Contemporary Concepts in Osseointegration of Dental Implants: A Review

Abstract

In a society highly conscious of esthetics, prosthetic rehabilitation of lost teeth with tissue-integrated implants has gained wide acceptance and demand by patients and clinicians. The backbone of these tissue-integrated implants is the biotechnical process of osseointegration. Although the concept has been introduced and discussed for ages, the deepening knowledge about its cellular and molecular mechanisms has led the researchers to borrow further into the factors influencing the process of osseointegration. This has aided in the hastening and improving the process of osseointegration by exploiting several, even the minutest, details and events taking place in this natural process. Recently, due to the high esthetic expectations of the patients, the implants are being loaded immediately, which demands a high degree of implant stability. Implant stability, especially secondary stability, largely depends on bone formation and integration of implants to the osseous tissues. Various factors that influence the rate and success of osseointegration can either be categorized as those related to implant characteristics like the physical and chemical macro- and microdesign of implants or the bone characteristics like the amount and quality of bone and the local and systemic host conditions, or the time or protocol followed for the functional loading of the dental implant. To address the shortcomings in osseointegration due to any of the factors, it is mandatory that continuous and reliable monitoring of the status of osseointegration is done. This review attempts to encompass the mechanisms, factors affecting, and methods to assess osseointegration, followed by a discussion on the recent advances and future perspectives in dental implantology to enhance the process of osseointegration. The review was aimed at igniting the inquisitive minds to usher further the development of technology that enhances osseointegration.

Figure 1

Day 1 and day 2 after implant placement. Day 1: secretion of growth factors and migration of undifferentiated osteoblasts and pluripotent stem cells towards implant surface. Day 2: local ischemia and necrosis followed by recruitment of neutrophils and macrophages.

Figure 2

Day 3 and day 4 after implant placement. Day 3: activation of osteoblast-related transcription factors by the cells around the implant. Day 4: resorption of necrotic bone and deposition of new bone at the bone-implant interface.

Figure 3

Day 28 and 12th week after implant placement. Day 28: formation of new layer of bone adjacent to implant through contact and distant osteogenesis. End of 12th week: formation of a mature lamellar bone connection with the titanium surface.