The regeneration of tooth in combination with homologous transplantation of freezed tooth germ and non-freezed bone marrow tissue.

在硬组织形成初期将未成熟的牙胚移植到牙槽内组织中的研究很少，尽管类似的研究是将这些组织移植到肾被膜或背部皮肤皮下组织中。首先，用光学显微镜观察冷冻牙胚的细胞形态和凝集素免疫组织化学，以探讨冷冻保存牙胚是否会对牙胚的各种细胞成分产生影响。同时对细胞间质中大量存在的复合多糖进行光镜观察。冷冻保存大鼠上第一磨牙牙胚生后5d，1周后解冻，并与未冷冻对照牙胚的成釉细胞、中间层细胞、星状细胞的组织学和表达情况进行比较，发现…的成釉细胞、中间层细胞、星状细胞牙釉质、成牙本质细胞、牙髓细胞和血管内皮细胞较多。随后，组织学、凝集素表达和复合多糖染色显示，实验组和对照组的大部分细胞和细胞间成分没有明显差异，表明冷冻保存对牙胚组织无明显影响。因此，出生后5天的牙胚从一半的同胞中取出，冷冻保存，并在出生后13天移植到其余同胞的颌骨中，术后1周和2周进行组织学观察。此外，糖链和复合多糖的染色也与未冷冻对照组进行了比较。术后1周散在可见新形成的凹陷，术后2周牙本质增厚。糖链和复合多糖在牙髓细胞和成牙本质细胞的表达和定位上与对照组无明显差异。以上结果表明，冷冻牙胚对牙本质的形成有促进作用。冷冻后的牙胚可见釉质吸收或骨性强直，两者均可发生在牙胚损伤中。这些变化的预防是有待解决的，今后结合牙胚移植和来自胫骨的骨髓组织植入形成了略厚的牙本质，尽管植入后残留的骨髓不能被证实，这些骨髓组织可能与改善牙本质的形成有关。较少

Very few researches were available on the transplantation of immature tooth germs at the initial stage of hard tissue formation into intraalveolar tissue, although similar studies on the transplantaion of those tissues into the capsule of kidney or the subcutaneous tissues of the back skin. Initially, cell morphology and lectin immunohistochemistry were examined in freezed tooth germ with light microscopy, to explore whether preservation of tooth germ by freezing could make any influence on various cellular components of tooth germ. Simultaneously, light microscopic staining of compound polysaccharides were carried out to observe these polysaccharides which exists abundantly at the intercellular tissue.The rat tooth germ of upper first molar was preserved by freezing at postnatal 5 day, thawed after one week, and histology and the expression of compound polysaccharides were compared with non-freezed control tooth germ on ameloblasts, cells of the intermediate layer, stellate cells of e … More namel pulp, odontoblasts, pulp cells and vascular endothelial cells. Subsequently, histology, lectin expression and staining of compound polysaccharides showed no definite difference in most of cellular and intercellular components between the experimental group and the control, suggesting that preservation by freezing made no significant changes in tooth germ tissue.Consequently, tooth germs at postnatal 5 days were taken from the half number of siblings, and preserved by freezing, and transplanted into the jaw bone of the remaining siblings at postnatal 13 days, and the capacity of transplanted tooth germ to form hard tissue was explored histologically at postoperative one and two weeks. Moreover staining of sugar chains and compound polysaccharides were also compared with the unfrozen control group. Newly formed dent inogenesis was scatteringly observed at postoperative one week, and the dentin became thick at postoperative 2 weeks. Sugar chains as well as compound polysaccharides showed no definite deviation in expression and localization of pulp cells and odontoblasts between the experimental and control group. These above findings suggested that frozen tooth germs maintained dentinogenesis. Resorption of enamel or osseous ankylosis, both of which could occur in the trauma of tooth germ, was observed in those frozen tooth germs. The prevention of these changes is open to be solved hereafter The combination of tooth germ transplantation with the implantation of bone marrow tissue from the tibia formed slightly thicker dentin, although the residual bone marrow could not be confirmed after the implantation and such marrow tissue could be associated with the improved dentinogenesis, if any. Less