tetracycline and fluorexon

A method for the mass marking of ide Leuciscus idus larvae by feeding them Artemia salina nauplii that were immersed in different solutions of alizarin red S, tetracycline hydrochloride and calcein was tested. The best quality marks were obtained after feeding fish for 4 days with nauplii that had been immersed in 200 mg l(-1) alizarin red S.

Topics: Animal Feed; Animals; Anthraquinones; Artemia; Cyprinidae; Fluoresceins; Fluorescent Dyes; Larva; Otolithic Membrane; Staining and Labeling; Tetracycline

The purposes of the present study were to evaluate the effects of frequent applications of low-level laser therapy (LLLT) on corticotomy-assisted tooth movement in a beagle dog model and to compare the effects in the mandible and maxilla.. In 4 male beagles, the maxillary and mandibular second premolars were extracted. The third premolars were corticotomized and then protracted from the canines with a continuous force of 200 g. Daily LLLT (using an aluminum gallium indium phosphide [AlGaInP] diode) was applied at the buccal mucosa of the corticotomized premolars on 1 side only. The tooth movement was measured for 8 weeks. Fluorochromes were injected intravenously at the start of the experiment (T0) and after 2 (T2), 4 (T4), and 8 (T8) weeks to evaluate new bone formation on the tension sides. Histomorphometric and immunohistologic evaluations were performed.. In the mandible, the movement of the corticotomized premolars in the LLLT plus corticotomy group was less than that in the corticotomy-only group, although the difference was not statistically significant. In the maxilla, no significant differences between the 2 groups were found. Osteoclastic and proliferating cell activities and the amount of new bone formation were greater in the mandibular LLLT plus corticotomy group than in the corticotomy-only group.. The frequent application of LLLT showed no significant effect on the corticotomized tooth movement.

Topics: Acid Phosphatase; Alveolar Process; Animals; Anthraquinones; Bicuspid; Bone Resorption; Cell Proliferation; Dogs; Fluoresceins; Fluorescent Dyes; Isoenzymes; Lasers, Semiconductor; Low-Level Light Therapy; Male; Mandible; Maxilla; Models, Animal; Orthodontic Wires; Osteoclasts; Osteogenesis; Pilot Projects; Proliferating Cell Nuclear Antigen; Root Resorption; Tartrate-Resistant Acid Phosphatase; Tetracycline; Time Factors; Tooth Movement Techniques

This study evaluated whether growing rats were appropriate animal models of glucocorticoid-induced osteoporosis. The 3-month-old male rats were treated with either vehicle or prednisone acetate at 1.5, 3.0, and 6.0 mg/kg/day by oral gavage, respectively. All rats were injected with tetracycline and calcein before sacrificed for the purpose of double in vivo labeling. Biochemistry, histomorphometry, mechanical test, densitometry, micro-CT, histology, and component analysis were performed. We found that prednisone treatments dose dependently decreased body weight, serum biomarkers, biomechanical markers, bone formation, and bone resorption parameters in both tibial and femoral trabecular bone without trabecular bone loss. We also found that significant bone loss happened in femoral cortical bone in the glucocorticoid-treated rats. The results suggested that prednisone not only inhibited bone formation, but also inhibited bone resorption which resulted in poor bone strength but with no cancellous bone loss in growing rats. These data also suggested that the effects of glucocorticoid on bone metabolism were different between cortical bone and trabecular bone, and different between tibia and femur. Growing rats may be a glucocorticoid-induced osteoporosis animal model when evaluated the effects of drugs upon juvenile patients exposed to GC for a long time.

