Marginal Bone Loss Around the Implant: A Retrospective Analysis of Bone Remodeling Over Five Years of Follow-Up

Introduction: Bone remodeling around implants in implant-supported rehabilitation is a continuous debate with no consensus in the literature. This study aimed to investigate the implant- and patient-specific factors contributing to marginal bone loss near the implant.

Materials and methods: We included patients who had implant-supported prosthetic rehabilitation using one implant system, between 2014 and 2018, who had full follow-up documentation and orthopantomography over five years, and who had no unwell-controlled systemic pathologies that may influence bone metabolism.

Results: Eighty-one patients who received 500 implants met the inclusion criteria. We observed approximately 1 mm of bone resorption at the five-year follow-up, with the first 0.78 mm of them being documented at the three-year follow-up. Adults younger than 60 years old had an increase in bone resorption by approximately 30%. No difference was seen between men and women. However, a slight increase in bone resorption at five years was seen in female patients older than 50 years old than in ones younger than 50 years (by 30%). The narrowest diameter (3.5 mm; p = 0.001) and anterior mandible (p = 0.008) had the highest bone resorptions. Contrarily, with an insertion depth of approximately 1 mm (p = 0.004), the splinted implant prosthesis (p = 0.21) and zirconia material of the prosthesis (p = 0.57) had the lowest bone remodeling. Moreover, patients younger than 60 years and female patients above 50 years had an increased bone resorption.

Conclusions: Bone remodeling is a multifactorial process. The treatment planning has to take into consideration both implant- and patient-specific factors.