Hourfar Jan, Bister Dirk, Lisson Jörg A, Ludwig Björn
Department of Orthodontics, University of Heidelberg, Heidelberg, Germany.
Department of Orthodontics, Guy's and St Thomas' NHS Foundation Trust and King's College Dental Institute, London, UK.
Head Face Med. 2017 Jan 6;13(1):1. doi: 10.1186/s13005-016-0134-9.
The aim of this retrospective investigation was to evaluate the incidence of loss to pulp sensibility testing (PST) of maxillary front teeth after paramedian (3 to 5 mm away from the suture) orthodontic mini-implant (OMI) insertion in the anterior palate.
A total of 284 patients (102 males, 182 females; mean age was 14.4 years (±8.8) years at time of OMI-Insertion) with a total of 568 OMIs (1.7 mm diameter, length 8 mm) were retrospectively investigated. A binomial regression analysis was performed to explore covariates, such as age, gender, inclination of upper central incisors, dentition status and insertion position of OMIs that could have contributed to loss of sensibility. Statistical significance was set at p < 0.05.
Loss of response to PST was encountered during retention in 3 out of 284 patients and the respective OMIs had been placed at height of the second rugae (R-2). Affected teeth were a right canine, a left lateral and a left central incisor. Subsequent root canal treatment was successful. Results of the binomial regression analysis revealed that the covariate insertion position (R-2) of OMIs (p = 0.008) had statistically significant influence on loss of response to PST.
(1) Although there was no radiographic evidence for direct root injury, the proximity of the implants to the anterior teeth was nevertheless statistically related to loss of PST. (2) In all cases of PST loss OMIs were inserted at the second rugae. Therefore OMIs should be placed either more posteriorly, at the third rugae or in the median plane. (3). Loss of PST was not increased for patients with palatal OMI (0.18%) compared to samples without OMI (0.25%).
本回顾性研究旨在评估在前腭部正中旁（距缝线3至5毫米）植入正畸微型种植体（OMI）后上颌前牙牙髓敏感性测试（PST）丧失的发生率。
对284例患者（102例男性，182例女性；OMI植入时平均年龄为14.4岁（±8.8岁））进行回顾性研究，共植入568枚OMI（直径1.7毫米，长度8毫米）。进行二项式回归分析以探索可能导致敏感性丧失的协变量，如年龄、性别、上颌中切牙倾斜度、牙列状况和OMI的植入位置。设定统计学显著性为p < 0.05。
在284例患者中的3例保留期间出现PST反应丧失，相应的OMI植入于第二皱襞（R-2）高度处。受影响的牙齿为一颗右上尖牙、一颗左上侧切牙和一颗左上中切牙。随后的根管治疗成功。二项式回归分析结果显示，OMI的协变量植入位置（R-2）（p = 0.008）对PST反应丧失有统计学显著影响。
（1）尽管没有影像学证据表明存在直接的牙根损伤，但种植体与前牙的接近程度在统计学上与PST丧失有关。（2）在所有PST丧失的病例中，OMI均植入于第二皱襞处。因此，OMI应放置在更靠后的位置，即第三皱襞处或正中平面。（3）与未植入OMI的样本（0.25%）相比，腭部植入OMI的患者PST丧失并未增加（0.18%）。
