Histological and ultrastructural evaluation of bone around Bio‐Oss® particles in sinus augmentation

AIM: The aim of the present study was to evaluate histological and ultrastructural features of bone surrounding Bio-Oss particles retrieved, in the same patient, 20 months and 7 years after sinus augmentation. MATERIALS AND METHODS: A 54-year patient who needed sinus elevation before implant rehabilitation participated in this study. Two bone cores at two different times were harvested from a Bio-Oss regenerated sinus and processed for examination under light and transmission electron microscopy. RESULTS: Under light microscopy, in the 20-month specimen, most of the particles were surrounded by a thin layer of newly formed bone; in the 7-year specimen there was mainly compact bone in direct contact with the particles. Under transmission electron microscopy, it was possible to characterize the bone-biomaterial interface; in the 20-month specimen an electron-dense layer was seen, whereas, almost no electron-dense lines were seen at the interface in the 7-year specimen. CONCLUSIONS: Bio-Oss particles did not interfere with bone-healing processes after sinus augmentation procedures and promoted new bone formation. This study can help clinicians to understand better the morphological characteristics of bone regeneration processes using Bio-Oss after 20 months and, most importantly, after a longer time of interaction with surrounding tissues.