Topics: Acetates; Animals; Biomarkers; Biomechanical Phenomena; Body Weight; Bone Resorption; Densitometry; Disease Models, Animal; Dose-Response Relationship, Drug; Fluoresceins; Glucocorticoids; Male; Osteoporosis; Prednisone; Principal Component Analysis; Rats; Rats, Sprague-Dawley; Stress, Mechanical; Tetracycline; Time Factors; X-Ray Microtomography

Placement of mini-implants carries with it the risk of iatrogenic damage to the adjacent root surfaces. The aims of this study were to assess the type of trauma incurred on tooth roots after contact or approximation with mini-implants during placement, and to observe and analyze the healing responses via histologic analysis.. Four male minipigs were used as experimental subjects. Twenty mini-implants (1.6 × 8 mm) were implanted in each minipig into the buccal sides of all 4 quadrants between the roots of teeth so that contact or approximation between the mini-implant and root surface occurred, with the aid of dental fluoroscopy. All mini-implants on the left side of the mouth were left in situ, and all mini-implants on the right side were removed immediately after placement. The minipigs were killed at 4-week intervals up to week 16, and histologic sections were made.. When mini-implants were left in situ, the root surface was mostly resorbed away from the mini-implant thread. Partial repair started at 8 weeks. When the mini-implant thread was left touching the root, there was no normal healing response. If the mini-implant was placed less than 1 mm from the periodontal ligament, resorption was evident on the root surface. Abnormal healing responses were seen when the pulp tissue was ruptured, mostly through osteodentin formation. In all instances after mini-implant removal immediately after placement, varying degrees of cementum repair was observed.. Immediate removal of the mini-implant leads to cementum repair, whereas leaving the mini-implant in place will cause either a delay in repair or no repair. Placing mini-implants less than 1 mm from the root surface causes root-surface resorption.

Topics: Animals; Anthraquinones; Cementogenesis; Dental Cementum; Dental Implants; Dental Pulp; Dentin, Secondary; Fluoresceins; Fluorescent Dyes; Fluoroscopy; Male; Orthodontic Anchorage Procedures; Periodontal Ligament; Root Resorption; Specific Pathogen-Free Organisms; Swine; Swine, Miniature; Tetracycline; Time Factors; Tooth Root; Wound Healing

Bone-specific compounds have been used effectively for the detection of bone mineralization, growth, and morphological changes. These agents typically contain iminodiacetic acid groups that can form complexes with apatite and fluoresce in the visible spectrum. We exploited a subset of these chemical chelators to produce a near-infrared (NIR) optical bone marker for preclinical animal imaging. By conjugating target compounds to IRDye 800CW, we extended the effective fluorescence signal detection to the NIR region without affecting the compound's ability to function as a marker of the mineralization process. Calcein and a tetracycline derivative (BoneTag agent [BT]) bound specifically to differentiated mineralized osteoblast cultures, with the latter exhibiting 6-fold higher signal intensities. Subsequent in vivo testing demonstrated effective skeletal labeling with IRDye 800CW BT. We were able to identify a changing mineralization front in bone sections from (i) normal growing mice injected with IRDye 800CW BT 6weeks prior to the administration of IRDye 680 BT and (ii) an osteoporosis mouse model comparing cortical bone in sham-treated and ovariectomized mice. These results provide evidence that the NIR-labeled BT is effective as a general marker of skeletal features and an indicator of the bone mineralization and remodeling processes.

Topics: Animals; Biomarkers; Bone Remodeling; Calcification, Physiologic; Cell Line; Disease Models, Animal; Fluoresceins; Indoles; Mice; Mice, Nude; Microscopy, Fluorescence; Osteoporosis; Spectroscopy, Near-Infrared; Tetracycline; Whole Body Imaging

The objective of this study was to evaluate the short-term effects of clodronate, a first-generation bisphosphonate, on early alveolar bone remodeling and root resorption related to orthodontic tooth movement.. The samples consisted of 54 sex-matched Wistar rats (weight, 180-230 g) allocated to the 2.5 mmol/L clodronate, 10 mmol/L clodronate, and control groups (n = 18 for each group). After application of a nickel-titanium closed-coil spring (force, 60 g) between the maxillary central incisor and first molar, 2.5 mmol/L of clodronate, 10 mmol/L of clodronate, or saline solution was injected into the subperiosteum adjacent to the maxillary first molar every third day. All animals received tetracycline, calcein, and alizarin red by intraperitoneal injection at 1, 6, and 14 days, respectively. The amounts of tooth movement were measured at 3, 6, 9, 12, and 15 days. The animals were killed at 4, 7, and 17 days. Histomorphometric analyses of bone mineral appositional rate, labeled surface, percentage of root resorption area, and number of root resorption lacunae of the mesiobuccal root of the maxillary first molar at 4, 7, and 17 days were done. One-way analysis of variance (ANOVA) with the post-hoc test were done for statistical analyses.. Rats in the 10 mmol/L clodronate group had significant decreases of tooth movement (12 and 15 days, P <0.05) and percentages of root resorption area and numbers of root resorption lacunae (7 day, P <0.05), and increases of labeled surface and mineral appositional rates (17 day, P <0.05) over those of the 2.5 mmol/L clodronate and control groups.. Although clodronate might decrease root resorption related to orthodontic tooth movement, patients should be informed about a possible decrease in the amount of tooth movement and a prolonged period of orthodontic treatment.

