The primary aim of this randomized clinical trial is to evaluate the influence of subcrestal implant placement depth (-2 mm vs -4 mm) on peri-implant marginal bone level changes, including marginal bone loss and bone remodeling. Secondary outcomes include implant success, peri-implant probing depth (PPD), and bleeding on probing (BoP).
Partially edentulous patients requiring fixed implant-supported prosthetic rehabilitation with two implants in posterior maxillary or mandibular regions will be included. Implants will be placed subcrestally at either -2 mm or -4 mm from the bone crest, following a submerged healing protocol. Allocation to insertion depth will be randomized. Marginal bone level changes will be assessed using standardized periapical radiographs at second-stage surgery, prosthesis placement, and at 1, 3, 6, and 12 months after functional loading. PPD and BoP will be recorded at the same time points.
Patients ≥18 years old with partial edentulism.
Need for rehabilitation with fixed implant-supported prostheses in posterior regions.
Availability of minimum bone height for implants ≥6 mm in length.
Minimum bone width without the need for guided bone regeneration.
Systemic diseases contraindicating implant surgery.
Treatment with intravenous bisphosphonates.
Head and neck radiotherapy.
Uncontrolled diabetes.