Ryan Lee (RL): I graduated from the University of Sydney, Australia (BMSc & BDent) and then completed my specialist training program in periodontology (MCD) at the Eastman Dental Institute, UCL, London. Then I came back to Australia to start my academic career, commencing a part-time PhD degree as well. In 2017, I took up a senior academic role at the School of Dentistry, the University of Queensland. Currently, I am the Director of post-graduate specialist training program and Discipline Lead in Periodontology.

RL: My passion for research into periodontology and implant dentistry began when I first attended the ITI World Symposium, New York in 2007. After listening to all those great minds in periodontology and implant dentistry, I was so inspired and decided to pursue a career in that field. Research was a big part of the post-graduate specialist training program and I was fascinated by the evidence-based approach and the different research methodologies to validate new findings. I was particularly interested in the host immune responses to different implant surfaces, resulting in different rates of osseointegration.

RL: My research topic was the investigation of the effects of different implant surface characteristics on immune cells, particularly macrophages, in diabetes. The implant surfaces we used were SLA and SLActive. It has been well documented that the SLActive surface enhances the rate of osseointegration at the early stage of osseous healing, however the underlying mechanisms were not yet fully elucidated. I was intrigued by this particular biological phenomenon, and I started asking research questions about interactions between cells involved in wound healing and different biomaterials.

The macrophage is truly a versatile immune cell that can orchestrate inflammatory responses upon its phenotype expression: pro-inflammatory M1 or anti-inflammatory M2 phenotype. Obviously, this is an over-simplification but its role in the context of wound healing is crucial. Immunomodulatory effects of macrophages and different implant surfaces are still poorly explored, especially under compromised systemic conditions, like diabetes. Hence, the aim of the study was to investigate the interactions between macrophage phenotypes (M1 and M2) and different titanium implant surfaces (SLA and SLActive) under Type 2 diabetic conditions.

RL: For the first time, the study provided empirical evidence for impaired M2 macrophage function in the wound healing process in a type 2 diabetic animal model. It showed that the modified surface (SLActive) could compensate for this impaired macrophage function by creating an environment that attenuates the inflammatory response during the early stage of osseous wound healing, hence restoring macrophage homeostasis and resulting in enhanced osseous healing.

RL: I believe this project has provided a certain insight into the interaction between biomaterials, particularly the implant surface treatment and immuno-inflammatory responses in a compromised systemic condition. As this was a pre-clinical study, it warrants further clinical studies to confirm our findings, but it has highlighted the importance of inflammation response control at the initial phase of wound healing, including osseointegration, and the biomaterials (SLActive) we use daily have the capacity to modulate the immune responses. Clinicians should decide on which materials to use while keeping this in mind.

RL: The ITI has significantly contributed to the development of implant dentistry for several decades. I believe the success of the ITI comes from its independence and strong research-oriented mindset to develop implant dentistry. Academic and financial support from this kind of organization helps many researchers/clinicians to continue with their research and provide a platform to share their achievements, ultimately shaping the future direction of implant dentistry.

RL: There is an increasing trend and emphasis on ‘personalized medicine’ in current medical research. I believe future research in dentistry will follow in the same direction. In fact, it has already started. Wound healing is an essential aspect of personalized medicine/dentistry, and host-modulation by biomaterials has been our great research interest to improve clinical outcomes. Future implant dentistry research should focus on these immuno-modulatory effects of biomaterials.

For example, in one of our projects, we are investigating the effect of enamel matrix protein on different M2 macrophage sub-phenotypes (i.e., M2a, M2b, M2c and M2d) in a diabetic model in order to incorporate the knowledge into our current understanding of wound healing. This will be further implemented into clinical management strategies in more challenging cases.