Fundermental examination about support capability of dental implants at the bone developed by the maxillary sinus lift

本研究探讨了上颌窦提升和提升手术中使用各种移植材料形成的骨组织的特性。评估新形成的骨作为种植体支撑基质的活力（机械性能）和与种植体的组织学亲和力。在剃除4只Beagle犬的吻侧区域后，做了一个皮肤切口，并创建了一个粘骨膜瓣。然后暴露两侧额窦的前壁，并使用电动牙科发动机创建约10 × 20毫米的开口。小心地抬高窦膜以避免撕裂和植骨材料紧密地填入间隙。移植材料分为4组：1组为下颌骨自体骨，磨成小块；第2组，不可吸收HA；第三组，可吸收HA；第4组，自体骨与透明质酸混合。每种移植材料被放置在每只实验动物的2个不同的位置。术后6个月，取移植部位的组织标本，制作组织学标本，每个移植部位置入2个钛种植体。植入6个月后，对植入物进行扭矩测试。制备抛光脱矿切片，观察4种植骨材料形成的骨组织差异。自体骨移植组、自体骨移植+HA组和不可吸收HA组的扭矩值分别为45N-cm、41N-cm和28N-cm。不可吸收HA组的扭矩值明显低于两个自体骨组。在后续研究中，由于测试样本数量少，以及必须确保植入体放置部位皮质骨厚度的一致性，这些都是必须解决的因素。

The present study investigated the properties of bone tissue formed using various graft materials in maxillary sinus lift and elevation procedures. Newly formed bone was assessed in terms of viability as a supporting matrix for implants (mechanical properties) and histological affinity to implant bodies.After shaving the rostral region of 4 Beagle dogs, a skin incision was made and a mucoperiosteal flap was created. The anterior walls of the frontal sinus on both sides were then exposed and an electrical dental engine was used to create openings measuring approximately 10 × 20 mm. The sinus membrane was elevated carefully to avoid tearing and bone grafting materials packed tightly into the space. The grafting materials were divided into 4 groups: Group 1, autogenous bone harvested from the mandible and ground into small pieces; Group 2, non-resorbable HA; Group 3, resorbable HA; and Group 4, autogenous bone mixed with HA. Each grafting material was placed in 2 separate locations in each of the experimental animals. Six months after the operation, tissue samples from the grafted sites were collected by trephination in order to prepare ^histological samples and 2 titanium implants were inserted into each of the grafted sites. Six months after placement, torque tests on the implants were conducted. Polished demineralized sections were also prepared in order to examine the differences in osseous tissue formed by the 4 bone grafting materials.The autogenous bone graft group, the autogenous bone graft+HA group and the non-resorbable HA group gave torque values of 45N-cm, 41N-cm and 28N-cm, respectively. The torque value of the non-resorbable HA group was significantly lower in comparison to the two autogenous bone groups. The small number of test samples and the necessity to ensure consistency in the thickness of the cortical bone at the implant placement sites are factors that must be addressed in follow-up studies.