Q: Dr. Eppley, I am interested in a reversal otoplasty. I know you have used s small metal spring/clip to help hold the released ear out as an integral part of the procedure’s success. While I know that metal device works I feel uncomfortable with even a very small pieve of metal in my ear. I know you have tremendous experience with resorbable LactoSorb devices and you have probably used that in the past for a similar procedure as a spacer. In an article from 1999, it mentions the use of LactoSorb in rabbit ear cartilage where in 50 percent of the study rabbits suffered auricular skin degradation due to the thinness of the skin and tension on the wound. However it does mention that in order to decrease tissue tension at the implant site, thinner, low-profile more pliable bioresorbable plates have been designed for the nasal septum and are now available for clinical trial.” This article was from 1999 so I hope these other plates have been designed and tested. My questions is this: Would this be a concern for you in this procedure? Also would you know what the thinner, more pliable material discussed would be and if that would be a viable option as well? On a side note I bent the LactoSorb implant you let me take with me to test the pliability and with little pressure, it snapped. This could be a concern if I were to sleep on or press on the implant while healing is taking place. What are your thoughts on this matter? I would love to hear your thoughts on these questions and concerns I have.
A: In answer to your questions about the use of LactoSorb in a reversal otoplasty procedure:
- Such an animal study with that plate size is irrelevant to the human condition. In a mass to tissue ratio that would be the equivalent of putting a 2 x 4 in your arm. That is an enormous polymer load in a small tissue space. With a large load of biodegradable material per surface area of tissue I would expect to see soft tissue changes around the plate. If they really wanted to test it for ‘septal use’, they should have known to use a much smaller polymer load. Therefore, the observed concerns about plate effects on the soft tissue are both misguided and of poor scientific quality. If you want to make a comparative analogy to your clinical situation a LactoSorb device that is .1mm thick, 1mm wide and 5mm long would need to be used in such a study.
- Polymer plates stand little deformation and they will react from a biomechanical perspective like a piece of plastic. They have little room for elastic deformation when acute loading forces are placed on them. That being said, bending them between your fingers is not an analogous situation to being implanted in human tissue. In human tissue that are somewhat mechanically protected by the tissues that are attached to and they develop greater resistance to deformation through hydrophilic nature. (water absorption) However as I mentioned in the office this is a concern that is completely obviated through the use of a metal spacer technique.
Dr. Barry Eppley