Maxillary sinus floor elevation with a tissue-engineered bone composite of deciduous tooth stem cells and calcium phosphate cement in goats.

The study aimed to assess the effect of maxillary sinus floor elevation with tissue-engineered bone constructed from deciduous tooth stem cells (DTSCs) and calcium phosphate cement (CPC). The stem cells from goat deciduous teeth (SGDs) were isolated and transfected by means of the adenovirus with an enhanced green fluorescent protein gene (AdEGFP). As many as 18 bilateral maxillary sinuses of nine goats were randomly allocated into three groups (n = 6/group): group A (SGDs-CPC compound), group B (CPC alone) and group C (autogenous bone obtained from an iliac crest). All the samples were evaluated by computed tomography (CT), histology and histomorphometric analysis. Furthermore, the fate of implanted SGDs was traced using an immunohistochemical staining method in the decalcified samples. SGDs might be differentiated into osteoblasts in an osteogenic medium. In the present study, three-dimensional CT analysis showed that the volume of newly formed bone in group A was greater than that in the other two groups. After a healing period of 3 months, sequential analyses of triad-colour fluorescence labelling, histology and histomorphology indicated that the SGDs-CPC compound primarily promoted bone formation and mineralization at 2 and 3 months after the operation. Moreover, the areas of new bone formation in elevated sinuses were 41.82 ± 6.24% in the SGDs-CPC group, which was significantly higher than the 30.11 ± 8.05% in the CPC-alone group or the 23.07 ± 10.21% in the autogenous bone group. Immunohistochemical staining revealed that GFP and OCN were both expressed in the new bone tissue for the samples with eGFP, which suggested that the implanted SGDs might have contributed to new bone formation on the elevated sinus floor. SGDs can promote new bone formation and maturation in the goat maxillary sinus, and the tissue-engineered bone composite of SGDs and CPC might be a potential substitute for existing maxillary sinus floor elevation methods. Copyright © 2014 John Wiley & Sons, Ltd.

[Preliminary study of akermanite's effect on stem cells from goat deciduous teeth in proliferation and osteogenic differentiation].

PURPOSE: To explore the characters of attachment, proliferation and osteogenic differentiation of stem cells from goat deciduous teeth (SGDs) cultured on akermanite ceramic. METHODS: SGDs were collected with enzyme digestion, and cultured. Under culture condition in growth medium, actin filament labeling and CCK-8 analysis were used to reveal attachment and proliferation. Expression level of alkaline phosphatase (ALP) and osteogenic differentiation genes (ALP, COL I, OPN and OCN) were examined by pNPP method and real-time PCR. The data was analyzed using SPSS 13.0 software package. RESULTS: Compared with ß-TCP, SGDs seeded on akermanite ceramic not only spread out better, but also grew faster since day 4. In osteogenic medium, cells of akermanite group had stronger ALP activity at day 4 and 7. The gene expression of akermanite was more than the ß-TCP group. The gene OCN expression level increased significantly at day 7 (P<0.01). CONCLUSIONS: SGDs can attach and grow well on akermanite ceramic. Compared with ß-TCP, akermanite ceramic shows an advantage in osteogenic differentiation of SGDs.

[Ectopic osteogenesis of SGDs in goat's muscle pouch].

PURPOSE: To investigate ectopic osteogenesis of composites SGDs with porous calcium phosphate cement(pCPC) in goat's muscle pouch. METHODS: SGDs were cultivated with modified tissue culture techniques, then were induced into osteoblasts in the third passage, the osteogenic-induced SGDs were combined with pCPC and transplanted into the goat left dorsal muscle pouch, the pCPC without cells was transplanted into the right dorsal muscle pouch as negative controls. The transplants were harvested at 2-,4-,6-,8- week and prepared for histological examination. The morphologic quantitative analysis was made by SPSS 16.0 software package. RESULTS: Bone formation was not detected in pCPC without cells by histological examination. 2,4,6,8 weeks after transplantation in SGDs-pCPC group, the percentages of bone formation were (1.24±0.25)%,(1.59±0.23)%,(4.12±0.39)% and (5.68±0.58)%,respectively.There was no significant difference in bone formation at 2 and 4 weeks after transplantation (P>0.05). At 8- week, the percentages of bone formation were higher than that at 6- week in SGDs-pCPC group, and both significantly higher than that at 2- and 4- week(P<0.05). CONCLUSION: SGDs combined with pCPC have the ability of ectopic osteogenesis.

[Experimental study on stem cells from goat deciduous teeth compounded with porous calcium phosphate cement for ectopic osteogenesis].

PURPOSE: To observe the biocompatibility and ectopic bone-like tissue formation of stem cells from goat deciduous teeth (SGDs) with porous calcium phosphate cement (pCPC). METHODS: The expression of STRO-1 on SGDs was measured with flow cytometry (FCM); the 4th passage SGDs were cultured in induced-mineralization medium in vitro for 7 days. Combined with pCPC, the adhesion and growth of the compounds were observed with scanning electron microscopy (SEM); the ectopic bone-like tissue formation was observed 8 weeks after the compounds implanted subcutaneously into the nude mice. RESULTS: On the third day of SGDs compounded with pCPC, SEM verified that the cells adhered closely and tightly with pCPC, protruded pseudopods and secreted matrix. 8 weeks after the compounds implanted in ectopic sites, HE staining confirmed the formation of bone-like tissue; Immunohistochemistry showed the strongly positive expression of OCN protein in the implanted materials. CONCLUSIONS: SGDs may differentiate into osteoblast and are potential to induce bone matrix formation; combined with pCPC, the compounds may generate bone-like tissue.