Oral & Maxillofacial Implants and the Bone-Implant Interface

Research Overview
Oral & Maxillofacial Implants and the Bone-Implant Interface
Each year patients receive about 250,000 hip and knee implants and about 150,000 oral and maxillofacial implants. Such implants carry large loads during in vivo function. Consequently, the bone-implant interface is routinely subjected to large stresses and strains. It follows that one key design goal with load-bearing implants is to avoid damage to interfacial bone. While bone has a certain amount of reparative capacity, this capacity cannot be overwhelmed.
One of the problems is that clear danger limits for the bone-implant interface are as yet undefined. The actual mechanical properties of bone as it exists at healed-in or immediately-loaded interfaces are largely unknown. Moreover, the biological mechanisms of interfacial failure remain unclear. This lack of information translates into a largely empirical approach to commercial implant design and clinical case planning.
What is needed is an accurate database about the properties of the bone-implant interface and reliable models for predicting implant loading and stress-strain conditions at interfaces. Such data would help clinicians do better case planning, by, for example, making it possible to estimate before surgery how many implants should be used -- and where they should be placed in the mouth -- to support a bridge over the long term in a given patient having specific biting characteristics and jawbone quality. The design process could procede as follows. (In the chart, the terms "see-saw", Skalak, SBM, etc. refer to certain biomechanical models for predicting loading.) NOTE: You will have to visit this site to view the Chart.
Basic issues that arise when considering both the mechanical and biological consequences of implant loading include those listed below.
Detailed Research Topics (When visiting this site, the topics below are hyperlinked to lead you to further information)
Analytical Models for Predicting Loads on Implants
Finite Element Models for Predicting Loads on Implants
Measuring Loads on Implants in Humans
Interfacial Stress Transfer and Bonding
In Vivo Studies of Overload
Mechanisms of Overload
Loading, Bone Healing and Gene Expression