Comparative Analysis of Guided Bone Regeneration and Allograft Materials in Periodontal Implant Treatment :A Systematic Review and Meta-Analysis

Background: Guided Bone Regeneration (GBR) treatment with allograft materials finds regular use in periodontal implant procedures to rebuild the alveolar bone structure and boost implant success rates. This systematic review and meta-analysis aimed to evaluate the effectiveness of GBR with allografts versus other implant approaches to identify the most effective periodontal treatment. Methods: This systematic review and meta-analysis were conducted according to the PRISMA 2020 guidelines. The literature retrieval was conducted using PubMed, Scopus, Web of Science, and Google Scholar up to May 2025. The relevant studies compared guided bone regeneration (GBR). The Cochrane tool and Newcastle-Ottawa Scale (NOS) were used to determine risk of bias for observational studies and RCTs, respectively. The RevMan 5.4.1 was deployed to conduct meta-analyses, and pooled estimates were obtained using a random-effect model. Heterogeneity was determined by the I2 statistic. GRADE framework was used for the certainty of evidence. Results: 9 studies (5 RCTs, 3 observational, and 1 retrospective study) were included. Vertical/horizontal bone gain and peri-implant probing depth were the primary outcomes. Meta-analysis revealed significant bone gain results on GBR (SMD: 0.83, 95% CI: 0.31-1.34) and no significant difference on probing depth (SMD: 1.23, 95% CI: -0.75-3.22). Most studies had a low risk of bias. The probing depth had significant heterogeneity (I2 = 86%), whereas bone gain heterogeneity was not present (I2 = 0%). Discussion: Periodontal implant stability improves through GBR treatment beyond the use of allograft procedures, which still show effective results in clinical practice.