Bertl Kristina, Neuner Hemma, Meran Antonia, Bertl Michael H, Reich Ilse, Nemec Michael, Bruckmann Corinna, Stavropoulos Andreas, Bantleon Hans-Peter
Department of Periodontology, Faculty of Odontology, University of Malmö, Malmö, Sweden.
Division of Oral Surgery, University Clinic of Dentistry, Medical University of Vienna, Vienna, Austria.
J Periodontol. 2020 May;91(5):572-581. doi: 10.1002/JPER.19-0376. Epub 2019 Oct 17.
Gingival clefts (GCs) develop frequently during orthodontic space closure and may compromise the treatment outcome. This study assessed whether the time-point of orthodontic space closure initiation, after permanent tooth extraction, affects the incidence of GC.
In 25 patients requiring bilateral premolar extraction because of orthodontic reasons, one premolar, chosen at random, was extracted 8 weeks before space closure initiation ("delayed movement," DM), whereas the contralateral premolar was extracted 1 week before ("early movement," EM) ("treatment group"). Presence or absence of GC after 3 and 6 months ("time-point") was recorded and any association with various parameters (i.e., treatment group, time-point, gender, jaw, craniofacial growth, gingival biotype, buccal bone dehiscence after extraction, space closure) was statistically assessed.
Twenty-one patients contributing with 26 jaws were finally included in the analysis. Overall, GCs were frequent after 3 (DM: 53.9%; EM: 69.2%) and 6 months (DM: 76.9%; EM: 88.5%). EM (P = 0.014) and larger space closure within the study period (P = 0.001) resulted in a significantly higher incidence of GC. Further, there was a tendency for GC development in the presence of buccal bone dehiscence (P = 0.052) and thin gingival biotype (P = 0.054). "Fast movers" (herein cases with a tooth movement ≥1 mm per month) developed a GC in >90% of the cases already after 3 months. "Slow movers" developed a GC in 25% and 70% after 3 months and final evaluation, respectively.
GC development is a frequent finding during orthodontic space closure and seems to occur more frequently with early tooth movement initiation and in "fast movers."
牙龈裂（GCs）在正畸间隙关闭过程中经常出现，可能会影响治疗效果。本研究评估了恒牙拔除后正畸间隙关闭开始的时间点是否会影响GC的发生率。
在25例因正畸原因需要双侧拔除前磨牙的患者中，随机选择一颗前磨牙在间隙关闭开始前8周拔除（“延迟移动”，DM），而对侧前磨牙在间隙关闭开始前1周拔除（“早期移动”，EM）（“治疗组”）。记录3个月和6个月后（“时间点”）GC的有无，并对其与各种参数（即治疗组、时间点、性别、颌骨、颅面生长、牙龈生物型、拔牙后颊侧骨缺损、间隙关闭）的任何关联进行统计学评估。
最终纳入分析的有21例患者，共26侧颌骨。总体而言，3个月后（DM：53.9%；EM：69.2%）和6个月后（DM：76.9%；EM：88.5%）GC很常见。EM（P = 0.014）和研究期间更大的间隙关闭量（P = 0.001）导致GC的发生率显著更高。此外，在存在颊侧骨缺损（P = 0.052）和薄牙龈生物型（P = 0.054）时，有GC发生的趋势。“快速移动者”（此处指牙齿每月移动≥1 mm的病例）在3个月后>90%的病例中出现了GC。“慢速移动者”在3个月和最终评估后分别有25%和70%出现了GC。
GC的发生是正畸间隙关闭过程中的常见现象，似乎在早期牙齿移动开始时和“快速移动者”中更频繁出现。