Topics: Alveolar Process; Animals; Anthraquinones; Bone Density Conservation Agents; Bone Remodeling; Calcification, Physiologic; Clodronic Acid; Dental Alloys; Female; Fluoresceins; Fluorescent Dyes; Incisor; Male; Molar; Nickel; Orthodontic Wires; Rats; Rats, Wistar; Root Resorption; Stress, Mechanical; Tetracycline; Time Factors; Titanium; Tooth Movement Techniques

Modifying the balance between resorption and apposition through selectively injuring the cortical plate of the alveolus has been an approach to speed tooth movement and is referred to as periodontally accelerated osteogenic orthodontics. The aim of this study was to investigate the alveolar response to corticotomy as a function of time and proximity to the surgical injury in a rat model.. Maxillary buccal and lingual cortical plates were injured in 36 healthy adult rats adjacent to the upper left first molars. Twenty-four animals were euthanized at 3, 7, or 11 weeks. In one group, the maxillae were removed and stripped of soft tissues, and histomorphometric analysis was performed to study alveolar spongiosa and periodontal ligament (PDL) modeling dynamics. Catabolic activity was analyzed with tartrate-resistant acid phosphatase-positive osteoclasts and preosteoclasts. Anabolic actions were measured using a fluorescent vital bone stain series followed by sacrifice at 30 and 51 days. To further analyze the new bone formation, a separate group of animals were fed with calcein fluorescent stain and processed for non-decalcified fluorescent stain histology.. At 3 weeks, the surgery group had significantly (P <0.05) less calcified spongiosa bone surface, greater periodontal ligament surface, higher osteoclast number, and greater lamina dura apposition width. The catabolic activity (osteoclast count) and anabolic activity (apposition rate) were three-fold greater, calcified spongiosa decreased by two-fold, and PDL surface increased by two-fold. Surgical injury to the alveolus that induced a significant increase in tissue turnover by week 3 dissipated to a steady state by postoperative week 11. The impact of the injury was localized to the area immediately adjacent to the decortication injury.. Selective alveolar decortication induced increased turnover of alveolar spongiosa, and the activity was localized; dramatic escalation of demineralization-remineralization dynamics is the likely biologic mechanism underlying rapid tooth movement following selective alveolar decortication.

Topics: Acid Phosphatase; Alveolar Process; Animals; Anthraquinones; Biomarkers; Bone Remodeling; Bone Resorption; Cell Count; Fluoresceins; Fluorescent Dyes; Isoenzymes; Maxilla; Models, Animal; Osteoclasts; Osteogenesis; Osteotomy; Periodontal Ligament; Rats; Tartrate-Resistant Acid Phosphatase; Tetracycline; Time Factors

Titanium is the ideal metal for intra-osseous dental implants. It permits the natural formation of an oxide layer on its surface and thereby it prevents the release of potentially toxic molecules. New formation of bone around implants, partially placed into the bone marrow cavity, is a gradual process that runs from the endosteum to the surface of the implant. Deposition of hydroxyapatite crystals on collagen type I fibrils is initiated by acidic proteins and leads to bone mineralization. This study analyzed the effects of hydroxyapatite upon peri-implant bone formation after insertion of smooth titanium implants. Screw-shaped smooth titanium implants of 3.75 mm thickness and 8.5 mm length were inserted into the metaphysis of rabbit tibia, either together with bovine hydroxyapatite into the right tibia or in controls without hydroxyapatite into the left tibia. Polyfluorochrome tracers (alizarin complex, calcein, tetracycline) were injected subcutaneously at different time intervals after implantation to evaluate the time frame of bone new formation over a period of 8 weeks. All samples were processed for histology and analyzed by fluorescence and polarizing microscopy. Our results showed a higher quantity of mature type I collagen fibers around implants and an acceleration of bone formation in the presence of hydroxyapatite. Mainly immature organic matrix was formed at the surface of implants in controls. The presence of hydroxyapatite seems to promote the maturation of collagen fibers surrounding the titanium implants and to support osteoconduction. Moreover, new formation of bone was faster in all samples where implants were inserted together with hydroxyapatite.

