Stifle osteochondritis dissecans in snow leopards (Uncia uncia).

Three snow leopard (Uncia uncia) cubs, female and male siblings and an unrelated female, had lameness attributed to osteochondritis dissecans (OCD) lesions noted at 6, 8, and 10 mo of age, respectively. All cubs were diagnosed with OCD via radiographs. The sibling cubs both had lesions of the right lateral femoral condyles, while the unrelated cub had bilateral lesions of the lateral femoral condyles. Subsequently, OCD was confirmed in all three cases during surgical correction of the lateral femoral condyle lesions via lateral stifle arthrotomies, flap removal, and debridement of the defect sites. Histopathology also supported the diagnosis of OCD. Postoperatively, the sibling cubs developed seromas at the incision sites and mild lameness, which resolved within a month. To date, two cubs have been orthopedically sound, while one of the sibling cubs has developed mild osteoarthritis. OCD has rarely been reported in domestic felids, and to the authors' knowledge these are the first reported cases of OCD in nondomestic felids.

The effect of different titanium and hydroxyapatite-coated dental implant surfaces on phenotypic expression of human bone-derived cells.

Roughened titanium (Ti) surfaces have been widely used for dental implants. In recent years, there has been the tendency to replace Ti plasma-sprayed surfaces by sandblasted and acid-etched surfaces in order to enhance osseous apposition. Another approach has been the utilization of hydroxyapatite (HA)-coated implants. This study examines the effect of two roughened Ti dental implant surfaces on the osteoblastic phenotype of human bone-derived cells (HBDC) and compares this behavior to that for cells on an HA-coated surface. Test materials were an acid-etched and sandblasted Ti surface (Ti-DPS), a porous Ti plasma-sprayed coating (Ti-TPS), and a plasma-sprayed porous HA coating (HA). Smooth Ti machined surfaces served as control (Ti-ma). HBDC were grown on the substrata for 3, 7, 14, and 21 days, counted and probed for various bone-related mRNAs and proteins (type I collagen, osteocalcin, osteopontin, osteonectin, alkaline phosphatase, and bone sialoprotein). All dental implant surfaces significantly affected cellular growth and the temporal expression of an array of bone-related genes and proteins. HA-coated Ti had the most effect on osteoblastic differentiation inducing a greater expression of an array of osteogenic markers than recorded for cells grown on Ti-DPS and Ti-TPS, thus suggesting that the HA-coated surface may possess a higher potency to enhance osteogenesis. Furthermore, Ti-DPS surfaces induced greater osteoblast proliferation and differentiation than Ti-TPS.

The effect of bioactive glass ceramics on the expression of bone-related genes and proteins in vitro.

Using biodegradable bone substitutes in alveolar ridge augmentation avoids second-site surgery for autograft harvesting. Considerable efforts have been undertaken to develop rapidly resorbable bone substitute materials with a higher degree of biodegradability than tricalcium phosphate (TCP). This study examines the effect of novel biodegradable glass ceramics on the expression of bone-related genes and proteins by human bone-derived cells (HBDC) and compares this behavior with that of TCP. Test materials used were alpha-TCP, a surface-treated glass ceramic GB9N with crystalline phase Ca(2)KNa(PO(4))(2) and a small amount of amorphous silica phosphate; AP40 - a glass ceramic based on crystalline phases of apatite and wollastonite; and a glass ceramic Mg5 composed of 20.6% CaO, 58.5% P(2)O(5), 14.4% Na(2)O, 4.1% MgO and 2.4% CaF(2) (wt%). HBDC were grown on the substrata for 3, 5, 7, 14 and 21 days, counted and probed for various bone-related mRNAs and proteins (type I collagen (Col I), osteocalcin (OC), osteopontin (OP), osteonectin (ON), alkaline phosphatase (ALP) and bone sialoprotein (BSP)). The substrata supported continuous cellular growth for 21 days. By day 21, GB9N had the highest number of HBDC. GB9N induced significantly enhanced expression of Col I, ALP, OP, OC and ON mRNA at 3 days; of OP, OC and ON mRNA and protein at 7 and 14 days; and of ALP, OP and OC mRNA and Col I, ALP, BSP, ON and OP protein at 21 days. Since all novel glass ceramics supported cellular proliferation together with expression of bone-related genes and proteins at least as much as TCP, these ceramics can be regarded as potential bone substitutes. GB9N had the most effect on osteoblastic differentiation, thus suggesting that this material may possess a higher potency to enhance osteogenesis than TCP.