Influence of Maxillary Sinus Width on New Bone Formation after Transcrestal Sinus Floor Elevation: A Proof-of-Concept Prospective Cohort Study

Purpose: Graft maturation in the maxillary sinus requires adequate angiogenesis and osteoprogenitor cells migration from the surrounding bony walls: the aim of this study was to analyze the correlation between sinus cavity dimensions and new bone formation after transcrestal sinus floor elevation (tSFE). Methods: Patients needing maxillary sinus augmentation (residual crest height # 4 mm) were treated with tSFE using xenogeneic granules. Six months later, bone-core biopsies were retrieved for histological analysis in the implant insertion sites. Buccopalatal sinus width (SW) was evaluated on cone beam computed tomography, and correlations between histomorphometric and anatomical parameters were quantified by means of linear regression analysis. Results: Eight consecutive patients underwent tSFE procedures: at 6 months, average percentage of newly formed bone resulted 24.2% 6 7.9%. Statistical analysis showed a strong inverse correlation between SW and new bone formation (R2 ¼ 0.88), and a strong direct correlation between the number of exposed bone walls and new bone formation (R2 ¼ 0.82). Conclusion: Within the limitations of this proof-of-concept study, in which a restricted number of patients were analyzed, tSFE showed more predictable results in narrow than in large sinuses, in terms of new bone formation.