Topics: Animals; Anthraquinones; Bone and Bones; Bone Development; Bone Remodeling; Bone Screws; Coloring Agents; Drug Implants; Durapatite; Female; Fluoresceins; Models, Animal; Rabbits; Tetracycline; Titanium

This study analyzed the effect of the platelet count in platelet-rich plasma (PRP) on bone regeneration in vivo. Twenty male New Zealand white rabbits were used. PRP was produced using the Platelet Concentrate Collection System (PCCS) (3i, Miami, FL, USA). After inducing ketamine-xylazine anaesthesia, a self-tapping titanium screw (Branemark MK III TiUnite, 3.75 x 7 mm) was inserted in each distal femur; the femurs were randomized so that one side was treated with PRP while the other (control) was not. Intravital fluorochrome staining was performed on days 1, 7 (1.5 ml of 2% doxycycline/kg bodyweight), 14 (6% xylenol orange, 1.5 ml/kg), and 21 (1% calcein green, 5 ml/kg). Animals were euthanized on day 28 (n = 20). Specimens were prepared for histomorphological evaluation according to Donath and Breuner [J. Oral Pathol. 11 (1982) 318]. Comparing the bone regeneration (fluorochrome staining) in the 4-week implants (n = 19), the only significant difference (sign test, P = 0.004) was seen with intermediate platelet concentrations (n = 9,503,000-1,729,000 platelets/microl PRP). There were no differences in the bone/implant contact rates between the test and the control side among the three groups. The platelet concentration required for a positive PRP effect on bone regeneration seems to span a very limited range. Advantageous biological effects seem to occur when PRP with a platelet concentration of approximately 1,000,000/microl is used. At lower concentrations, the effect is suboptimal, while higher concentrations might have a paradoxically inhibitory effect. On the other hand, the effect of this type of platelet concentrate was not beneficial to accelerate the osseointegration of enosseous dental implants.

Topics: Animals; Blood Platelets; Bone Regeneration; Bone Transplantation; Femur; Fluoresceins; Implants, Experimental; Male; Plasma; Platelet Count; Rabbits; Random Allocation; Staining and Labeling; Tetracycline; Xylenes

The purpose of this study is to analyze the bone remodeling process after the placement of threaded implants with rough (RBM) and hydroxyapatite coated surfaces (HA) in rabbit tibias using polyfluorochrome sequential labeling. Histomorphometry was performed in order to quantify the amount of each label deposited during the healing period. This work demonstrates the possibility of periodic identification of apatite deposition during bone remodeling around titanium and ceramic implants. It has been concluded that the polyfluorochrome sequential labeling is an important tool for identification of bone remodeling after the insertion of titanium and ceramic implants inside rabbit tibias.

Topics: Animals; Anthraquinones; Bone Remodeling; Dental Implants; Dental Materials; Durapatite; Fluoresceins; Models, Animal; Rabbits; Tetracycline; Tibia

This work was designed to observe the dentine incremental lines of the sika deer (Cervus nippon) fawns and to investigate their periodicity using the chronological labeling method with fluorochromes. The incremental lines were observed in decalcified specimens stained by Bodian's silver technique, and the fluorescence-labeled lines were observed in undecalcified and ground specimens. In the silver stained specimens, there were two types of lines, deeply stained thick lines and faintly stained minute regular incremental lines. The intervals and staining intensities of the deeply stained thick lines were very similar to those of the fluorescence-labeled lines in the ground specimens obtained from the same tooth, and hence, it appeared that the both lines were identical. The number of minute incremental lines between the deeply stained thick lines was the same as that of days between the time when each fluorescent labeling injection was made. Therefore, it seemed that each minute incremental line was formed each day. The possibility of age estimation in days using diurnal dentine increments was discussed.

