Ivanoff C J, Gröndahl K, Bergström C, Lekholm U, Brånemark P I
Department of Oral and Maxillofacial Surgery, Mölndal Hospital, Sweden.
Int J Oral Maxillofac Implants. 2000 Jan-Feb;15(1):103-10.
The present study evaluated implant survival and marginal bone loss in maxillae over a 15-year follow-up period as a function of either monocortical or bicortical implant anchorage. Of 207 standard Brånemark implants (10 mm in length) followed, 110 implants were judged to be monocortically anchored and 97 as bicortically anchored. The bicortically anchored implants failed nearly 4 times more often than the monocortical ones. Implant fractures accounted for over 80% of the observed failures and were found to affect the bicortical group almost 3 times more often. As tentative explanations, induction of increased stress and bending forces resulting from possible prosthetic misfit, presence of unfavorable arch relationships, or high occlusal tables in combination with bicortically anchored implants have been suggested, all indicating an overambitious fixation of the bicortical anchorage. Total marginal bone loss was low over the 15-year period and close to identical for the 2 groups, suggesting that the mode of cortical anchorage did not have any clinically significant influence on marginal bone remodeling.
本研究评估了在15年的随访期内，单皮质或双皮质种植体锚固对上颌骨种植体存留率和边缘骨吸收的影响。在随访的207颗标准Brånemark种植体（长度为10mm）中，110颗种植体被判定为单皮质锚固，97颗为双皮质锚固。双皮质锚固种植体的失败率几乎是单皮质锚固种植体的4倍。种植体折断占观察到的失败病例的80%以上，并且发现双皮质锚固组受影响的频率几乎是单皮质锚固组的3倍。作为初步解释，有人提出可能是修复体不匹配、存在不利的牙弓关系或高牙合平面与双皮质锚固种植体共同作用导致应力和弯曲力增加，所有这些都表明双皮质锚固的固定过于理想。在15年期间，总的边缘骨吸收量较低，两组相近，这表明皮质锚固方式对边缘骨重塑没有任何临床上的显著影响。
