de Gregorio Cesar, Cohenca Nestor, Romano Fabio, Pucinelli Carolina M, Cohenca Nathalie, Romero Martin, Lucisano Marilia P, Assed Bezerra da Silva Raquel, Assed Bezerra da Silva Lea
Department of Dentistry, University Rey Juan Carlos, Madrid, Spain.
Department of Pediatric Dentistry, University of Washington and Seattle Childrens Hospital. Private practice limited to endodontics in Seattle, WA.
Dent Traumatol. 2018 Oct;34(5):336-346. doi: 10.1111/edt.12427.
BACKGROUND/AIM: The extra-alveolar dry period and storage medium in which a tooth is kept prior to replantation remain critical factors affecting the survival and repair potential of the periodontal ligament in avulsed teeth. When replantation is not immediate, replacement root resorption (RRR) is the most common complication. The aim of this histological study was to evaluate the effect of immediate controlled-orthodontic forces in periodontal healing of replanted teeth in a canine model.
Sixty maxillary and mandibular premolar roots were endodontically treated in vivo and subsequently hemisected and extracted. Roots were replanted after an extraoral dry time of 20 minutes and randomly assigned to two experimental groups: Group 1: root was stabilized with a flexible and passive bracket/stainless steel wire splint for 2 weeks; Group 2: root was stabilized with a flexible bracket/NiTi wire splint activated with orthodontic elastics for 2 weeks. After 4 months, the dogs were euthanized, and all specimens were processed for histology and microscopically evaluated.
The mean percentage of RRR for Group 2 was 3.17 compared with 12.13 in Group 1. Eighty-three percent of specimens from Group 2 exhibited similar healing to the negative control group, compared to 60.5% of the specimens from Group 1. No statistical difference was found in periodontal healing between experimental groups.
Immediate application of mild and controlled orthodontic forces was not detrimental to the periodontal healing of teeth replanted after 20 minutes extraoral dry time, although no significant improvement on periodontal healing was observed.
背景/目的：牙槽外干燥期以及牙齿再植前保存牙齿的储存介质仍然是影响脱位牙牙周膜存活和修复潜力的关键因素。当不能立即进行再植时，替代性牙根吸收（RRR）是最常见的并发症。本组织学研究的目的是评估在犬模型中立即施加可控正畸力对再植牙牙周愈合的影响。
60颗上颌和下颌前磨牙牙根在体内进行根管治疗，随后进行半切并拔除。在口外干燥20分钟后将牙根再植，并随机分为两个实验组：第1组：用柔性被动托槽/不锈钢丝夹板固定牙根2周；第2组：用柔性托槽/镍钛丝夹板并通过正畸弹力圈激活固定牙根2周。4个月后，对犬实施安乐死，并对所有标本进行组织学处理和显微镜评估。
第2组RRR的平均百分比为3.17，而第1组为12.13。第2组83%的标本显示出与阴性对照组相似的愈合情况，而第1组为60.5%。实验组之间在牙周愈合方面未发现统计学差异。
在口外干燥20分钟后再植牙齿时，立即施加轻度可控正畸力对牙周愈合无害，尽管未观察到牙周愈合有明显改善。
