Dr. Chen, you are an expert on bone regeneration, a pretty big topic. If you could describe in two words what it means to you, they would be:
Dr. Chen: For sure regeneration and structure.
What do you think are the typical complications in bone regeneration?
Dr. Chen: I think we can divide the complications into two main categories: those resulting from severe complications such as infections, which lead to partial or total failure of the procedure, or complications resulting from insufficient augmentation procedure with reduced amount of bone regeneration.
What should a bone substitute guarantee first?
Dr. Chen: Osteoinduction and osteoconduction. Possibly both properties together (laughs)! Then of course it depends on the purpose for which you want to use the bone substitute. For example, if I want to reconstruct the contour of the anterior maxilla, I need a substitute with a slow rate of degradation. If I want to reconstruct severe vertical bone defects, it would be great to have a highly osteoinductive material besides the osteoconductive and scaffold property.
What are the major changes you have seen in the last decade in the field of bone regeneration?
Dr. Chen: I think there have been two major changes. First, the availability and reliability of bone regeneration treatments with well documented bone substitutes have consequently broadened the spectrum of possible indications for implantation. Secondly, education and training for young researchers and clinicians have increased significantly. Now I think it is the era when regeneration treatments are driven by customized and smart techniques.
In this regard, what is your opinion about 3D printing?
Dr. Chen: I think it is one of the trends of the future. It is now clear that pre-designed and pre-fabricated 3D shaped bone grafts are better suited to the defect than traditional devices, especially in cases with severe bone deficiency. Of course, what I hope to see soon on the market are 3D materials that already have osteoinduction and osteoconduction properties. It is very challenging, but it would greatly simplify the treatment of large defects for which a high regeneration potential is required.
How to mix autologous bone and bone substitute seems to be a controversial topic. What about your experience?
Dr. Chen: There are many publications that have evaluated different ratios and they have shown that the presence of autologous bone accelerates bone formation, preferably with the ratio of 1:1. From my own experience, I try to use a 1:1 ratio or a bias toward the bone substitute with low resorption rate, for the simple reason that I prefer to harvest autologous bone from neighboring areas to those of the surgery, avoiding as much as possible additional surgery and further morbidity for the patient. Sometimes I even use the bone substitute alone. Preserving bone volume is a requirement that I think is very important for long-term stability.
This year in Barcelona, for the first time a Chinese speaker appears in the scientific program of the International Osteology Symposium. Could you share with us your feelings?
Dr. Chen: It has been a real honor for me to be able to attend this event, share and communicate with colleagues from different parts of the world. I felt a great responsibility to come to Barcelona as a door opener and a representative for China. We have learnt and are learning a lot from the pioneers of the Western world and now in China there are very brilliant and talented researchers. I hope one day to see them on the podium too!
First you graduated and now you teach young researchers at Peking University, the university that every Chinese student dreams of. What advice would you give to them?
Dr. Chen: Personally, I'm very lucky. I've always enjoyed what I have done, and I have never felt like I was competing with others. And I believe that my attitude and passion for what I do is passed on to my students. We don't have enough time to teach them everything they need from a technical point of view, so I always try to compensate by helping them understand which path they really want to take. I believe that this more philosophical approach can be of great help!
Thank you, Dr. Chen, for the interesting interview.