Dental Implant Osseointegration Following Mandibular Augmentation Using 3D Printed Hydroxyapatite Blocks. An Experimental In Vivo Study.

OBJECTIVE

To evaluate the use and osseointegration of dental implants in combination with 3D-printed hydroxyapatite (3DHA) blocks featuring gyroid porosity for large mandibular bone augmentation.

METHODS

Mandibular lateral bone augmentation with gyroid-3DHA blocks was performed bilaterally on four female Göttingen minipigs. After 8 or 12 weeks of healing, a dental implant was placed into each 3DHA block. Following an additional 12-week healing period, the augmented sites (including 3DHA blocks and dental implants) were harvested for histological and histomorphometric analysis, assessing new bone formation, 3DHA integration, total bone gain, and bone-to-implant contact (BIC).

RESULTS

Gyroid-3DHA blocks were easily fixated with screws. Dental implants were placed through the 3DHA blocks with a standard drilling procedure, and good primary stability was achieved. 3DHA blocks demonstrated good osseointegration with 39.17% of new bone and a significant bone gain of 4.73 mm on average. Dental implants showed comparable BIC within the 3DHA and into the native bone (42.79% vs. 34.17%). No significant difference was found between the healing periods.

CONCLUSION

This is the first study to evaluate a 3D-printed bone substitute in combination with a dental implant in an animal study. Gyroid-3DHA blocks and dental implants demonstrated good osseointegration, and the bone augmentation was significant, making it a promising material for large and complex alveolar ridge augmentations.