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PubMed1978

Freeze-dried allogeneic segmental cortical-bone grafts in dogs.

Forty-four adult male mongrel dogs were used to compare segmental cortical freeze-dried allogeneic bone grafts with fresh autogenous, freeze-dried autogenous, and fresh allogeneic segmental cortical grafts. Group I consisted of bilateral fresh autografts as external controls; Group II, a fresh autograft on one side for internal control and a freeze-dried autogenous graft on the other side to evaluate the effect of freeze-drying on repair; Group III, a fresh autograft on one side and a fresh allograft on the other side to measure the differences between autogenous and allogeneic grafts; and Group IV, a fresh autograft on one side and a freeze-dried allogeneic graft on the other to see if freeze-drying altered the repair of allogeneic grafts. The grafts were analyzed qualitatively over a six-month period by the use of interval roentgenograms to determine the times of graft-host union and the incidence of fatigue fractures. Six months after operation, the repair processes in the four groups were compared quantitatively with respect to biological repair and physical strength using torsional stress-testing, tetracycline labeling, and microradiography. The results indicate both qualitatively and quantitatively that: (1) fresh bilateral segmental cortical autografts show reproducible characteristics, so that the canine fibula furnishes a satisfactory model (Group I); (2) freeze-drying does not inhibit the repair process per se (Group II); (3) fresh allografts are rejected in varying degrees of intensity (Group III); and (4) freeze-drying does not protect cortical allogeneic grafts from such rejection (Group IV).

Animals↗

PubMed1986

Boiled and unboiled detached autogenous bone fragments--an experimental study.

Boiled and unboiled standardized detached bone fragments were compared in a canine model. The fragments were either left detached or fixed with a lag-screw. Additionally, various replacements were combined with transverse osteotomy followed by reduction and fixation with a six-hole neutralization plate based on the AO-principle. Follow-up was at 0-6 weeks, 6-12 weeks and 12-24 weeks. Examination of the specimens comprised radiology, histology, microradiography, fluorescence-microscopy and microangiography. Qualitative assessment indicated that boiled bone showed some delay in resorption and new bone formation when compared with unboiled bone after six weeks, but this difference was no longer discernible after 12 weeks. Semi-quantitative assessment revealed hardly any difference after six weeks. During the first few weeks, however, boiled fragments showed a clear delay of 10-14 days in resorption and new bone formation when compared with unboiled fragments. The clinical relevance is that detached bone fragments contaminated with street-refuse can be sterilized by boiling without harmful effects. Replacement of the boiled bone fragments shows a somewhat delayed, but otherwise normal resorption and new bone formation.

Animals↗

PubMed1985

Feline model for the study of frozen osteoarticular hemijoint transplantation: qualitative and quantitative assessment of bone healing.

Twenty-four outbred cats underwent massive osteoarticular allograft and control autograft transplantation, using the right distal femur with its articular cartilage, capsule, and medial collateral ligament intact. The cats were monitored clinically and radiographically for 1 year. Groups of cats (4 allografts and 2 control autografts) were euthanatized at 3-, 6-, 9-, and 12-month intervals. At necropsy, the grafts were photographed and assessed for bone healing and replacement by standard radiography, quantitative 99mTc bone scans, microradiography, and histologic examination of decalcified and nondecalcified specimens. The osteosynthesis site of the allografts usually healed by 5 months, compared with the autografts that healed by 3 months. As illustrated by quantitative bone scans, creeping appositional new bone slowly invaded and replaced the allograft bone. Seemingly, the cat can be used as an acceptable and clinically comparable model for the massive osteoarticular allografts currently being used for the reconstruction of joints damaged or destroyed by neoplasm surgery in limb-sparing procedures in human beings. This model may also be used to assess the rate and method of bone healing.

Animals↗

PubMed1986

Topography and differential growth of the nasal ventral concha (os conchae nasalis ventralis) of the pig from birth to six weeks of age.

To study the growth of nasal ventral concha (os conchae nasalis ventralis) of pigs between birth and 6 weeks of age, 7 undecalcified 80-micron thick nasal cross sections between the 3rd incisor and the 3rd premolar teeth were examined by microradiography and fluorescence microscopy, after labeling with tetracycline and alizarine red S. Conchal growth was particularly rapid in the pigs during the first 2 weeks of life. From the 3rd week, growth of the nasal ventral concha became slower. For a given age, the slow growing zone spread in the rostrocaudal direction. The transversely directed growth of the nasal ventral concha resulted in the optimal filling of the nasal cavities.

