Makary Christian, Menhall Abdallah, Zammarie Carole, Lombardi Teresa, Lee Seung Yeup, Stacchi Claudio, Park Kwang Bum
Department of Oral Surgery, St Joseph University, Beirut 17-5208, Lebanon.
Private practice, Beirut 17-5208, Lebanon.
Materials (Basel). 2019 Jul 27;12(15):2398. doi: 10.3390/ma12152398.
Macro- and micro-geometry are among the factors influencing implant stability and potentially determining loading protocol. The purpose of this study was to test a protocol for early loading by controlling implant stability with the selection of fixtures with different thread depth according to the bone density of the implant site. Patients needing implant therapy for fixed prosthetic rehabilitation were treated by inserting fixtures with four different thread diameters, selected based on clinical assessment of bone quality at placement (D1, D2, D3, and D4, according to Misch classification). Final insertion torque (IT) and implant stability quotient (ISQ) were recorded at baseline and ISQ measurements repeated after one, two, three, and four weeks. At the three-week measurement (four weeks after implant replacement), implants with ISQ > 70 Ncm were functionally loaded with provisional restorations. Marginal bone level was radiographically measured 12 months after implant insertion. Fourteen patients were treated with the insertion of forty implants: Among them, 39 implants showing ISQ > 70 after 3 weeks of healing were loaded with provisional restoration. Mean IT value was 82.3 ± 33.2 Ncm and varied between the four different types of bone (107.2 ± 35.6 Ncm, 74.7 ± 14.0 Ncm, 76.5 ± 31.1 Ncm, and 55.2 ± 22.6 Ncm in D1, D2, D3, and D4 bone, respectively). Results showed significant differences except between D2 and D3 bone types. Mean ISQ at baseline was 79.3 ± 4.3 and values in D1, D2, D3, and D4 bone were 81.9 ± 2.0, 81.1 ± 1.0, 78.3 ± 3.7, and 73.2 ± 4.9, respectively. Results showed significant differences except between D1 and D2 bone types. IT and ISQ showed a significant positive correlation when analyzing the entire sample (p = 0.0002) and D4 bone type (p = 0.0008). The correlation between IT and ISQ was not significant when considering D1, D2, and D3 types (p = 0.28; p = 0.31; p = 0.16, respectively). ISQ values showed a slight drop at three weeks for D1, D2, and D3 bone while remaining almost unchanged in D4 bone. At 12-month follow-up, all implants (39 early loading, 1 conventional loading) had satisfactory function, showing an average marginal bone loss of 0.12 ± 0.12 mm, when compared to baseline levels. Conclusion: Matching implant macro-geometry to bone density can lead to adequate implant stability both in hard and soft bone. High primary stability and limited implant stability loss during the first month of healing could allow the application of early loading protocols with predictable clinical outcomes.
宏观和微观几何形状是影响种植体稳定性并可能决定加载方案的因素之一。本研究的目的是通过根据种植部位的骨密度选择具有不同螺纹深度的种植体来控制种植体稳定性，从而测试一种早期加载方案。需要进行种植治疗以进行固定义齿修复的患者，通过植入具有四种不同螺纹直径的种植体进行治疗，这些种植体是根据植入时对骨质量的临床评估来选择的（根据米施分类法分为D1、D2、D3和D4）。在基线时记录最终植入扭矩（IT）和种植体稳定性商数（ISQ），并在一、二、三、四周后重复进行ISQ测量。在三周测量时（种植体植入后四周），ISQ > 70 Ncm的种植体进行功能性加载临时修复体。在种植体植入12个月后通过X线片测量边缘骨水平。14例患者共植入40颗种植体：其中，39颗种植体在愈合3周后ISQ > 70，进行了临时修复体加载。平均IT值为82.3 ± 33.2 Ncm，在四种不同类型的骨中有所不同（D1、D2、D3和D4骨中的IT值分别为107.2 ± 35.6 Ncm、74.7 ± 14.0 Ncm、76.5 ± 31.1 Ncm和55.2 ± 22.6 Ncm）。结果显示除D2和D3骨类型之间外，其他均有显著差异。基线时的平均ISQ为79.3 ± 4.3，D1、D2、D3和D4骨中的值分别为81.9 ± 2.0、81.1 ± 1.0、78.3 ± 3.7和73.2 ± 4.9。结果显示除D1和D2骨类型之间外，其他均有显著差异。在分析整个样本（p = 0.0002）和D4骨类型（p = 0.0008）时，IT和ISQ显示出显著的正相关。在考虑D1、D2和D3类型时，IT和ISQ之间的相关性不显著（分别为p = 0.28；p = 0.31；p = 0.16）。D1、D2和D3骨的ISQ值在三周时略有下降，而D4骨的ISQ值几乎保持不变。在12个月的随访中，所有种植体（39颗早期加载，1颗传统加载）功能良好，与基线水平相比，平均边缘骨吸收为0.12 ± 0.12 mm。结论：使种植体宏观几何形状与骨密度相匹配可在硬骨和软骨中均实现足够的种植体稳定性。高初始稳定性以及愈合第一个月内有限的种植体稳定性丧失可允许应用早期加载方案并获得可预测的临床结果。
