One-Abutment-One-Time Versus Repeated Abutments Disconnections in Platform-Switched Conical Connection Dental

The one-abutment-one-time protocol has been proposed to improve peri-implant tissue stability by minimizing repeated abutment manipulation. This systematic review and meta-analysis evaluated the effect of one-abutment-one-time compared with repeated abutment disconnections on peri-implant marginal bone loss and secondary clinical outcomes in platform-switched, conical-connection dental implants.

A PRISMA-guided systematic review of randomized controlled trials published between 2018 and 2025 was conducted. Studies included adult patients restored with bone-level, platform-switched implants with an internal conical connection. Marginal bone loss (MBL) was the primary outcome; probing depth (PD), implant survival, and biological and prosthetic complications were secondary outcomes. Meta-analyses were performed using random-effects models.

Seven randomized controlled trials were included. All studies reported numerically lower MBL with one-abutment-one-time (OAOT). Pooled analysis of six parallel-group trials demonstrated a statistically significant reduction in MBL favouring OAOT (mean difference -0.23 mm; 95% CI = -0.44 to -0.02). No significant differences were observed for PD. Implant survival rates were high and comparable between protocols, and complication rates were low with no consistent intergroup differences.

The one-abutment-one-time protocol is associated with a modest but consistent reduction in peri-implant marginal bone loss in platform-switched, conical-connection implants, without clear benefits for other peri-implant clinical outcomes.