oxytetracycline--anhydrous and alizarin

The objective of this study was to determine if variation in the shape and mineralization of the mandibular condyle are the result of natural adaptation in response to different functional loading demands. Eight female Kuni Kuni piglets were randomly assigned to two groups of four, receiving either a soft or hard diet. Each animal was given three separate doses of vital stains intravenously at set time points during the study. At 8.5 months, animals were euthanized and temporomandibular joints (TMJs) were excised. Histological analysis was used to measure the amount of new bone deposition in the anterior, central, and posterior regions of the mandibular condyle. Backscatter electron (BSE) imaging was used as a semiquantitative estimate of bone mineralization in these two diet groups. Histology revealed that the degree of new bone deposition in the hard-diet group was significantly (n = 4, P < 0.001, paired t-test) higher than that of the soft-diet group. Also, the majority (87%) of animals fed a hard diet tended to show greater new bone deposition on the leftside in comparison to the right, indicating a chewing preference for the left side. In both groups, the degree of new bone deposition was significantly (P < 0.01) higher in the posterior area than in other regions. BSE imaging corroborated basic histology results, with significantly (P < 0.01) higher mineralization levels detected in the hard-diet group. These findings indicate that diet consistency has a small but significant effect on the rate of bone deposition in the mandibular condyle.

Topics: Animal Feed; Animals; Anthraquinones; Biomarkers; Calcification, Physiologic; Female; Mandibular Condyle; Mastication; Masticatory Muscles; Oxytetracycline; Swine; Swine, Miniature

An experiment was designed to investigate whether systemic administration of tetracyclines (TCs) as bone fluorochrome labels could interfere with bone modeling in vivo and inhibit osteoclast formation and activity in vitro. Cell cultures of rat bone marrow macrophages revealed that TC and oxytetracycline inhibited osteoclastogenesis and bone resorption and stimulated apoptosis. Forty rats in five groups were treated with saline, calcein green, alizarin red S, TC, or oxytetracycline. Their tibias were used for histomorphometric analysis, including bone static, dynamic, and resorption parameters in the tibial proximal metaphysis. No significant differences in bone volume per tissue volume, trabecular number, trabecular thickness, trabecular separation, bone formation rate per bone surface, mineralizing surface, or mineral apposition rate were observed. TC or oxytetracycline decreased eroded surface, number of osteoclasts per bone perimeter, and osteoclast surface per bone surface by about 50%. The results demonstrated that TC and oxytetracycline inhibit rat osteoclast formation and activity in vitro, and histomorphometric parameters involved in bone turnover may be affected by the use of oxytetracycline and TC as fluorescent bone labels in vivo.

Topics: Age Factors; Animals; Anthraquinones; Anti-Bacterial Agents; Bone and Bones; Bone Density Conservation Agents; Bone Remodeling; Bone Resorption; Cells, Cultured; Fluoresceins; Osteoclasts; Oxytetracycline; Rats; Staining and Labeling; Stem Cells; Tetracyclines

To investigate the biologic effects of Corticision on alveolar remodeling in orthodontic tooth movement.. In this study, 16 cats were divided into 3 groups: group A, only orthodontic force (control); group B, orthodontic force plus Corticision; and group C, orthodontic force plus Corticision and periodic mobilization. Histologic and histomorphometric studies were performed on tissue specimens on days 7, 14, 21, and 28.. Extensive direct resorption of bundle bone with less hyalinization and more rapid removal of hyalinized tissue were observed in group B. The accumulated mean apposition area of new bone on day 28 was observed to be 3.5-fold higher in group B than in the control group A.. Corticision might be an efficient procedure for accelerating orthodontic tooth movement accompanied with alveolar bone remodeling.

