Lombardi Teresa, Rapani Antonio, Ezeddine Fatima, Perazzolo Giulia, Di Lenarda Roberto, Sivolella Stefano, Stacchi Claudio
Department of Health Sciences, "Magna Græcia" University, Catanzaro, Italy.
Department of Medical, Surgical and Health Sciences, University of Trieste, Trieste, Italy.
Clin Implant Dent Relat Res. 2025 Feb;27(1):e13428. doi: 10.1111/cid.13428. Epub 2024 Dec 15.
Short implants are today a reliable, minimally invasive option for the rehabilitation of the posterior maxilla. However, maintaining marginal bone stability remains a crucial factor for long-term success, particularly in the case of short implants. The present multicenter prospective case-control study aimed to compare the clinical outcomes of bone-level and tissue-level short implants in the posterior maxilla, focusing on implant survival and peri-implant marginal bone stability over 1 year of function.
Fifty-nine patients who met specific inclusion criteria were enrolled and treated by three clinical centers with a total of 74 short implants, either bone-level (7 mm in length, placed 1 mm sub-crestally) or tissue-level (5 or 6.5 mm in length). The primary outcome was physiological bone remodeling (PBR) measured via radiographs at baseline (T0), prosthesis delivery (T1), and 12 months post-loading (T2). Statistical analysis was performed to evaluate differences in PBR between groups, with multivariate analysis assessing the influence of various patient and site-specific factors.
The final analysis included 58 patients who were treated with a total of 71 short implants, comprising 36 tissue-level and 35 bone-level implants (one patient dropped out as he did not attend follow-up visits on time). All implants were rehabilitated with fixed, screwed prosthetics after 5 months, with no recorded complications up to 1 year of loading. Stability was similar between the two implant types at T0 and T1, with no significant differences in insertion torque and implant stability quotient (ISQ). Multivariate analysis revealed a significant positive correlation between insertion torque and ISQ at T0, as well as with bicortical engagement of the implant apex with the sinus floor. Tissue-level implants demonstrated significantly lower peri-implant bone remodeling (PBR) compared to bone-level implants at both T1 (0.11 ± 0.27 mm vs. 0.34 ± 0.35 mm, p = 0.004) and T2 (0.30 ± 0.23 mm vs. 0.55 ± 0.42 mm, p = 0.003). Multivariate analysis showed a significant positive correlation between PBR (T0-T1) and thin vertical mucosal thickness (≤ 2 mm) at T0 in both tissue-level and bone-level implants. Additionally, PBR (T1-T2) in both groups significantly correlated with the use of short prosthetic abutments (≤ 2 mm) and, only in bone-level implants, with crown emergence angles > 30°.
Both tissue-level and bone-level short implants are effective options for implant-supported rehabilitation in the posterior maxilla. Tissue-level short implants offer superior marginal bone stability compared to bone-level implants placed subcrestally, suggesting their favorable use in clinical practice.
如今，短种植体是上颌后牙区修复的一种可靠的微创选择。然而，保持边缘骨稳定性仍然是长期成功的关键因素，尤其是对于短种植体而言。本多中心前瞻性病例对照研究旨在比较上颌后牙区骨水平和软组织水平短种植体的临床效果，重点关注种植体在1年功能期内的存留率和种植体周围边缘骨稳定性。
59例符合特定纳入标准的患者入组，由三个临床中心进行治疗，共植入74枚短种植体，包括骨水平种植体（长度7mm，植入牙槽嵴顶下1mm）或软组织水平种植体（长度5或6.5mm）。主要观察指标是通过基线（T0）、义齿戴入（T1）和加载后12个月（T2）的X线片测量生理骨改建（PBR）。进行统计分析以评估组间PBR的差异，多变量分析评估各种患者和部位特异性因素的影响。
最终分析纳入58例患者，共植入71枚短种植体，其中36枚软组织水平种植体和35枚骨水平种植体（1例患者因未按时参加随访而退出）。所有种植体在5个月后用固定螺丝固位义齿修复，加载1年内未记录到并发症。两种种植体类型在T0和T1时的稳定性相似，植入扭矩和种植体稳定性商数（ISQ）无显著差异。多变量分析显示，T0时植入扭矩与ISQ之间以及种植体根尖与窦底的双皮质接触之间存在显著正相关。在T1（0.11±0.27mm对0.34±0.35mm，p = 0.004）和T2（0.30±0.23mm对0.55±0.42mm，p = 0.003）时，软组织水平种植体的种植体周围骨改建（PBR）均显著低于骨水平种植体。多变量分析显示，软组织水平和骨水平种植体在T0时PBR（T0-T1）与薄的垂直黏膜厚度（≤2mm）之间均存在显著正相关。此外，两组的PBR（T1-T2）均与使用短修复基台（≤2mm）显著相关，且仅在骨水平种植体中与冠边缘角度>30°相关。
软组织水平和骨水平短种植体都是上颌后牙区种植支持修复的有效选择。与牙槽嵴顶下植入的骨水平种植体相比，软组织水平短种植体具有更好的边缘骨稳定性，表明其在临床实践中的良好应用前景。
