碱性成纤维细胞生长因子在牙发育各阶段中的表达及意义

Expression of basic fibroblast growth factor in each stage of tooth development and significance

目的：观察碱性成纤维细胞生长因子（bFGF）在牙发育各阶段中的表达,探讨其作用及意义。方法：以胎龄834周人胎儿牙胚、出生122 d乳鼠和出生6周5个月犬牙为研究对象,采用免疫组织化学法定性观察bFGF发育各阶段的表达强度。结果：bFGF在牙发育的各个阶段均有表达。胎儿蕾状期和帽状牙蕾上皮、牙板、成釉器、内外釉上皮bFGF呈阳性表达,钟状期内釉细胞、中间层、成釉细胞、成牙本质细胞呈强阳性,牙乳头及牙囊bFGF呈阳性表达。乳牙萌出前、萌出期的生后乳鼠和生后6周犬牙,成釉细胞、成牙本质细胞、上皮根鞘、牙囊bFGF呈强阳性。犬恒乳牙替换期牙根、牙周膜及靠近牙周膜的成骨细胞bFGF呈阳性表达。结论：bFGF是牙发育的重要调控因子,参与牙胚细胞分化和形态发生、萌出及恒乳牙替换各阶段的调控。

Objective To observe the expression of basic fibroblast growth factor（bFGF） at different stages of tooth germ development,and explore its mechanism and significance.Methods Immunohistochemical technique was used to examine the expressions of bFGF in the tooth germs at different stages of human fetus in 8-34 weeks,the suckling mice with 1-22 d,and the dog postnatal in 6 weeks-5 months.Results bFGF expressed in tooth germ at all stages.In human fetus,the positive reaction was observed in epithelium of tooth bud,dental plate,enamel organ,external and outer enamel.The ameloblasts,odontoblasts,epithelial root sheath and dental follicle showed strongly positive reaction in the unerupted human deciduous tooth,the tooth under the eruption of neonate external enamel,stratum intermedium cells,ameloblasts and odontoblasts showed strongly positive epithelium,dental papilla and dental follicle at bud stage and cap stage,while at bell stage cells in mice and 6 week postnatal canal tooth.The positive expressions of bFGF were observed in root of tooth,peridental ligament and the osteoblasts adjoin to peridental ligament in the dog succession of decideous teeth.Conclusion bFGF is one of critical regulator in the tooth development,which can regulate the differentiation and morphogenesis of tooth germ cells and control the eruption and succession of deciduous teeth at different stages.