A novel multidimensional classification system for bone graft healing assessment in guided bone regeneration.

OBJECTIVES

The aim of this study was to identify the healing patterns of bone grafts following guided bone regeneration (GBR) and to develop a new multidimensional classification system to standardize the assessment process and support clinical decision-making.

METHODS

A retrospective analysis was conducted on patients who received dental implant placement with simultaneous GBR in the posterior mandible between March 2019 and May 2025. Radiographic assessment included graft volume change, buccal contour integrity, and implant thread exposure. Clinical evaluation at re-entry focused on graft surface texture, periosteal integrity, and implant thread exposure. Histological analysis evaluated bone maturation, collagen organization, and osteoclastic activity.

RESULTS

A total of 82 patients with 110 GBR sites were included in the analysis. Radiographic assessment identified three distinct graft healing patterns: maintained volume (57.3 %), partial resorption (38.2 %), and severe resorption with thread exposure (4.5 %). Sites with partial resorption were subclassified by buccal contour integrity as continuous (33.3 %), pitting (40.5 %), or scalloping (26.2 %). Intraoperative assessment at re-entry yielded a four-tier classification system: Class I (complete corticalization, 65.5 %), Class II (incomplete corticalization, 20.0 %), Class III (soft tissue infiltration, 10.0 %), and Class IV (severe resorption, 4.5 %). Histological findings correlated strongly with clinical classes: Class I showed mature lamellar bone surrounding graft particles; Class II featured unmineralized matrix encapsulating graft particles, and Class III exhibited fibrous tissue replacement with osteoclasts adjacent to graft fragments of varying sizes.

CONCLUSION

A novel four-tier classification system is proposed, integrating clinical, radiographic, and histological features to provide a standardized multidimensional framework for accurate evaluation and stratification of bone graft healing status following GBR.

CLINICAL SIGNIFICANCE: The multidimensional classification system provides a standardized framework for evaluating bone graft healing status after GBR, facilitating evidence-based decision-making in clinical practice.