Clinical parameters of implants placed bone level with cover screw or healing abutment techniques. 6 months post-surgery report from a randomized controlled clinical trial.

OBJECTIVE

This randomized clinical trial evaluated marginal bone level (MBL) changes and peri-implant soft tissue health in single implants placed at crestal bone level, comparing healing abutments exposed at gingival level versus cover screws submerged with a flap.

METHODS

Sixty-six PrimeTaper implants (Dentsply, Mannheim, Germany) were placed in 45 healthy adult patients and randomized to either the healing abutment group (n = 34) or the cover screw group (n = 32). A fully digital workflow was used for provisional and definitive zirconia crowns delivered at 3-4 months. Clinical and radiographic follow-ups were performed at baseline, 3 and 6 months. Outcomes included Bleeding upon Scanbody positioning (BuSP), bleeding upon Prosthetic Abutment application (BuPA) and Mombelli modified plaque score, MBL, and prosthetic complications.

RESULTS

Baseline characteristics were balanced between groups. Implant survival was 100%, with one mucositis case in the healing abutment group. Soft tissue assessment revealed reduced BuSP in the healing abutment group, where approx. 75% of implants showed no BuPA at follow-up (p < 0.001). Mombelli modified plaque score improved over time and did not differ significantly between groups.

CONCLUSION

Both techniques yielded stable peri-implant tissues and comparable MBL changes at 6 months. Healing abutment application reduced bleeding during prosthetic clinical procedures and avoided flap re-entry, offering a simpler, less invasive, and equally effective alternative to cover screw protocols.