There is no pulp necrosis or calcific metamorphosis of pulp induced by orthodontic treatment: biological basis

ABSTRACT To biologically explain why the orthodontic treatment does not induce pulp necrosis and calcific metamorphosis of the pulp, this paper presents explanations based on pulp physiology, microscopy and pathology, and especially the cell and tissue phenomena that characterize the induced tooth movement. The final reflections are as follows: 1) the orthodontic movement does not induce pulp necrosis or calcific metamorphosis of the pulp; 2) there is no literature or experimental and clinical models to demonstrate or minimally evidence pulp alterations induced by orthodontic movement; 3) when pulp necrosis or calcific metamorphosis of the pulp is diagnosed during orthodontic treatment or soon after removal of orthodontic appliances, its etiology should be assigned to concussion dental trauma, rather than to orthodontic treatment; 4) the two pulp disorders that cause tooth discoloration in apparently healthy teeth are the aseptic pulp necrosis and calcific metamorphosis of the pulp, both only induced by dental trauma; 5) the concussion dental trauma still requires many clinical and laboratory studies with pertinent experimental models, to increasingly explain its effects on the periodontal and pulp tissues.

摘要
为从生物学层面阐释正畸治疗为何不会引发牙髓坏死及牙髓钙化变性，本文基于牙髓生理学、显微学及病理学视角，尤其结合正畸牙移动所特有的细胞与组织学现象，给出相关阐释。最终结论如下：
1. 正畸牙移动不会引发牙髓坏死或牙髓钙化变性；
2. 目前尚无文献或实验、临床模型能够证实，甚至仅能初步佐证正畸牙移动可诱导牙髓发生改变；
3. 若在正畸治疗期间或正畸矫治器拆除后不久被诊断为牙髓坏死或牙髓钙化变性，其病因应归因为牙震荡，而非正畸治疗；
4. 在外观健康的牙齿中，引发牙齿变色的两种牙髓病症为无菌性牙髓坏死与牙髓钙化变性，二者均仅由牙外伤诱发；
5. 牙震荡仍需开展更多结合相关实验模型的临床与实验室研究，以进一步阐释其对牙周组织及牙髓组织的影响。