BACKGROUND This study evaluated the effect of two self-tapping implants on implant stability in immediate implantation. METHODS Two types of self-tapping implants, straight flute (STF) and spiral flute (SPF) designs, were studied. Two synthetic bone blocks with varying densities (0.32 g/cm3 and 0.16 g/cm3) were chosen to simulate the bone quality of the anterior maxilla. Insertion torque values were measured by a torque testing machine during implant insertion. Four biomechanical tests were performed: resonance frequency analysis was conducted using the Osstell device, and the strengths of screw push-in, lateral bending, and pull-out were evaluated using an MTS machine. The strength for each design feature was obtained by averaging the results of 10 trials. In total, 40 specimens were tested for each bone density. Statistical difference was determined by one-way analysis of variance followed by Bonferroni post hoc multiple tests between groups. FINDINGS The STF and SPF groups exhibited similar insertion torque values (p = 0.525 in low-density bone, and p = 0.99 in high-density bone). A significant difference (p < 0.001) was observed in the push-in test between the two groups when low-density bone was tested. The SPF group exhibited a significantly higher lateral bending force (p = 0.001) and a higher stiffness (p < 0.001) than the STF group in high-density bone. The SPF design attained higher (p < 0.001) ISQ numbers than the STF design, but all numbers were below 60. INTERPRETATION Implant stability can be influenced by the apical fixture design of self-tapping implants in immediate implantation.

中文翻译：

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种植体设计对两种自攻牙种植体的初始生物力学稳定性的影响。

背景技术该研究评估了两种自攻植入物对即时植入中植入物稳定性的影响。方法研究了两种类型的自攻植入物，直槽（STF）和螺旋槽（SPF）设计。选择两个密度不同的合成骨块（0.32 g / cm3和0.16 g / cm3）来模拟上颌前骨的骨质量。在植入物插入期间通过扭矩测试机测量插入扭矩值。进行了四个生物力学测试：使用Osstell装置进行共振频率分析，并使用MTS机器评估螺丝推入，横向弯曲和拉出的强度。每个设计特征的强度是通过平均10次试验的结果获得的。总共测试了40个样本的每种骨密度。统计差异是通过单因素方差分析，然后进行Bonferroni组之间事后多重检验确定的。结果STF和SPF组表现出相似的插入扭矩值（在低密度骨中p = 0.525，在高密度骨中p = 0.99）。当测试低密度骨时，两组的推入测试中观察到显着差异（p <0.001）。在高密度骨中，SPF组显示出比STF组明显更高的侧向弯曲力（p = 0.001）和更高的刚度（p <0.001）。SPF设计获得的ISQ值高于STF设计（p <0.001），但所有数字均低于60。解释种植体的稳定性会受到即时植入中自攻式种植体的根尖固定装置设计的影响。