Influence of osteoporosis and mechanical loading on bone around osseointegrated dental implants: A rodent study
Influence of osteoporosis and mechanical loading on bone around osseointegrated dental implants: A rodent study
复制标题
DOI：
10.1016/j.jmbbm.2021.104771
复制
发表时间：
2021-08-23
影响因子：
3.9
通讯作者：
Ayukawa, Yasunori
中科院分区：
文献类型：
--
作者：
Chen, Xi;Moriyama, Yasuko;Ayukawa, Yasunori
本研究旨在评价雌激素缺乏和机械负荷对大鼠下颌骨种植体周围骨的影响。拔除36只大鼠的上颌右第一磨牙。一周后，将大鼠分为未负荷组和负荷组，分别植入短头种植体和长头种植体。植入9周后，进一步接受卵巢切除(OVX)或假手术。所有动物在去卵巢21周后安乐死。进行显微计算机体层摄影、组织学和组织形态计量学评价。与假手术组相比，去卵巢组大鼠全身骨密度和骨体积分数均降低。组织形态计量学观察显示，去卵巢组与去卵巢组相比，骨结合明显受损，骨丢失明显。OVX组种植体周围槽内骨密度(BD)和种植体骨-种植体接触率(BIC)均低于假手术组，而机械负荷OVX组BIC和BIC明显高于非OVX组。与假手术对照组相比，OVX组耐酒石酸酸性磷酸酶阳性细胞数增加。OVX组和假手术组在负重状态下，硬化素阳性骨细胞的百分比均低于非负重状态。综上所述，雌激素缺乏可能是骨整合种植体长期稳定性的危险因素，而机械负荷可以减轻雌激素缺乏对骨形成和骨整合的负面影响。
This study aimed to evaluate the influence of estrogen deficiency and mechanical loading on bone around osseointegrated dental implants in a rat jaw model. The maxillary right first molars of 36 rats were extracted. One week later, the rats were divided into an unloaded group and a loaded group; short head implants and long head implants were inserted respectively. Nine weeks after implantation, the rats were further subjected to ovariectomy (OVX) or sham surgery. All animals were euthanized 21 weeks after OVX. Micro-computed tomography, histological and histomorphometrical evaluation were undertaken. Systemic bone mineral density and bone volume fraction decreased in OVX groups compared with the sham controls. Histomorphometrical observation indicated that unloaded OVX group showed significantly damaged osseointegration and bone loss versus the loaded OVX group. Both the bone density (BD) inside the peri-implant grooves and the percentage of bone-to-implant contact (BIC) were lower in the OVX groups than in the sham-surgery groups, although mechanical loading increased the BIC and BD in the loaded OVX group compared with the unloaded OVX group. An increased number of positive cells for tartrate-resistant acid phosphatase was observed in the OVX groups versus the sham controls. The percentage of sclerostin-positive osteocytes was lower under loaded compared with unloaded conditions in both the OVX groups and the sham controls. In conclusion, estrogen deficiency could be a risk factor for the long-term stability of osseointegrated implants, while mechanical loading could attenuate the negative influence of estrogen deficiency on bone formation and osseointegration.