BACKGROUND This study compared the progression of experimental peri-implantitis between alveolar ridge preservation (ARP) and spontaneous healing (SH) sites in infected (IT) and noninfected tooth (NIT). METHODS Bilateral mandibular third or fourth premolars of six beagle dogs were randomly assigned to IT and NIT groups. Before extraction, chronic dehiscence defects were created at the mesial root of mid-buccal area in IT group. Four weeks later, the mesial roots of the third and fourth premolars were extracted in all groups.ARP procedure was randomly conducted on one side of the extraction sockets using collagenated bovine bone substitutes and resorbable collagen membrane, and contralateral side was allowded spontaneous healing. After 12 weeks of healing, bone-level implants (ϕ 3.6 × 8.0 mm) were placed at the extraction sockets. Three months of ligature induced peri-implantitis and three months of spontaneous progression were allowed, with radiographs taken at each phase. Biopsies were retrieved at the implant site for histomorphometric, immunohistochemical, and polarized light-microscopic analyses. RESULTS Radiography demonstrated that the changes in the marginal bone level during the spontaneous progression period showed no significant differences between ARP and SH sites. Only small and/or nonsignificant differences in the progression of peri-implantitis were observed between ARP and SH sites in histomorphometric, immunohistochemical, and polarized light microscopic analyses. Additionally, the IT and NIT groups exhibited similar outcomes for most parameters. CONCLUSION ARP with xenogenic bone substitutes might provide similarly robust results as SH sites regarding the progression of experimental peri-implantitis, irrespective of the infected or noninfected nature of the site before tooth extraction.

中文翻译：

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感染和非感染牙齿牙槽嵴保留和自发愈合部位实验性种植体周围炎的临床前比较研究：一项随机盲法体内研究。


背景 本研究比较了感染 （IT） 和非感染牙齿 （NIT） 的牙槽嵴保留 （ARP） 和自发愈合 （SH） 部位之间实验性种植体周围炎的进展。方法 将 6 只比格犬的双侧下颌第三或第四前磨牙随机分配到 IT 组和 NIT 组。拔除前，IT 组颊中区近中根部产生慢性裂开缺损。4 周后，提取所有组第三和第四前磨牙的近中根。使用胶原化牛骨替代品和可吸收胶原膜在拔牙窝的一侧随机进行 ARP 手术，对侧允许自发愈合。愈合 12 周后，将骨水平植入物 （φ 3.6 × 8.0 mm） 放置在拔牙窝处。允许 3 个月的结扎诱导的种植体周围炎和 3 个月的自发进展，在每个阶段拍摄 X 光片。在植入部位取回活检，用于组织形态学、免疫组化和偏振光显微镜分析。结果 X 线摄影显示，自发进展期边缘骨水平的变化显示 ARP 和 SH 部位之间无显著差异。在组织形态学、免疫组织化学和偏振光显微镜分析中，ARP 和 SH 部位在种植体周围炎进展中仅观察到微小和/或无统计学差异。此外，IT 组和 NIT 组在大多数参数上表现出相似的结果。 结论 异种骨替代物的 ARP 可能在实验性种植体周围炎的进展方面提供与 SH 部位类似的稳健结果，无论拔牙前该部位的感染或非感染性质如何。