Beta-Tricalcium Phosphate Grafting of Peri-implant Jumping Gaps Greater Than 2 mm in Immediate Implants

This randomized controlled trial evaluated whether grafting the peri-implant "jumping gap" with injectable β-tricalcium phosphate (β-TCP) improves outcomes after immediate implant placement in sites where the horizontal gap between the implant surface and the surrounding socket wall exceeds 2 mm. Sixteen patients (a total of 39 immediate implants in the maxillary anterior and premolar regions) were randomly allocated in a 1:1 ratio to a test group (peri-implant gap filled with injectable β-TCP) or a control group (no grafting). The patient was the unit of analysis. The primary outcome was implant stability, measured by resonance frequency analysis and expressed as the implant stability quotient (ISQ) at baseline, 3 months, and 6 months. The secondary outcome was peri-implant bone density, monitored on standardized digital periapical radiographs (baseline, 3, and 6 months) and quantified at 6 months by a single cone-beam computed tomography (CBCT) scan.