Early Hard- and Soft-tissue Response to a Novel Long-cuff Implant with a Microgrooved Neck Surface: A Proof-of-concept Study

Purpose: This proof-of-concept animal study evaluated the early hard-and soft-tissue responses to a novel long-cuff implant that incorporates a long, machined neck with a microgrooved surface.Materials and Methods: Six beagle dogs received both conventional (control) and novel long-cuff (test) implants in the mandible following a 2-month healing period after tooth extraction.Each animal was fitted with one control implant and five test implants, randomly distributed across three sites on each side of the mandible.Radiological and histological assessments were performed at 2, 4, and 6 weeks.Outcome measures included inflammatory response, bone volume/tissue volume (BV/TV), bone-to-implant contact (BIC), bone area (BA), soft-tissue attachment, and collagen density.Results: Both implant types exhibited comparable inflammatory patterns, peaking at 4 weeks and resolving by 6 weeks.BV/TV remained stable over time (control: 17.89 5.06%; test: 20.18 2.25% at 6 weeks).At 6 weeks, the microgroove surface demonstrated greater soft-tissue attachment (85.98 20.64%) and collagen density (25.12 13.64%) than the machined surface (62.76 28.03% and 14.14 9.56%, respectively) and the control group (69.42 13.15% and 19.70 4.40%, respectively).BIC and BA followed similar trajectories in both groups; at 6 weeks, BIC reached 18.27 0.34% in controls and 15.90 14.08% in the test group.