Topics: Age Determination by Teeth; Aging; Animals; Deer; Dentin; Fluoresceins; Staining and Labeling; Tetracycline; Tooth

The purpose of this study was to investigate the incorporation of fresh frozen irradiated membranous allogeneic bone grafts into critical size calvarial defects in the rabbit. Fifteen rabbits had calvarial defects prepared. Twelve rabbits received allogeneic grafts and three received autogenous bone grafts. The rabbits were sacrificed at 9 and 12 months postoperatively, and the specimens were examined radiologically, histopathologically and with fluorescence microscopy. Neovascularization, bone marrow regeneration and new bone formation was evident throughout the grafts however revitalization of the entire graft was incomplete at 12 months. This study revealed that the FFI membranous grafts were well incorporated into rabbit calvarial defects.

Topics: Animals; Anthraquinones; Bone Diseases; Bone Marrow; Bone Matrix; Bone Regeneration; Bone Remodeling; Bone Transplantation; Cryopreservation; Fluoresceins; Fluorescent Dyes; Microscopy, Fluorescence; Neovascularization, Physiologic; Osteoblasts; Osteoclasts; Osteogenesis; Rabbits; Radiography; Skull; Statistics as Topic; Statistics, Nonparametric; Tetracycline; Time Factors; Transplantation, Autologous; Transplantation, Homologous

Our previous histopathological study showed that the augmentation block, prepared from a calcium phosphate cement (CPC) mixed with H2O at powder to liquid ratio of 5 g/mL, placed on the alveolar bone ridge, was gradually replaced by natural bone. In the present study, fluorescent labeling analysis (FLA) and electron probe microanalysis (EPMA) were performed on the same surgical site of the above histopathological study. Fluorescent labeling agents, that would be incorporated into newly formed mineralized tissues, were injected into dogs intramuscularly twice a week during the 3 week period that ended 1 week before sacrifice. The specimens obtained from the block were subjected to FLA for assessing the extent of new bone formation and to EPMA for measuring the elemental (Ca, P, Mg) distributions. FLA results showed the presence of newly formed bone at 1 month after surgery. EPMA results showed that the elemental distributions in the augmentation site were similar to those of the residual bone area at 6 months after surgery. FLA and EPMA examinations also indicated that the implants were surrounded and fixed by natural bone chronologically. A CPC augmentation block is clearly useful for alveolar ridge augmentation and osteointegrated implant fixation.

Topics: Alveolar Process; Alveolar Ridge Augmentation; Animals; Anthraquinones; Bone Cements; Bone Substitutes; Calcification, Physiologic; Calcium; Calcium Phosphates; Dental Implants; Dogs; Electron Probe Microanalysis; Fluoresceins; Fluorescent Dyes; Magnesium; Mandible; Microscopy, Fluorescence; Osseointegration; Osteogenesis; Phosphorus; Surface Properties; Tetracycline; Time Factors

The purpose of this study was to investigate bone dynamics under a denture base, in relation to the intensity of continuous pressure exerted through it to the denture supporting tissue. Two hundred and fifty male rats of Wistar strain were divided into five groups, four of which wore experimental dentures to load continuous pressure of 0.0, 1.0, 10.0 or 20.0 kPa to the molar region of the hard palate. The fifth group was the non-denture-wearing group. Fluorescent labelled palatal bone tissue was stained with Villanueva bone stain and was prepared for the undecalcified grinding section. In the 0.0 kPa group whose mucosa was covered with denture base, although no bone resorption was observed, bone formation was inhibited up to 4 weeks after the denture insertion. Bone dynamics in the 1.0 kPa group was similar to those in the 0.0 kPa group. In the 10.0 and 20.0 kPa groups, bone resorption was observed until 3 and 2 weeks after the denture insertion, and the amount of bone resorption (AoBR) was 24 +/- 17 and 35 +/- 21 lm, respectively. After bone resorption in these groups, although osteoid formation increased earlier than 0.0 kPa group, mineralization showed a similar time course with 0.0 kPa group. In conclusion, bone dynamics under a denture base caused by continuous pressure exerted through it was revealed to show a time course depending on the intensity of the initial pressure. Amount of bone resorption was also revealed to correspond to the intensity of the initial pressure. Bone formation following bone resorption did not cause equivalent recovery of the bone surface level to the level observed in the case without bone resorption.