Aging↗

PubMedDate not supplied

Bioresorption of ceramic strontium-85-labeled calcium phosphate implants in dog femora. A pilot study to quantitate bioresorption of ceramic implants of hydroxyapatite and tricalcium orthophosphate in vivo.

Ceramic hydroxyapatite and tricalcium orthophosphate were radioactively labeled with their strontium-85 analogs. Porous blocks of these materials (dimensions 2.5 X 1.25 X 0.5 cm) were implanted into surgically created defects in dog femora. The fate of the implants was studied by roentgenography, radioactivity measurements, histology, and microradiography. The radioactivity over the implant site was followed for 22 weeks. Implants were retrieved after 20-25 and 50-55 weeks. Hydroxyapatite implants were not affected by biodegradation processes, while tricalcium orthophosphate implants were subject to extensive bioresorption (25%-30% in 22 weeks). Resorption debris from tricalcium orthophosphate implants was found in mononuclear phagocytes and multinuclear osteoclastlike cells. The supposition is that tricalcium orthophosphate is transformed into hydroxyapatite in a physiologic environment. Labeling of ceramic calcium phosphate implants with strontium-85 analogs offers an adequate technique to quantitate bioresorption in vivo.

Animals↗

PubMed1979

Osteogenesis by periosteal transplant. Experimental study of spinal fusion in rats.

Autogenous transplantation of periosteum was performed in 60 rats. Periosteum was transferred from the femur to the spinal column in the region of thoracic vertebra 8 to lumbar vertebra 2. Follow-up included histological examination and microradiography. New bone formation occurred late and the bones were of a heterotopic nature; a solid arthrodesis was not achieved. Free periosteal grafts do not exhibit the relatively predictable behavior of periosteal flaps. Greater understanding at the biomolecular level may be required before free periosteal grafts can be introduced into routine clinical practice.

Animals↗

PubMed1979

Experimental traumatic cataract. I. A quantitative microradiographic study.

Traumatic cataract was induced in rat and rabbit. The progression of the posterior subcapsular cataract and the wound healing were followed by quantitative microradiography. This method makes it possible to determine the dry mass content and to calculate the refractive indices in the lens. In the injured rat lens a reduced dry mass concentration was determined in both the wound region and the posterior subcapsular region immediately after trauma. During the first week a subcapsular opacity was observed to enlarge. This opacification always corresponded to a reduction in the subcapsular concentration of dry mass. This reduced content of dry material, mainly consisting of protein, is interpreted as a hydration of the subcapsular cortex. In the rabbit lens a much larger injury had to be made in order to cause any posterior cataract. The same reduction in the content of dry material was determined in regions corresponding to opacitices but the reduction was less pronounced than in the rat lens. The border zones between different concentrations of dry mass are suggested to be the main sources of scattered light in the traumatic cataract.

Animals↗

PubMed1977

[Comparative study of bone mineral densities in the human skeleton].

The different mineral densities and their distribution within human bone of the iliac crest, the femoral and the humeral head are analysed by microradiography with computerized photometry. 10 male and 11 female corpses between the age of 17 to 80, show that the results obtained depended upon age, sex and upon the site of the bone biopsy. Bcause of the small number of cases in this preliminary investigation, careful interpretation of these differences is mandatory. The advantages of this method are discussed.

Adolescent↗

PubMed1983

[Rational preparation of thin bone sections by mechanical grinding. I. Method].

A grinding machine for preparing thin nondecalcified bone sections after methacrylate embedding is described. A second micrometer screw with diamond is mounted in a specimen holder to adjust exactly the final thickness of the sections. The bone specimens are ground by a turnably mounted rough glass plate. The desired thickness of the sections is reached as soon as the diamond tip of the micrometer screw touches the glass surface. The sections can are used for microradiography, fluorescence microscopy, and histochemical investigations.

Bone and Bones↗

PubMed1978

Bovine dental fluorosis: histologic and physical characteristics.

Incisor teeth from 5- to 6-year-old Holstein-Friesian cattle maintained on a ration averaging 40 ppm F annually from 4 months of age were analyzed by a variety of histologic techniques. These techniques included photomicroscopy, microradiography, protein staining, and microhardness testing. The features of fluorotic enamel that were noted were: hypomineralized outer enamel, coronal cementum hyperplasia, disrupted subsurface pigment band, hypoplastic pits, puckered incremental lines, periodic radiolucent regions, positive protein staining, and decreased microhardness of the outer enamel. These results were similar to the lesions of dental fluorosis observed in other species, and explain the external appearance of fluorotic bovine teeth observed under field conditions.

