Department of Oral and Maxillofacial Surgery/Plastic Surgery, School of Medicine, University of Jena, Germany.
Int J Oral Maxillofac Implants. 2011 Jul-Aug;26(4):760-7.
The structure of peri-implant soft tissue that is regenerated after flapless and flap surgery has been shown to differ. However, its underlying mechanisms are relatively unknown. The present study sought to identify differences in the inflammatory cell infiltration and expression of gene transcripts during transmucosal healing between the two approaches with two different implant designs.
All mandibular premolars were removed from 12 minipigs. One month later, four implants (two NobelReplace Tapered Groovy and two NobelPerfect Groovy, Nobel Biocare) were placed in each quadrant. One quadrant was randomized to flapless insertion, while the other was chosen for flap surgery in each animal. Following 1, 2, 4, and 12 weeks of transmucosal implant healing, biopsy specimens were retrieved from the peri-implant soft tissue according to a standardized procedure to avoid crossover effects. Samples were subjected to a leukocyte count and a gene expression analysis.
When the flapless placement technique was used, leukocyte influx in the peri-implant soft tissue was significantly smaller compared to open surgery for both implant designs. Gene expression analysis revealed significant overexpression of molecules associated with detoxification and reepithelialization in the flapless group. In contrast, myofibroblast-associated gene transcripts were significantly enriched in the flap surgery group.
The present data indicate perpetuation of inflammatory reactions as well as increased fibrotic scar tissue deposition in the peri-implant area following implant placement by the flap approach. Flapless implant insertion results in less inflammation and early reepithelialization, providing the potential for the formation of a fully functioning as well as esthetically preferable peri-implant soft tissue collar.
无瓣和有瓣手术后再生的种植体周围软组织结构已被证明存在差异。然而，其潜在机制尚不清楚。本研究旨在通过两种不同的种植体设计，确定两种方法在黏膜下愈合过程中炎症细胞浸润和基因转录表达的差异。
从 12 只小型猪中去除所有下颌前磨牙。一个月后，每个象限各植入 4 枚种植体（2 枚 NobelReplace 锥形凹槽种植体和 2 枚 NobelPerfect 锥形凹槽种植体，均来自 Nobel Biocare）。每个象限随机行无瓣植入，而每个动物的另一象限选择行有瓣手术。黏膜下种植体愈合后 1、2、4 和 12 周，根据标准化程序从种植体周围软组织中取出活检标本，以避免交叉效应。对样本进行白细胞计数和基因表达分析。
与开放式手术相比，无瓣放置技术可显著减少种植体周围软组织中的白细胞浸润，两种种植体设计均如此。基因表达分析显示，无瓣组中与解毒和再上皮化相关的分子显著过表达。相比之下，有瓣手术组中与肌成纤维细胞相关的基因转录物明显富集。
本研究数据表明，与无瓣种植体插入相比，有瓣种植体植入后，炎症反应持续存在，并在种植体周围区域导致更多的纤维瘢痕组织沉积。无瓣种植体插入导致炎症减少和早期再上皮化，为形成功能齐全且美观更优的种植体周围软组织领提供了可能。
