Premium
The use of proplast tm in otologic surgery.
Author(s) -
Shea John J.,
Homsy Charles A.
Publication year - 1974
Publication title -
the laryngoscope
Language(s) - English
Resource type - Journals
SCImago Journal Rank - 1.181
H-Index - 148
eISSN - 1531-4995
pISSN - 0023-852X
DOI - 10.1288/00005537-197410000-00014
Subject(s) - implant , materials science , elemental analysis , dentistry , composite material , biomedical engineering , surgery , medicine , chemistry , organic chemistry
The use of alloplastic implants in otolaryngologic and maxillofacial surgery has a long history. In recent years, collaborative efforts among materials scientists, surgeons, and dentists have elucidated biological and functional criteria for implant materials. Using these criteria, a new alloplastic material, Proplast TM was developed, the first of a new generation of materials for implantation, which is a composite of Teflon polymer and elemental carbon. It is very well tolerated as an interphase between metal and plastic implants and tissue. The gross physical appearance is that of a resilient black felt sponge. Because of the ingredients from which Proplast TM is made it exhibits extraordinary chemical and thermal resistance, permitting firm fusion of pieces 0.5 mm to 5 mm in thickness to metallic and rigid plastic implant materials. The resultant lamination may be sterilized by routine steam autoclave techniques used for metals. Like the elemental carbon with which it is covered, Proplast TM has the least reaction of any material known when tested in simulated biochemical exposure to pseudoextracellular fluid. The elemental carbon surface renders Proplast TM extremely wettable to body fluid, permitting precipitation of host proteins in a relatively undenatured form, camouflaging the implant from the body's immunologic rejection mechanism. Since it is 70 to 90 percent porous, Proplast TM is malleable and easily handled. It can be shaped with a knife or scissors and even shaved to a sheet 1/50th of an inch in thickness with a dermatome. Teflon and other plastics and metals suitable for implantation can be laminated to Proplast TM to form a composite alloplast with unlimited structural properties and shapes. Even though Proplast TM is relatively new to otolaryngology, it has been used extensively for the past three years in orthopedic and oral surgery as an interphase material between metal implants and surrounding tissue. These uses have demonstrated that fibrous ingrowth into the Proplast TM is rapid and acts to stabilize metal and plastic prostheses mechanically. Bound to a Teflon columella it has been successful as a Total Ossicular Replacement Prosthesis, to prevent necrosis of the drum over the malleus with a prosthesis around it, to reconstruct an atrophic retracted drum and to reconstruct the posterior canal wall. Animal experiments are now underway to determine the effect of Proplast TM on the inner ear as an oval window seal. If these are satisfactory, Proplast TM will be tried as an oval window seal around a Teflon piston inserted into a small hole in the footplate for otosclerosis.