Animals↗

PubMed1984

Bone changes after alcohol abuse.

In this study bone morphometric findings in 19 heavy or moderate drinkers are compared with those in 43 non-drinkers (22 non-osteoporotic patients with osteo-arthritis (OA) and 21 osteoporotic patients with femoral neck fractures (FNFs). Transiliac bone biopsy specimens were examined for assessment of trabecular bone volume and thickness, bone resorption and formation, osteoid seam length and width and the mineralization front by quantitative histomorphometry and microradiography. Trabecular bone volume and thickness were significantly diminished in the drinking group when compared with those in the 22 non-drinking patients with OA (P less than 0,005 and P less than 0,0001 respectively). Bone formation was significantly lower in the drinkers than in the OA group (P less than 0,0005), and bone resorption was significantly greater in the drinkers than in the OA (P less than 0,005) and FNF (P less than 0,01) groups. In heavy drinkers bone formation was significantly lower (P less than 0,05) than in moderate drinkers. The extent of the mineralization front was significantly lower in the drinking group than in the OA (P less than 0,005) and FNF (P less than 0,0005) groups. Osteoid seam length and width did not differ in the three groups. The presence of abnormal liver function test results did not significantly affect any of the parameters. It is concluded that alcohol abuse is associated with: (i) uncoupling of bone resorption and bone formation; (ii) reduced trabecular bone volume and thickness; and (iii) a mild mineralization defect.

Adult↗

PubMed1983

[Histological studies of the effect of intra-operative irradiation on osteosarcoma].

At the Department of Orthopaedic Surgery of Kyoto University Hospital, intra-operative radiotherapy by the high dose electron irradiation has so far been used in treating patients with osteosarcoma. The dose distribution was calculated by CT-number so that the focus was subject to at least 80% of the irradiation doses and the surgically opened lesion was irradiated with 5,000 rad of 12-26 MeV electron beams. In order to accurately assess its therapeutic effect, histological studies were conducted on 9 patients who underwent en bloc resection or amputation following irradiation treatment for osteosarcoma. Method The excised specimen was sagittally cut in half and was fixed in 10% neutral buffered formalin. The specimen was cut into 5 mm thick sections corresponding to CT cross sections. At the border region between irradiated and non-irradiated fields, specimens were prepared using sagittal sections to compare the histological findings of both fields. After all specimens were carefully macroscopically examined and then photographed with soft-X-ray film, some of them were prepared as non- delimed specimens in polyester resin and were observed by contact microradiography and fluorescent microscopy. The remaining specimens after deliming in Plank - Rychlo solution were sliced to 4-8 micron thick for study as large specimen stained with hematoxylin and eosin. Four patients had been administered tetracycline 3 days preoperatively. Results Histologically the changes of the specimens were evaluated using the Oohoshi and Shimosato 's criteria for the histological effects of irradiation. In two of the 9 patients, who had received unidirectional irradiation, the survival of Grade 2a-2b tumor tissue was observed in the superficial layers both inside and outside the periosteum. Six patients who were irradiated from both sides or three directions, showed complete necrosis in extremely small areas of Grade 2b-3 change of tumor cells. Only one of these 9 patients had a local recurrence after the irradiation. Marked fluorescence was observed in the recurrent tissue by tetracycline labeling, but no fluorescence was observed in any of the other cases in the tumorous tissues which had fallen within the range of irradiation. These findings strongly suggest that intra-operative irradiation is extremely effective in controlling local osteosarcoma lesion in the extremities.

Adolescent↗

PubMed1983

Metallic debris arising from prosthetic abrasion: investigation of biodegradation of the materials and physiopathology of the bone.

The authors investigated the tissue around a failed knee prosthesis which had a metal-on-metal bearing made of chromium-cobalt-molybdenum alloy. Histological examination and the quantitative analysis of metallic particles found in the bone marrow (by fluorescent spectrometry and laser microsound) provided a detailed picture of the quantity, nature and distribution of the wear debris. The type and nature of the tissue response to the presence of the metal particles was determined by fluorescent microscopy and microradiography.

Aged↗

PubMed1980

[Study on the setting reaction of the zinc phosphate dental cement (1). Effects of aluminum in liquid on setting reaction (author's transl)].

