Traini Tonino, Neugebauer Jörg, Thams Ulf, Zöller Joachim E, Caputi Sergio, Piattelli Adriano
Dental School, University of Chieti-Pescara, Italy.
Clin Implant Dent Relat Res. 2009 Mar;11(1):41-51. doi: 10.1111/j.1708-8208.2008.00086.x. Epub 2008 Jul 23.
Mechanical properties of bones are greatly influenced by percentages of organic and mineral constituents. Nevertheless, information about mineralization level on a microscopic scale and collagen fiber organization in peri-implant bone after immediate loading is scarce.
The aim of this work was to analyze and compare the degree of mineralization and collagen fiber orientation in alveolar bone (AB) and peri-implant bone of immediately loaded (IL) and unloaded (NL) implants.
A total of 25 dental implants of 3.8 mm in diameter and 11 mm in length were used in the present study. In five minipigs, three premolars and the first molar were removed from the left side of the mandible. Three months later, five implants for each animal were inserted. Four implants were loaded immediately with a fixed restoration, while one implant was left unloaded. After a 4-month healing period, all implants were retrieved. Circularly polarized light and scanning electron microscope with backscattered electron imaging were used to analyze both peri-implant and AB retrieved 5 mm from the implant.
The bone/implant contact ratio (BIC %) was 77.8 +/- 5.9% for the IL implants and 78.0 +/- 5.8% for the NL implants; the difference was not statistically significant (p = 0.554). In the peri-implant bone, the area related to transverse collagen fibers was 112,453 +/- 4,605 pixels for IL implants and 87,256 +/- 2,428 pixels for NL implants. In the AB, the area related to transverse collagen fibers was 172,340 +/- 3,892 pixels. The difference between groups was statistically significant (p < .001). The degree of mineralization of peri-implant bone was 137 +/- 19 gray level for IL implants and 115 +/- 24 gray level for NL implants, while in the AB, the degree of mineralization was 125 +/- 26 gray level. This difference was statistically significant (p < .001).
In this study, it was found that IL and NL implants showed the same degree of osseointegration. The bone matrix around IL implants had a higher quantity of transverse collagen fibers and presented a higher level of mineralization.
骨骼的力学性能受有机成分和矿物质成分百分比的显著影响。然而，关于即刻加载后种植体周围骨微观尺度上的矿化水平和胶原纤维组织的信息却很匮乏。
本研究旨在分析和比较即刻加载（IL）和未加载（NL）种植体的牙槽骨（AB）及种植体周围骨的矿化程度和胶原纤维取向。
本研究共使用了25颗直径3.8mm、长度11mm的牙种植体。在5只小型猪中，从下颌左侧拔除3颗前磨牙和第一磨牙。3个月后，每只动物植入5颗种植体。4颗种植体即刻进行固定修复加载，1颗种植体不加载。经过4个月的愈合期后，取出所有种植体。使用圆偏振光和带有背散射电子成像的扫描电子显微镜分析从种植体取出的5mm处的种植体周围骨和牙槽骨。
IL种植体的骨/种植体接触率（BIC%）为77.8±5.9%，NL种植体为78.0±5.8%；差异无统计学意义（p = 0.554）。在种植体周围骨中，IL种植体与横向胶原纤维相关的面积为112,453±4,605像素，NL种植体为87,256±2,428像素。在牙槽骨中，与横向胶原纤维相关的面积为172,340±3,892像素。组间差异具有统计学意义（p <.001）。IL种植体周围骨的矿化程度为137±19灰度级，NL种植体为115±24灰度级，而牙槽骨的矿化程度为125±26灰度级。这种差异具有统计学意义（p <.001）。
在本研究中，发现IL和NL种植体显示出相同程度的骨结合。IL种植体周围的骨基质具有更多的横向胶原纤维且矿化水平更高。
