Effect of soft tissue volume on midfacial gingival margin alterations following immediate implant placement in the esthetic zone: a 1-year randomized clinical and volumetric trial

Abstract Background The current trial evaluated the midfacial gingival margin changes, volumetric, radiographic and clinical alterations 1-year following immediate implant placement with customized healing abutment (IIP + CHA) either solely, or in combination with xenograft (IIP + Bonegraft) or with connective tissue grafting (IIP + CTG) at sites with thin labial bone in the esthetic zone. Methods Thirty-nine non-restorable maxillary teeth indicated for extraction in the esthetic zone were included. Participants were randomly assigned into three equal group; IIP + Bonegraft (Control), IIP + CTG and IIP + CHA. Midfacial gingival margin changes(mm) as primary outcome, labial soft tissue contour change(mm), interdental tissue height changes and total volume(mm 3 ) were assessed. Amount of bone labial to the implant and crestal bone level changes were also recorded. All outcomes were measured 1-year post-operative. Results The midfacial gingival margin changes demonstrated a significant difference ( P ≤ 0.05) between the groups showing -0.98, -0.74 and -1.54 mm in sites treated with IIP + Bone graft, IIP + CTG and IIP + CHA respectively after1-year. While labial soft tissue contour change (mm), total volume (mm 3 ) and distal interdental tissue height changes (mm) revealed a significant difference after one-year between the studied groups, yet mesial interdental tissue height changes showed no difference ( P > 0.05). Both IIP + Bone graft and IIP + CHA groups revealed a significant positive correlation between the total volume loss (mm 3 ) after 1 year and mid-facial gingival margin changes ( P ≤ 0.05). However, no significant correlation was observed in the IIP + CTG group ( P = 0.63). CBCT measurements showed a significant difference in crestal bone changes between the three groups ( P ≤ 0.05), yet, there was no significant difference regarding mean amount of bone labial to the implant( P > 0.05). Conclusions This investigation suggests that the mere presence of CTG simultaneous with IIP in the anterior maxilla reduced the midfacial gingival margin alterations (mm), besides, CTG decreased the overall volume loss (mm 3 ) by 5-folds compared to the other studied groups after one year. Meanwhile, using CHA alone with IIP failed to maintain the peri-implant soft tissues contour. Trial registration The current trial was retrospectively registered at Clinical trials.gov (ID: NCT05975515, Date: 27-July-2023).