Bone induction by composite of bioerodible polyorthoester and demineralized bone matrix in rats

Fracture healing in rats inhibited by locally administered indomethacin

“…Because the polyorthoester may delay, but not inhibit, heterotopic and orthotopic bone formation (Sudmann et al 1990, Pinholt et al 1991, Solheim et al 1992, these results support the contention that the direct local effect of indomethacin is the important one (Sudmann et al 1979).…”

Growth factors in bone

“…Fibrin-collagen paste and fibrin sealant were incompletely absorbed, induced a chronic inflammation and inhibited heterotopic osteoinduction [52,61]. We have evaluated the effect of a bioerodible polyorthoester made for sustained delivery on heterotopic [51,61] and orthotopic [59,60,63] osteogenesis. The polyorthoester does not inhibit bone formation, it induces little tissue reaction and it is mostly resorbed by 4 weeks.…”

“…Several biodegradable materials have been investigated, including (1) organic materials such as inactive demineralized bone proteins, collagen, fibrin sealant, fibrin-collagen paste, squalene and glycerol; (2) ceramics, including β-tricalcium phosphate and plaster of Paris (calcium sulphate); and (3) synthetic polymers such as polylactic acid [42], polyactide-polyglycolide co-polymer [56], polyanhydride [43] and polyorthoester [51,61].…”

Assessment in rats of a new bioerodible bone-wax-like polymer

“…Finally, since the polyorthoester may release a drug of choice at a predictable rate (Capozza et al 1978, Heller et al 19811, unlike beeswax, it can be used as a local. sustained drug release system, e.g., for antibiotics, antiinflammatory drugs and bone-inducing substances (Pinholt et al 1991, Engesrttter et al 1992, Solheim et al 1992. These polymers thus seem promising as a resorbable device, a hemostatic sealant, and as a vehicle for drugs in bone surgery.…”

“…The hemostatic effect was as effective as using beeswax. Platelets play an important role in normal hemostasis, but the polyorthoester does not promote platelet aggregation (Solheim et al 1991). …”