Bone Microarchitecture at Augmented Maxillary Sinus Sites

Micro computed tomography (micro-CT) is now a widely used procedure for analyzing the stracture of hard tissues due to its quick, reproducible and non-invasive properties. The aim of this study was to analyze the bone microarchitecture at augmented maxillary sinus sites and to in patient compare the effect of porous titanium granules as a sinus augmentation material to bone microstructural features.

Methods:

Eight patients were treated with bilateral sinus augmentation procedure using bovine bone and bovine bone (1 gr) + porous titanium (1 gr) granules. After 6 months of healing bone biopsies were retrieved from 16 implant sites by a standart trephine bur. The specimens were scanned with a Micro CT system. All specifications of the program was used to analyze the 3-D microarchitecture of each sample, and to calculate 10 structural parameters in each bone sample over the entire volume of the specimen as; tissue volume (TV), bone volume (BV), percent bone volume (BV/TV), trabecular thickness (Tb.Th), and trabecular pattern factor (Tb.Pf) , bone surface (BS), bone-specific surface (BS/BV), bone surface density (BS/TV), trabecular separation (Tb. Sp), trabecular number (Tb.N), and structure model index (SMI), closed porosity of bone (CPB), fractal dimension (FD).

Results:

No significant differences were found between groups according to bone structural parameters. Significant correlations were found in test group according to Tb.Th mm and mean fractal dimension, Tb.PF mm^-1 and BS/TV mm^-1, SMI and BS/TV mm^-1, BS/TV mm^-1 and BS/BV mm^-1, BS mm² and Tb.PF mm^-1.

Conclusion:

Porous titanium granules as a sinus augmentation material showed no significant differences according to bone structural parameters however its porosity ensures a space for new bone formation into the granules. Three dimensional analyzing the augmented bone microarchitecture by micro-CT may be a useful tool to understand the mechanisms underlying the bone healing process.