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

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.