Maslamani Manal, Joseph Bobby, Gabato Severino, Andersson Lars
Department of Restorative Sciences, Faculty of Dentistry, Kuwait University, Kuwait, Kuwait.
Department of Diagnostic Sciences, Faculty of Dentistry, Kuwait University, Kuwait, Kuwait.
Dent Traumatol. 2018 Jun;34(3):182-187. doi: 10.1111/edt.12398. Epub 2018 Apr 26.
BACKGROUND/AIM: Delayed (dry storage > 60 minutes) replantation results in ankylosis and replacement resorption. It has been suggested to remove the non-viable periodontal ligament before replantation to possibly reduce the rate of replacement resorption. However there has been no study on the rate of replacement resorption after such measures. The aim of this study was to investigate if there was any difference in the rate of replacement resorption by either removing the periodontal ligament (PDL) with gauze or not removing PDL in teeth subjected to delayed replantation followed by healing for 2 or 6 weeks.
Maxillary central incisors were extracted in 8 rabbits. In the right central incisors, the necrotic PDL was removed by dry gauze over the root surface. In the left eight extracted teeth PDL was left on the root surface. All extracted teeth were left to dry for 60 minutes. Extra-oral root canal treatment was performed before replantation. The rabbits were sacrificed after 2 weeks and 6 weeks respectively. Histologic processing and evaluation was done.
In the 2 weeks group, all teeth showed ankylosis. The cementum was intact, and fusion of the bone and root was generally seen without resorption of the root, whereas in the 6 weeks group regardless of whether PDL had been kept or not, ankylosis and osseous replacement of the dentin was seen. There was no evidence of inflammatory infiltrate in the sections examined.
Removal of PDL prior to delayed replantation may result in some initial protection of the cementum during the first few weeks. However, over longer times there seems to be neither protection of the dentin from ankylosis and osseous replacement, nor any influence on the rate of replacement resorption.
背景/目的：延迟（干储存超过60分钟）再植会导致牙齿强直和替代性吸收。有人建议在再植前去除无活力的牙周膜，以可能降低替代性吸收的发生率。然而，尚未有关于采取此类措施后替代性吸收发生率的研究。本研究的目的是调查在延迟再植并愈合2周或6周的牙齿中，用纱布去除牙周膜（PDL）与不去除PDL的情况下，替代性吸收发生率是否存在差异。
在8只兔子身上拔除上颌中切牙。右侧中切牙，用干纱布在牙根表面去除坏死的PDL。左侧8颗拔除的牙齿，PDL留在牙根表面。所有拔除的牙齿均晾干60分钟。再植前进行口外根管治疗。兔子分别在2周和6周后处死。进行组织学处理和评估。
在2周组中，所有牙齿均表现为强直。牙骨质完整，通常可见骨与牙根融合，牙根无吸收，而在6周组中，无论PDL是否保留，均可见牙齿强直和牙本质的骨质替代。在所检查的切片中没有炎症浸润的证据。
延迟再植前去除PDL可能在最初几周对牙骨质起到一定的保护作用。然而，从更长时间来看，似乎既不能保护牙本质免于强直和骨质替代，也对替代性吸收的发生率没有任何影响。