Topics: Acrylic Resins; Analysis of Variance; Animals; Bone Matrix; Bone Resorption; Calcification, Physiologic; Dental Alloys; Denture Bases; Denture Design; Fluoresceins; Fluorescent Dyes; Image Processing, Computer-Assisted; Molar; Osteoblasts; Osteoclasts; Osteogenesis; Palate, Hard; Periodontium; Pressure; Rabbits; Rats; Rats, Wistar; Statistics as Topic; Statistics, Nonparametric; Stress, Mechanical; Tetracycline; Time Factors

The effect of calcium supplementation on the bone dynamics in the hard palate of the molar region (maxilla), mandible and proximal tibia in experimental osteoporotic rats was examined. Ninety ovariectomized (OVX) and 45 sham-OVX Wistar female rats were used in this study. All the rats received surgical operation at 6 weeks of age. Ovariectomized rats were fed on a low calcium diet (0.02%) for 12 weeks post-operation, and then randomly divided into the two following groups. One group was fed on high calcium diet (2.30%) (OVX-HCa) and the other group was remained on the low calcium diet (OVX-LCa). Sham-OVX rats were fed on regular calcium diet (1.15%) during the experimental period (Sham-OVX). Histomorphological analysis was carried out from 12 to 32 weeks post-operation. On undecalcified thin section, bone volume, eroded surface, osteoid surface and bone formation rate were calculated for cortical bone of the maxilla, and for cancellous bone of the mandible and proximal tibia. In the OVX-LCa group, compared with the Sham-OVX group, decrease of the bone volume and increase of the bone resorption and formation parameters were detected throughout the observation periods. In the OVX-HCa group, compared with the OVX-LCa group, increase of the bone volume and temporarily increased parameters of bone formation at 1 week after feeding on high calcium diet were observed in the maxilla, but these changes were not observed in the mandible and proximal tibia. Moreover, the bone resorption and formation parameters in the maxilla, mandible and proximal tibia in the OVX-HCa group became equivalent to the Sham-OVX levels with the passage of time.

Topics: Analysis of Variance; Animals; Body Weight; Bone Matrix; Bone Resorption; Calcium, Dietary; Dietary Supplements; Disease Models, Animal; Female; Fluoresceins; Fluorescent Dyes; Image Processing, Computer-Assisted; Mandible; Maxilla; Osteogenesis; Osteoporosis; Ovariectomy; Palate, Hard; Random Allocation; Rats; Rats, Wistar; Statistics as Topic; Tetracycline; Tibia

An association between postmenopausal osteoporosis and tooth loss has been proposed. However, histomorphometrical changes in alveolar bone following estrogen deficiency are rarely reported with data on microtrabecular structural changes. To clarify the relationship between estrogen deficiency and tooth loss, we histomorphometrically analyzed the trabecular structural changes of mandibular alveolar bone in ovariectomized rats. Twenty-four adult female Fischer rats were used. Eight rats were sacrificed on day 0 (baseline). The remaining 16 rats were divided into two groups. One group was ovariectomized bilaterally (OVX) and the other group was subjected to sham surgery (Sham). After administration of tetracycline and calcein, the animals were sacrificed 60 days after surgery. Bone histomorphometry, node-strut analysis and measurement of thickness of alveolar bone proper were performed on the interradicular septum of the first molar on the sagittal surface. The trabecular bone volume and trabecular number of the OVX group were significantly lower than those of the baseline and Sham groups. All of the bone resorptive and formative parameters of the OVX group were significantly higher (about one-and-a-half times) than those of the Sham group. Several osteoclasts were seen lining the irregular, eroded surface facing the bone marrow in the OVX group. Furthermore, the OVX group tended to have low microtrabecular stiffness and showed significantly thinner distal alveolar bone proper than in the baseline and Sham groups. In summary, estrogen deficiency caused osteoporotic changes and thin alveolar bone proper in the interradicular septum of rat first molar. This phenomenon might accelerate destruction of alveolar bone and tooth loss, especially in elderly women affected by periodontal disease.

