Correction of Peri‐Implant Buccal Bone Dehiscence Following Sub‐Periosteal Peri‐Implant Augmented Layer Technique With Either Block or Particulate Xenograft: A Retrospective Study

Objective: To evaluate the effectiveness of Sub-periosteal Peri-implant Augmented Layer (SPAL) technique performed with deproteinized bovine bone mineral (DBBM), delivered either as particulate (pDBBM) or block (bDBBM), in correcting a peri implant bone dehiscence (PIBD). Implants showing a thick (≥ 2 mm) peri-implant buccal bone plate (PBBP) at placement were also examined. Material and Methods: Patients with a PIBD ≥ 1 mm, treated with SPAL with either pDBBM (SPALparticulate) or bDBBM (SPALblock), and patients with an implant showing a PBBP ≥ 2 mm at insertion (CONTROL) were included. Re-entry was performed either at 6 months (SPAL groups) or 3 months (CONTROL). The rate of patients presenting no PIBD at re-entry was the primary outcome. Bone dehiscence height (BDH) and width (BDW), thickness of buccal tissues (BTT) and marginal bone level (MBL) were secondary outcomes. Results: Thirty-nine implants in 39 patients (14 in SPALparticulate,14 in SPALblock and 11 in CONTROL) were analyzed. No PIBD were found in SPALparticulate whereas in SPALblock one PIBD was present. Two patients in CONTROL presented a PIBD. A reduction in both BDH and BDW was observed in both SPALparticulate (2.7 ± 1.6 mm for BDH and 3.9 ± 0.2 mm for BDW) and SPALblock (2.5 ± 1.8 mm for BDH and 3.8 ± 1.1 mm for BDW). SPALblock showed a higher BTT than SPALparticulate at re-entry (3.6 ± 1.3 mm for SPALblock and 2.6 ± 0.6 mm for SPALparticulate, p = 0.0160). All groups showed similar MBL. Conclusion: SPAL performed with either a pDBBM or bDBBM is similarly effective in correcting a PIBD as well as in increasing BTT.