Clinical Scenario
Patient sustained a severe horizontal and vertical maxillary defect from trauma.
Definitive implant therapy requires staged ridge reconstruction.
Autologous grafts remain the gold standard but entail donor‑site morbidity and longer surgery.
Digital Preoperative Workflow
CBCT Acquisition
Prosthetic Back‑Planning
Virtual wax‑up of final crowns
Precise implant positions determine the volume and shape of missing bone
CAD Design of Allograft Blocks
Two patient‑specific human allograft blocks (living‑donor origin)
Blocks 3D‑printed in bone substitute and delivered ready to hydrate
Stage 1: Onlay Block Placement
Reflect a full‑thickness flap to expose defect margins.
Hydrate blocks in saline for ≥ 30 minutes.
Trial‑fit blocks; no intraoperative trimming needed.
Fixate each block with two 1.2 mm titanium screws for rotational stability.
Achieve tension‑free, two‑layer primary closure over the blocks.
Healing Phase (5–6 Months)
Strict 5–6 month interval minimizes graft resorption risk.
Optional postoperative OPG provides a baseline.
Stage 2: Implant Placement & Contour Augmentation
Re‑expose augmented ridge and remove fixation screws.
Use a surgical guide to place implants exactly in prosthetically planned positions.
Perform minor contour grafting (particulate allograft + resorbable membrane) to protect the crestal bone.
Employ minimal flap design if adequate keratinized tissue is present.
Prosthetic Phase
After another 5–6 month osseointegration period, deliver final restorations in collaboration with the prosthetics team.
Advantages
Eliminates donor‑site morbidity associated with autografts.
Custom block fit achieves precise ridge dimensions.
Shortens operative time and improves patient comfort.
Indications
Large, well‑defined posterior maxillary defects requiring ≥ 5 months of undisturbed healing.
Patients who cannot tolerate autograft harvesting.
Limitations
Not a substitute for all augmentation needs—autografts, xenografts, and particulate techniques remain essential for smaller or irregular defects.
Requires strict adherence to timing to avoid resorption.
Take‑Home Message: Patient‑specific allograft onlay blocks offer a predictable, low‑morbidity solution for staged ridge reconstruction in large posterior maxillary defects, facilitating optimal conditions for subsequent implant placement.