Topics: Alveolar Process; Analysis of Variance; Animals; Bone Density; Bone Marrow; Bone Remodeling; Bone Resorption; Disease Models, Animal; Estrogens; Female; Fluoresceins; Fluorescent Dyes; Mandible; Microscopy, Confocal; Molar; Osteoclasts; Osteoporosis; Ovariectomy; Ovary; Rats; Rats, Inbred F344; Statistics as Topic; Tetracycline

Fourteen 5-week-old male Sprague-Dawley rats were equally divided into two groups, sham-operated and gastrectomized. Tetracycline and calcein were given to label dentine. Four weeks after surgery, blood was collected for measurement of serum iron, calcium and parathyroid hormone (PTH) and the mandibles and maxillae were then removed. Sagittal sections of the maxilla or cross-sections of the mandible were prepared and examined. Backscattered electron images of the maxilla were taken and the iron content at the neck of incisors was measured by energy-dispersive X-ray. The dentine apposition rate in maxillary incisors was measured by fluorescence microscopy. Serum iron was significantly decreased, while PTH was significantly elevated without any change in the serum calcium in gastrectomized rats. Gastrectomy caused a gross loss of iron content in superficial enamel. The dentine apposition rate was significantly reduced by 30%. Both cortical and cancellous bone in the mandibula were significantly reduced. However, the total bone area in gastrectomized rats was similar to that in sham-operated rats. These results suggest that bone resorption was enhanced and dentine formation was reduced after gastrectomy.

Topics: Anemia, Iron-Deficiency; Animals; Bone Resorption; Calcium; Dental Enamel; Dentin; Dentinogenesis; Electron Probe Microanalysis; Fluoresceins; Fluorescent Dyes; Gastrectomy; Incisor; Iron; Malabsorption Syndromes; Male; Mandible; Maxilla; Microscopy, Electron; Microscopy, Fluorescence; Parathyroid Hormone; Rats; Rats, Sprague-Dawley; Statistics as Topic; Tetracycline

The effects of orchidectomy on bone metabolism in male beagle dogs were examined using twelve 2-year-old dogs that were orchidectomized. The dogs' bilateral iliac bones, double-labeled with tetracycline and calcein for the histomorphometry, were obtained from three dogs prior to orchidectomy and at 3, 6, 9, and 12 months afterwards. The serum biochemical constituents related to bone metabolism were examined before and every month after orchidectomy. Between 1 and 6 months after orchidectomy, the value of serum testosterone decreased (1 month), while the levels of parathyroid hormone, calcitonin, total calcium, osteocalcin, and alkaline phosphatase activity increased significantly, indicating a high bone turnover. The mean trabecular thickness and the fraction of labeled osteoid surface decreased significantly 3 months after orchidectomy, but other histomorphometric parameters were unchanged. In the period 7-12 months after orchidectomy, the parathyroid hormone level increased ever and above that of the first 6-month period, while the levels of calcitonin, osteocalcin, alkaline phosphatase activity, and phosphorus decreased. The bone volume, mean trabecular thickness, and the fraction of labeled trabecular surface decreased significantly compared with the pre-orchidectomy values. These findings indicate an imbalance in bone metabolism (i.e. bone resorption > bone formation). These results indicate that a loss of bone volume accompanied the fall in sex hormone levels following orchidectomy and suggest that the orchidectomized dog is available as an animal model for studying osteoporosis caused by hypogonadism and the decline of sex functions in men.

