Development of ceramic and ceramic composite devices for maxillofacial applications

Abstract

SummaryCeramic and ceramic composite materials and devices were developed for specific maxillofacial applications. These applications included: (I) Replacement of hard tissue voids in low stress areas with a phosphate-bonded alumina-foamed ceramic and a calcium aluminate-bonded alumina foam; (2) development of porous ceramic-coated metallic devices for stabilization of mandibles with avulsed segments; (3) development of implantable ceramic tooth roots onto which more or less conventional crowns may be mounted.Efforts to date have been rewarding. Using the rhesus monkey for all experimental implant work, incorporation of porous ceramic foam prostheses to eliminate maxillary defects has been accomplished. Also, we have succeeded in stabilizing the mandible where segments of from 3 to 8 mm were removed. Bridging of the gap with new bone occurred within 6 weeks resulting in a total regeneration of the resected area with restoration of normal mandibular function. Finally, implantable tooth roots were developed. Three different surface treatment techniques have been used on a basic high-density alumina core. The first is a high-density matt finish which can only permit a fibrous tissue attachment or bony approximation but no ingrowth. The second is a porous alumina coating intended to permit bone ingrowth. The third is a rough surface consisting of particles of alumina sintered to the surface to maximize the bone/ceramic interface shear strength potential. Implantations of both anterior and posterior tooth roots with all three surface configurations have been successful for periods of up to six months.

Microstructure and biomechanical characteristics of bone substitutes for trauma and orthopaedic surgery

“…With respect to pore size, microporosity ( i.e ., pores with a size < 5 μm) is considered important for the bioresorbability of the material [23], whereas macroporosity ( i.e ., pores > 100 μm) plays an important role in the osteoconductivity. A large macroporosity ( i.e ., 400-600 μm) facilitates infiltration by fibrovascular tissue and revascularization, thereby allowing for bone reconstruction.…”

Biocompatibility of materials for total joint replacement

“…Ceramic-coated metals with alumina and phosphorus glass enamels appear to be well tolerated in bone. 32 High purity carbons in different physical forms have shown very good tissue tolerance in experimental animal models in solid and particulate form33-35 and in tissue culture^.^ Among fluorocarbons, Teflon, used initially in hip prostheses, appeared well tolerated in experimental animal implantation in solid and particulate samples. Later, it proved to be locally and systemically toxic36 in the human subject.…”

Bone substitutes in the Netherlands – A systematic literature review

“…Microporosity (e.g. pores < 5 lm) is considered important for the bioresorbable properties of the material [153]. Resorption rates differ substantially between the products, mainly due to their chemical composition.…”