The liquid of zinc phosphate dental cement contains Al3+ and Zn2+, and these ions effect greatly on the setting reaction of the cement. When zinc oxide powder is mixed with this cement liquid, reaction products in the set cement are amorphous and not made sure by X-ray diffraction. Therefore the setting reaction of zinc phosphate cement is not certain. In this paper the effects of Al3+ on the setting reaction of cement are examined by X-ray diffraction, thermal analysis and infrared spectrum, and set cements are observed by SEM and microradiography. Judging from these results, it is conclude that Al3+ in the cement liquid precipitates amorphous aluminium phosphate due to change of pH of liquid when it is mixed with zinc oxide powder.

Aluminum↗

PubMed1982

The response of the lens to trauma.

The results of a number of investigations into traumatic cataract and after-cataract are presented. The traumatic cataract has been studied both in human lenses and experimentally. Light and electron microscopy, quantitative microradiography and an extracellular tracer--procion dye, were used to follow the cellular changes during cataract progression. The influence of wound size and wound healing as well as the lens fibre response to trauma were followed. Furthermore, tissue culture was used to study the proliferation of lens epithelial cells on the lens capsule. The after-cataract formed in tissue culture as well as experimental traumatic cataracts in rats and rabbits were compared to different stages of human traumatic cataract. Traumatic cataract has a subcapsular distribution and the importance of an intact functioning epithelium for lens transparency is emphasized.

Animals↗

PubMed1982

Osteosclerosis in leprosy.

The literature contains little reference to the phenomenon of osteosclerosis in leprosy. The aim of the authors' investigations was to determine: a) the incidence of osteosclerosis as part of the radiographic picture in the distal extremities of the limbs; b) the pathological substratum; c) the possible clinical significance. The research was carried out on 233 leprosy patients at the Colonia Hanseniana di Gioia del Colle (Bari). The authors examined 260 radiographs of the hands and 1310 radiographs of the feet. A number of biopsy samples of bone were taken from four patients and examined by means of microradiography using ultraviolet fluorescent light and also by historadiography. The basic radiographic features indicative of osteosclerosis were: a) reactive osteosclerosis; b) sclerosing periostosis; c) massive osteosclerosis. The authors observed a preponderance of osteosclerosis in the bones of the first digital ray, both in the phalanges and metatarsals or metacarpals. The sesamoid bones were affected more commonly in those of the first digit than those of the fifth. The radiographic findings were confirmed microscopically. It is difficult to assess the possible clinical significance because of the transient nature of the osteosclerosis in the evolution of the lepromatous lesions with time.

Adult↗

PubMed1981

Inhibitory effect on bone formation and calcification exerted by the anti-inflammatory drug ibuprofen. An experimental study on adult rat with fracture.

The anti-inflammatory drug ibuprofen (2-(4-isobutylfenyl)propionic acid) was administered to adult male rats for 10 weeks in daily oral doses of 16 mg. Fractured and unfractured tibias were studied during 4 to 10 weeks' treatment by the use of microradiography, fluorescence labelling and biochemistry. New bone formation was observed to be inhibited on endosteal surfaces of the tibia when treated with ibuprofen, which also diminished the amount of cortical bone (almost significantly). However, the bone area and the new bone formation of periosteal callus and on periosteal surfaces of tibia was not influenced by the treatment. The chemical composition of fractured and unfractured bone was significantly altered and showed a reduced ratio of hydroxyproline/nitrogen as well as an inhibition of calcification of bone matrix with a reduced calcium/nitrogen ratio followed by an increased ratio of hexosamine/DNA and RNA-ribose/DNA after treatment with ibuprofen. The inhibition of new bone formation and calcification of bone in adult rat exerted by ibuprofen may be explained as a direct effect on bone-forming cells on endosteal bone surfaces.

Animals↗

PubMed1980

The relationship of bone blood flow, bone tracer deposition, and endosteal new bone formation.

Bilateral defects of 4.5 by 11 mm were made in the distal one-third of the tibias of eight dogs and unilaterally in four dogs. Bone blood flow was measured by I-Ap washout, tracer deposition of 85Sr was determined, and extraction of 85Sr and [14C]sucrose was measured by the indicator-dilution technique. Endosteal new bone formation was determined by a combined tetracycline-microradiography method. There was a significant correlation between blood flow determined by washout (I-Ap determined over the area of healing bone) and endosteal new bone formation, p < 0.001, expressed as relationships (percent) of the area of new endosteal bone to the total area enclosed by the defect and the medullary cavity of the tibia, p < 0.001. This percentage ranged from 12% to 62% and was directly related to bone blood flow. This suggests that the increase in blood flow in new bone may be secondary to increased metabolic demands.

Animals↗