioning System (GPS) function.

View full abstract

Author's name correctionIn the published article"Evaluation of Bone Regeneration using Platelet-rich andPlatelet-poor Plasma Combined with Autologous Mesenchymal Stem Cells. J OralTissue Engin, 2013; 11(1): 57-66."the author's name is given incorrectly.The Editorial Office of J Oral Tissue Engin would like to correct the author's name.By mistake of the authors from the paper submission. Our editorial committee wasaccepted the offer of the correction of the author's name.Error: Li PEIQI → Correct: Peiqi LI

View full abstract