Yang Jian-zhen, Ouyang Yong, Liao Zhi-qing
Department of Preventive Dentistry, Sun Yat-sen University, Guangzhou, China.
Zhonghua Kou Qiang Yi Xue Za Zhi. 2011 Aug;46(8):489-93.
To observe the process of pulp revitalization of immature permanent teeth after pulpectomy.
Thirty-two single-rooted teeth with open apices from 4 Beagle dogs aged 4 months were included in the study. The pulpal tissues of 8 front teeth with single root of each dog were removed, and a blood clot was produced to the level of the cementoenamel junction followed by a double seal of mineral trioxide aggregate and composite resin. At day 7, 14, 21 and 28, respectively after operation, the dog was sacrificed, and then longitudinal paraffin sections were made for histologic investigation.
After 7 days, about one thirth of the pulp chamber had an ingrowth of new tissue. After 14, 21, 28 days, there were more and more new tissue in the chamber. This new tissue consisted of well-organized and well-vascularized connective tissue. Hard tissue was too observed in the root canal. In some cases, the newly generated hard tissue even deposited against the canal dentinal walls.
The pulp of immature permanent teeth can revitalize after removal of the original pulp tissue under suitable conditions.
观察年轻恒牙牙髓切断术后牙髓再生的过程。
选取4只4月龄的比格犬，共32颗单根且根尖孔开放的牙齿纳入研究。每只犬的8颗单根前牙去除牙髓组织，在牙骨质牙釉质界水平形成血凝块，然后用三氧化矿物凝聚体和复合树脂进行双层封闭。术后第7天、14天、21天和28天分别处死实验犬，制作纵行石蜡切片进行组织学观察。
术后7天，约三分之一的髓腔有新组织长入。术后14天、21天、28天，髓腔内新组织越来越多。这些新组织由排列有序、血管丰富的结缔组织组成。根管内也观察到硬组织。在某些情况下，新生成的硬组织甚至沉积在根管牙本质壁上。
年轻恒牙在合适的条件下，去除原有牙髓组织后牙髓可以再生。
