Dimensional changes of graft materials following maxillary sinus floor augmentation: A radiographic study

Objectives: Dental implants frequently require prior bone augmentation. The aim of this study was to analyze how the graft materials used in sinus augmentation procedures alter in the period before implantation. Specifically, we placed a combination xenograft and allograft using the layering technique, where the xenograft is adjacent to the sinus membrane, with the allograft filling the remaining sinus cavity. Method and materials: Cone beam computed tomography (CBCT) scans obtained before treatment, prior to implant placement, and following rehabilitation were available for 16 patients who underwent bilateral sinus augmentation. Linear regression, one-way ANOVA and Pearson's and Spearman's correlations were used for statistical analysis. P values ≤ 0.05 were considered statistically significant. Results: The graft size decreased over time, at a rate of 1.55 mm2 (95 % CI, −2.72 to −0.39) loss of maximum augmented bone height per month. The changes in the amount of bone filler material were significantly related to implant diameter (t = 3.25, p = 0.01), with larger implant diameters being associated with greater reductions in graft dimensions. There was no statistically significant variation in the rate of change across the three evaluated locations (p = 0.81). Conclusion: Larger implant diameters were significantly associated with greater reductions in graft dimensions, highlighting the importance of considering implant size when planning augmentation procedures and treatment timing.