Vitapex诱导年轻恒牙根尖形成的机制初探

Initial study on the mechanism of apexification of young permanent teeth with Vitapex

目的观察Vitapex诱导年轻恒牙根尖形成后根尖硬组织的组成,探讨根尖形成可能的机制,以指导临床上合理选择诱导剂。方法用未成年家犬制作牙髓炎、尖周炎模型,再用Vitapex行根尖诱导术,分别于术后4周、8周处死实验犬,作组织切片,观察根尖部硬组织组成,分析其可能的来源,探讨根尖形成可能的机制。结果牙髓炎组术后4周根尖有骨样牙本质、骨样牙骨质生成,术后8周牙根趋于封闭;尖周炎组术后4周牙根无延长,根尖炎细胞浸润,术后8周根尖有疏松的骨样硬组织生成。结论通过诱导剂的消毒作用可恢复根尖牙髓或牙乳头活性,从而使牙根继续发育,若根尖牙髓、牙乳头活性丧失,可用氢氧化钙制剂诱导根尖骨组织再生。

Objective The authors observed the comprise of root apical hard tissue after apexification of immature permanent teeth with Vitapex,and studied the mechanism of apexification. Then choosing inducer for root apex formation could be more reasonable in clinics. Methods The authors made the models of pulpitis and periapical periodontitis on young dogs with immature teeth, and in- duced root apex formation with Vitapex. The dogs were sacrificed 4 weeks and 8 weeks later respectively. The sections were made. Ob- serve the formation of root apical hard tissue, analyze its possible origin and discuss the possible mechanism of root apex formation. Re- suits In the pulpitis group, there were hard tissures as osteoid-dentin and osteoid-comentum deposited on the apices 4 weeks later, and the root apices formed 8 weeks later. In the periapical periodontitis group, there were inflamation on the apices 4 weeks later, and there were a little of loose har.d tissures as osteoid-dentin and osteoid-comentum deposited on the apices 8 weeks later. Conclusions The root pulp and the dental papilla could be saved by using apexification paste to prevent infection. In this way ,the root continue to form. How- ever,when the root pulp and the dental papilla couldn＇t he saved, calcium hydroxide apexifieation techniques could be used to induce calcifying on the apices.