Objective

To assess longitudinal peri-implant tissue evaluation in a plaque compromised ligature free dog model, clinically, radiographically, microbiologically and histologically.

Materials and methods

Six beagle mandibular premolars and first molars were extracted. Plaque accumulated for 16 weeks. Two implants were placed per hemi-mandible. For 17 weeks, control implants (CI) in one hemi-mandible were brushed daily; test implants (TI) in the other were not. These parameters were then assessed: clinically, probing depth (PD), bleeding-on-probing (BOP), presence of plaque (PP) and clinical attachment level (CAL); radiographically, marginal bone level; microbiologically, counts for Streptococcus spp., Fusobacterium spp., Porphyromonas gingivalis, Aggregatibacter actinomycetemcomitans, Prevotella intermedia and total bacterial load. At week 17, histomorphometric analysis was performed (MM-ISH (mucosal margin–implant shoulder); ISH-fBIC (implant shoulder–first bone-to-implant contact); MM-aJE (mucosal margin–apical area junctional epithelium); MM-aINF (mucosal margin–apical limit of the inflammatory infiltrate); %INF (percentage of inflammatory infiltrate)).

Results

At week 17, TI had significant increased PD, BOP, PP and CAL versus baseline. All clinical variables presented intergroup differences. There was no intergroup difference for radiographic bone loss (p > 0.05). Total bacteria, Fusobacterium spp., A. actinomycetemcomitans and P. gingivalis had intergroup differences. There was no statistically significant intergroup difference for ISH-fBIC.

Conclusions

Longitudinal microbiology evaluation detected a shift period. Final intergroup microbiological differences were the basis of W17 clinical intergroup differences, with higher values in TI. Microbiological and clinical changes detected in peri-implant tissues were compatible with onset of peri-implant disease. Despite histological inflammatory intergroup difference, no histological or radiographic intergroup bone loss was detected.

Clinical relevance

This study set-up describes a valuable method for generating “true” early peri-implant defects without mechanical trauma.

中文翻译：

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评估一种新的犬周围疾病的动物模型：临床，影像学，微生物学和组织学评估。

目的

为了评估斑块受损的无结扎自由犬模型的纵向种植体周围组织评估，从临床，放射学，微生物学和组织学角度进行评估。

材料和方法

提取了六个小猎犬下颌前磨牙和第一磨牙。斑块累积16周。每个半下颌放置两个植入物。在17周内，每天刷一次半下颌骨的对照植入物（CI）；另一个则没有测试植入物（TI）。然后评估这些参数：临床，探测深度（PD），探测出血（BOP），斑块存在（PP）和临床依从水平（CAL）；影像学上边缘骨水平；微生物，用于计数链球菌属，梭杆菌属，牙龈卟啉，Aggregatibacter放线，中间普氏菌和总细菌负荷。在第17周时，进行了组织形态计量学分析（MM-ISH（粘膜边缘-植入物肩）； ISH-fBIC（植入物肩膀-首次骨与植入物接触）； MM-aJE（粘膜边缘-根尖区连接上皮）； MM -aINF（粘膜边缘-炎性浸润的顶端极限）；％INF（炎性浸润的百分比）。

结果

与基线相比，在第17周，TI的PD，BOP，PP和CAL显着增加。所有临床变量均存在组间差异。影像学上的骨丢失没有组间差异（p  > 0.05）。总细菌，梭状芽孢杆菌，放线杆菌和齿龈假单胞菌之间存在群体间差异。ISH-fBIC的组间差异无统计学意义。

结论

纵向微生物学评估检测到一个转变时期。最终的组间微生物学差异是W17临床组间差异的基础，TI中的值较高。在植入物周围组织中检测到的微生物学和临床变化与植入物周围疾病的发作是相容的。尽管在组织学上炎症性组间存在差异，但未检测到组织学或影像学上的组间骨丢失。

临床相关性

这项研究设置描述了一种有价值的方法，可在没有机械损伤的情况下产生“真正的”早期种植体周围缺损。