Topics: Alveolar Process; Animals; Anthraquinones; Bone Marrow; Bone Remodeling; Bone Resorption; Cats; Cuspid; Fluoresceins; Fluorescent Dyes; Hyalin; Male; Osteoblasts; Osteoclasts; Osteogenesis; Oxytetracycline; Periodontal Ligament; Stress, Mechanical; Time Factors; Tooth Movement Techniques

Injectable calcium phosphate hydraulic cements (CPHC) are a new family of bone substitutes within the class of bone reconstruction biomaterials. In this work, CPHC were tested in two consistencies (preset blocks or liquid paste) in an experimental model of cancellous bone defect in sheep. The defects were eight times larger than those investigated previously in rabbits. Three delays (12, 24, and 52 weeks) were used. Before death, a double label of oxytetracycline and alizarine was made intravenously. The distribution of implants was randomized, histomorphometric evaluation was performed and compared with micrographic observation, and optical microscopy of stained sections was performed either under visible, ultraviolet, or polarized light. The results were compared with spontaneous healing of empty defects and with a control group of normal cancellous bone from sheeps of the same age. No significant difference has been observed between premolded and injected implants. In the sheep model, the degradation and new bone formation rates are three times slower, compared with those observed previously in rabbits. New bone formation increased from 5.9% (12 weeks) up to 11.0% (24 weeks) in the empty defect group. In the cement groups, 28.3% new bone was obtained at 12 weeks, which seemed then to level off (27.8% new bone at 24 weeks). Cement residues appear as radio-opaque cylinders on microradiographs. In all cases, a radiolucent layer was observed at the cement/bone interface at 24 weeks. Stained sections showed the formation of a fibroconnective capsule around the residual cement, which presumably slows down new bone formation. Nevertheless, quantitative bone remodeling was accelerated in the cement group; mineral apposition as well as adjusted apposition rates were higher, and the formation period as well as the mineralization of osteoid tissue were faster compared with empty cavities and controls. These results point to higher osteoblast activity and better exchange with surrounding tissues in the defects filled with cement.

Topics: Animals; Anthraquinones; Biodegradation, Environmental; Bone Cements; Bone Substitutes; Calcium Phosphates; Disease Models, Animal; Female; Femur; Injections; Materials Testing; Osseointegration; Oxytetracycline; Sheep

Fluorescence microscopy was used for evaluation of new bone formation in 16 canine mandibles augmented with hydroxylapatite (HA) granules. Three fluorochromes were injected at different time intervals during therapeutic radiation treatment. Oxytetracycline, DCAF, and alizarin-complexone were given intravenously to mark the bone level at these times, respectively. Oxytetracycline, which defined the baseline of bone at implantation of HA, was detectable in 42% of animals that were irradiated and in no animal of the nonirradiated control group. The marker DCAF, designating levels of bone at the start of radiation, was demonstrated in 92% of irradiated animals, and in 75% of animals in the control group. The uptake of alizarin-complexone determined the level of bone found at the end of irradiation. This marker was demonstrated in 50% of the dogs irradiated and in 75% of the control dogs. Bony trabeculae were found between and at the surface of the HA granules. New generation of bone directly on the HA granule and in the surrounding haversian systems as part of normal bone turnover was demonstrated to take place more than 5 months after implantation of HA.

Topics: Alveolar Bone Loss; Alveolar Process; Alveolar Ridge Augmentation; Animals; Anthraquinones; Dogs; Durapatite; Fluoresceins; Fluorescent Dyes; Hydroxyapatites; Male; Mandible; Microscopy, Fluorescence; Osteogenesis; Oxytetracycline

The type of fixation (rigid skeletal vs. wire) was assessed against embryologic origin (membranous vs. endochondral) and recipient site (depository vs. resorptive) as variables affecting inlay and onlay bone-graft survival in 20 mature dogs. Wet weight and volume measurements were made at operation and at sacrifice (16 weeks). The results were as follows: (1) Rigid skeletal fixation increased bone-graft volume survival over wire fixation (p less than 0.05). (2) Fixation (i.e., rigid skeletal) and embryologic origin (i.e., membranous) were equal determinants of bone-graft volume survival (p less than 0.001); the recipient site was not significant for onlay bone graft survival. (3) Embryologic origin was the only significant determinant of weight survival (p less than 0.001). (4) Inlay bone grafts demonstrated greater weight and volume survival than onlay bone grafts (p less than 0.05). (5) Histologic and microradiographic studies demonstrated bony union of bone grafts fixed with rigid skeletal fixation, while fibrous union predominated in bone grafts fixed with wire technique.

Topics: Alveolar Ridge Augmentation; Animals; Anthraquinones; Bone and Bones; Bone Plates; Calcification, Physiologic; Dogs; Graft Survival; Microradiography; Microscopy, Fluorescence; Oral Surgical Procedures, Preprosthetic; Organ Size; Oxytetracycline