Caramês João Manuel Mendez, Francisco Helena Cristina Oliveira, Vieira Filipe Araújo, Caramês Gonçalo Bártolo, Martins Jorge Nuno do Rosário, Marques Duarte Nuno da Silva
Instituto de Implantologia, Avenida Columbano Bordalo Pinheiro, No. 50, 1070-064 Lisbon, Portugal.
Faculdade de Medicina Dentária, Universidade de Lisboa, 1600-277 Lisbon, Portugal.
J Clin Med. 2025 Jun 14;14(12):4237. doi: 10.3390/jcm14124237.
The potential impact of the number of implants (four vs. six) on the implant survival of implant-supported fixed complete dentures (IFCDs) remains inconclusive and subject to ongoing debate. This study compared the implant survival of immediately loaded four vs. six IFCDs, delivered using a patient-centered systematic treatment plan, in a large patient cohort assessed with consistent diagnostic methodology and comprehensive longitudinal follow-up. This retrospective study included records of 943 patients receiving 5989 implants with an average follow-up of 5.0 ± 3.2 (range 0-17) years delivered using a systematic clinical decision support system (CDSS) based on a defined alveolar atrophy classification (CC). Implant survival was analyzed considering predictor variables comprising treatment and anatomic and systemic health-related factors at the overall, maxillary, and mandibular levels using Kaplan-Meier analysis, log-rank tests, and single-predictor and multilevel Cox proportional hazard analysis derived from causal direct acyclic graph methodologies. The 2- and 5-year cumulative survival rates (CSRs) of four and six IFCDs were comparable (2-year: 98.6% vs. 98.4%, = 0.362; 5-year: 98.8%, 98.7% = 0.346). The differences between four and six IFCDs were more pronounced at the maxillary levels, specifically after 2 years (97.7% vs. 98.6% = 0.084), and at the mandibular level after 5 years (98.6% vs. 99.4%, = 0.136.). Multilevel Cox proportional hazard models at overall and jaw levels adjusted for confounding factors indicated that implant loss was correlated to jaw type and age at overall and age alone at the mandibular level. Alveolar atrophy (CC) defined within the adopted CDSS was not robustly associated with implant loss. Under the guidance of a systematically applied patient-centered CDSS, four and six IFCDs demonstrated high and comparable mid-to-long-term implant survival rates irrespective of the level of analysis or statistical model used to adjust for confounding factors. Prosthetic and technical complications were not evaluated and were, therefore, beyond the scope of this study.
种植体数量（4颗与6颗）对种植体支持的固定全口义齿（IFCD）种植体存留率的潜在影响尚无定论，仍在持续争论中。本研究比较了采用以患者为中心的系统治疗计划即刻加载的4颗与6颗IFCD的种植体存留率，该研究纳入了一大群患者，采用一致的诊断方法进行评估并进行全面的纵向随访。这项回顾性研究纳入了943例接受5989颗种植体的患者记录，平均随访时间为5.0±3.2（范围0 - 17）年，使用基于定义的牙槽骨萎缩分类（CC）的系统临床决策支持系统（CDSS）进行治疗。使用Kaplan - Meier分析、对数秩检验以及源自因果直接无环图方法的单预测因子和多级Cox比例风险分析，在总体、上颌和下颌水平上分析种植体存留率，同时考虑包括治疗以及与解剖和全身健康相关的预测变量。4颗和6颗IFCD的2年和5年累积存留率（CSR）具有可比性（2年：98.6%对98.4%，P = 0.362；5年：98.8%，98.7%，P = 0.346）。4颗和6颗IFCD之间的差异在上颌水平更为明显，特别是在2年后（97.7%对98.6%，P = 0.084），在下颌水平在5年后（98.6%对99.4%，P = 0.136）。在总体和颌骨水平上针对混杂因素进行调整的多级Cox比例风险模型表明，种植体丢失与颌骨类型相关，在总体水平以及仅在下颌水平与年龄相关。在采用的CDSS中定义的牙槽骨萎缩（CC）与种植体丢失没有密切关联。在系统应用的以患者为中心的CDSS指导下，无论用于调整混杂因素的分析水平或统计模型如何，4颗和6颗IFCD均显示出较高且可比的中长期种植体存留率。本研究未评估修复和技术并发症，因此超出了本研究的范围。
