Reconstructed eardrum

Six years after Dr. Grisotto had begun to carry out tests on humans, the number of patients studied in the hospitals of Ribeirão, Itajobi, Juiz de Fora and others had reached 3,000 of whom 2,500 had ulcers and the remainder with a perforated eardrum by infection or trauma. All of the tests were carried out after approval by the Medical Ethics Commission of the respective institutions.

The surgeries to reconstitute the eardrum using a biomembrane of latex were carried out at the Otolaryngology Sector of the Ophthalmology and Otolaryngology Department of FMRP. This surgery, named myringoplasty, has as its objective the reconstitution of the mechanism of sound transmission. Various materials are used for this objective, a favorite being the fascia (a layer of fibrous tissue that covers the body under the skin) of temporal muscle, cartilage, placental tissue, among others, but the results showed up to 30% of failure from the anatomic point of view and 19% of re-perforation mainly caused by the lack of blood vessels in the graft.

On the other hand, the use of a biomembrane from latex showed intense vascularization, as indicated in the work of the otolaryngologists José Antonio Apparecido de Oliveira and Miguel Angelo Hyppolito from USP at Ribeirão Preto named "Myringoplasty Making Use of a New Biosynthetic Material", presented in 1998 during the 34th Brazilian Congress of Otolaryngology in Porto Alegre. The team won first place by describing the success of the grafts using the biopolymer. "We verified intense vascularization in 100% of the grafts, which is not usual when not using a membrane made from natural latex", states one of the parts of the prize-winning paper. The report refers to only nineteen perforated eardrums that received the biomaterial as a transitory implant during myringoplasty. Today the number of successes has reached five hundred.

Two doctorate theses, developed at the Surgery and Anatomy Department of FMRP, under the guidance of Professors Jesualdo Cherri and Carlos Eli Piccinato, and defended by the vascular surgeons Mário Augusto da Silva Freitas and Paulo Cesar Grisotto, respectively in August of 2001 and February of 2003, have pointed out, after tests done with animals, that it is possible to recover cardiovascular arteries by way of the use of latex prostheses. But as yet more experimental work is necessary before making tests on human patients, in order to evaluate the efficiency of this material that could substitute the current synthetic prosthesis or biological material of animal origin, such as the pericardium of the cow or pig.

These pieces of research show that the biopolymer based on vegetal latex could still give origin to many other products, with diverse applications. The dressings are only the first step for the company Pele Nova Biotecnologia to enter into dispute for a national market estimated at around 4.5 million people, who, most probably, could not pay the very high cost for the imported medicine.