A method for screening a selected material for its osteoconductive or osteoinductive potential, which includes implanting a structure comprising the material, extraskeletally into a baboon, and examining the structure a predetermined period of time after implantation to determine what amount of bone, if any, has formed on or within the structure.
An improved porous ceramic biomaterial is disclosed in which a polymer such as polylactic acid is polymerized in situ to fill the micropores substantially without filling the macropores. The polymer reinforcement helps improve the strength of the implant while preserving its ability to support ingrowth of bone to help integrate the implant into its surgical environment.
The invention relates to an osteoinductive biomaterial, which is based on a ceramic material and which has a total porosity of 20 to 90%, wherein macropores are present having a size ranging from 0.1 to 1.5 mm, and wherein micropores are present having a size ranging from 0.05 to 20 .mu.m. The invention further relates to a process for preparing said osteoinductive biomaterial.
This invention relates to a biomaterial useful in bone repair and replacement, and to implants for cranofacial, orthopaedic, and especially dental applications. The implants have a unique geometric configuration, their surfaces defining concavities having a shape and dimensions which induce or enhance the rate and/or amount of bone growth at the implant site. The biomaterial preferably has a specific porous configuration and the implant may be at least coated with such a biomaterial of hydroxyapatite, for example.
A percutaneous tissue removal apparatus having a flexible drill shaft, a cutting tip mounted on the shaft a power source for transmitting motion to the shaft to move the cutting tip against tissue and a suction source for removing tissue fragments along the shaft to a location outside the tissue mass while cutting. The apparatus may include a container for collecting one or more selected components of the harvested tissue fragments for implantation of the fragments preferably into the body of the patient from whom they were removed. Where the tissue to be cut is bone, a cutting tip is preferably made of a polymeric material which is softer than the cortical portion of the bone, although the cutting tip may be made of a ceramic or a composite material. A second flexible shaft may be provided either within or about the flexible drill shaft.
A tissue removal method utilizes a tool having a shaft with a flexible inner member rotatable about the shaft and an outer member extending along the inner member. The inner and outer members are bent to a desired configuration and the inner member rotates relative to the outer member while maintaining the shaft in the desired configuration under the influence of the rigidity of the outer member during rotation of the inner member. A patient's body tissue is cut with a cutting element connected with the inner member during rotation and the body tissue cut from the patient is moved along a passage within the shaft while the shaft is maintained in the desired configuration.