Resorption rates of 2 commercially available bioresorbable membranes

Abstract

The respective resorption rates of recently commercialized collagen versus polylactic acid-citric acid ester membranes were compared. 16 rabbits were implanted with 2 mm x 4 mm pieces of membrane of both types in the alveolar mucosa just apically to the incisors on either side of the mouth. 1 animal was sacrificed on day 0, just after the operation. The others were sacrificed at 1, 2, 3, 5, 7, 9 and 12 weeks. The specimens were prepared for histologic examination. Observations showed that the cross-linked collagen membranes induced severe inflammation and were resorbed within 2 weeks. The polylactic acid-citric acid ester polymer barriers produced a much more moderate infiltrate and were still not totally resorbed at 12 weeks. Although resorption rates in the rabbit may not be similar to those observed in humans, it seems that the durability of the polymer barrier is more adequate for guided tissue regeneration than the cross-linked collagen.

Use of Collagen, PTFE and PRF Membranes in Bone Reconstruction an Experimental and Histomorphometric Study

“…6) (23)(24)(25) Resorbable membranes are easier to use, but we cannot manage the time of their resorption and the effect that degradation has on the bone formation. (26,27) The most important collagen membrane is BioGuide. It is a porcine collagen type I membrane, with a bilaminar structure, one dense layer and one porous layer.…”

Poly-D-L-Lactic Acid Membranes for Bone Regeneration

“…PDLLA membranes and pins were not visible in the specimens, but the empty spaces left by such devices after the histologic processing were evident (Figs. [6][7][8][9]. A close contact between the PDLLA devices and the surrounding bone was always found, and no traces of inflammatory tissue or signs of infection were detected.…”

“…Nevertheless, such membranes showed to be in some case less effective than the nonresorbable ones, due to their reduced mechanical properties and to a decreased barrier function, as a result of the rapid enzymatic degradation by macrophages and polymorphonuclear leukocytes. 9 A 50% mix of poly-D-lactide acid and poly-L-lactide acid (PDLLA) has been developed in 2007 with the aim to produce resorbable devices with high biocompatibility, extended resorption time, and increased mechanical properties. 10,11 Such material has been proposed in the form of resorbable mesh, membranes, foils, and pins for osteosynthesis procedures, finding application especially in the field of neuro surgery and maxillofacial surgery, with encouraging results.…”

Reparação ao redor de implantes de titânio após regeneração óssea guiada com membrana reabsorvível

“…Em um estudo em coelhos, Miller et al (1996) observaram um íntimo contato dos tecidos circunjacentes com a membrana e um marcante coágulo sanguíneo. Sendo assim, constatou-se a adaptação da membrana às estruturas anatômicas vizinhas, indicando uma pré-disposição para ocorrer a interação com esses tecidos.…”

“…Estudos mostraram que a remoção precoce da membrana resultou na formação reduzida de osso e preenchimento incompleto por este tecido (Becker et al, 1994;Lekholm et al, 1993). Apesar das membranas de colágeno apresentaremse biocompatíveis, elas possuem propriedades mecânicas desfavoráveis (Hurzeler et al, 1998) e função de barreira inadequada, devido a sua rápida biodegradação pela atividade enzimática dos macrófagos e leucócitos polimorfonucleares (Miller et al, 1996;Zzhao et al, 2000;Owens;Yukna, 2001). Estudos clínicos (Zitzmann et al, 1997;Lang, 2001) demonstraram que membranas, utilizadas para ROG, devem permanecer por mais tempo que membranas utilizadas para regeneração tecidual guiada (RTG).…”