Comparative evaluation of bone density changes around root-form, threaded collar, two-piece endosseous implants at three different levels as influenced by early loading and conventional loading protocols using cone-beam computed tomography

Abstract

Background: Understanding the changes in bone density after insertion of dental implants and their relation to immediate/early loading is essential to achieving improvements in their survival rate. Histological investigations of the bone bed in humans are limited, which in turn hampers opportunities to deepen knowledge about the remodeling process around dental implants. Purpose: The aim of this pilot study was to comparatively evaluate the bone density changes around root-form, threaded collar, two-piece endosseous implants at three different levels as influenced by early and conventional protocols using cone-beam computed tomography (CBCT). Methodology: Twenty implants were placed in 20 patients who were randomly assigned to two groups. Group A (n = 10 implants, 10 patients) received conventional loading protocol and Group B (n = 10 implants, 10 patients) followed early loading protocol following implant placement. Bone density changes were evaluated and compared as influenced by early and conventional protocols using CBCT (gray values). The gray values were measured at the apical level, middle region of radiological implant length, and at the crestal level. The measurements were made immediately (T0) and 36 weeks (T1) post implant placement. Results: Intergroup comparison of bone density changes was done between Group A (conventional loading) and Group B (early loading) from immediate post implant placement to 36 weeks post implant placement follow-up. From immediate post implant placement to follow-up, significant difference was seen in bone density of Group A and Group B at apical and middle levels as P < 0.05, but at crestal level, no significant difference was seen. Conclusion: Under the conditions of this study, early loading significantly densified more bone as compared to conventional loading. Further studies are required to determine CBCT gray values and its correlation with computed tomography Hounsfield units for quantification of the bone.