Topics: Alkaline Phosphatase; Animals; Biopsy; Body Weight; Bone and Bones; Bone Remodeling; Calcitonin; Calcium; Disease Models, Animal; Dogs; Fluoresceins; Fluorescent Dyes; Ilium; Image Processing, Computer-Assisted; Male; Microscopy, Fluorescence; Orchiectomy; Osteocalcin; Parathyroid Hormone; Phosphorus; Protein Synthesis Inhibitors; Testosterone; Tetracycline

The twy (tiptoe-walking-Yoshimura) mouse, established in Japan in 1978 by brother-sister mating of ICR strain mice, is a valuable mutant as a model of ossification of the posterior longitudinal ligament (OPLL). OPLL causes severe myelopathy and has been thought to be very similar to ankylosing spinal hyperostosis (ASH) and diffuse idiopathic skeletal hyperostosis (DISH). In the twy mouse, both an increase in vertebral cortical membranous bone formation and a decrease in trabecular bone mass due to accelerated bone resorption occur simultaneously. This process is attributed to an inherited autosomal recessive single gene (twy). Calcitonin's suppression of bone resorption has been well established in the past, whereas the effects of this hormone on bone formation remain to be defined. Of particular interest is the simultaneous action of calcitonin on the abnormally accelerated bone formation and resorption. Thirty twy mice and 14 ICR mice were divided into seven groups, and changes induced by calcitonin on vertebral cortical appositional rate and on trabecular bone mass were investigated histomorphometrically. Results were (1) osteoclastic activity on trabecular surface was clearly suppressed by chicken calcitonin injected subcutaneously for 4 weeks; (2) no significant difference between the lumbar vertebral periosteal bone formation of calcitonin (CA) and vehicle-administrated twy mice groups. However, on the periosteal surface of the cervical vertebrae of the 6-week-old twy mice, the abnormally accelerated bone formation was suppressed by CA administration. This was also true for the elderly twy mice, although the effect was less pronounced. In conclusion, CA suppressed the abnormally hyperactivated periosteal bone formation. Results also suggested a possible therapeutic value of CA for OPLL.

Topics: Animals; Bone Diseases, Metabolic; Bone Remodeling; Calcitonin; Cervical Vertebrae; Disease Models, Animal; Female; Fluoresceins; Fluorescent Dyes; Hyperostosis, Diffuse Idiopathic Skeletal; Lumbar Vertebrae; Male; Mice; Mice, Inbred ICR; Mice, Mutant Strains; Ossification of Posterior Longitudinal Ligament; Periosteum; Radiography; Tetracycline

Topics: Alloys; Animals; Artifacts; Biocompatible Materials; Bone Resorption; Calcium; Fluoresceins; Materials Testing; Osseointegration; Prostheses and Implants; Rats; Scattering, Radiation; Spectrum Analysis; Tetracycline; Time Factors; Titanium

Changes in cancellous bone of the rat mandibular condyle following estrogen deficiency were histomorphometrically examined with 120-day-old female Fischer rats. Sixty-four animals were either ovariectomized bilaterally (ovx) or subjected to sham surgery (sham), and eight from each group were killed at 7, 14, 30, and 60 days after surgery. Seven intact animals were killed on day 0. Before killing, tetracycline and calcein were administered to all animals. Following histological observation, bone histomorphometry of the mandibular condyle was done using a confocal laser scanning microscope and an image analyzer. The sampling site was divided into two regions for analysis: (1) a "subchondral region," formed by the region connected to cartilage; and (2) a "central region," formed by the region beneath the former. The changes in these two regions were analyzed separately. In the sham group's condyle, the bone volume of the subchondral and central regions increased with the passage of time, although the bone turnover became low. This bone gain could be due to the effects of growth and the mechanical stimulus by occlusal load. In the subchondral region of the ovx group's condyle, the bone volume decreased significantly at 7 days, but recovered to reach approximately the same value as the sham group from 14 days onward. In the central region of the ovx group's condyle, the bone volume was unchanged, but revealed a significantly lower value than that of the sham group at 60 days (p < 0.01). Thus, ovariectomy inhibited bone gain, which was observed in the sham group's condyle even though there was no bone loss. On the other hand, the trabecular separation in the ovx's condyle of both the subchondral and central regions increased considerably and small marrow cavities interconnected to form a large bone marrow. Therefore, the ovx rat mandibular condyles dynamically altered their structures under the effects of estrogen deficiency and occlusal loads. Consequently, estrogen deficiency induced transient subchondral bone loss and recovery, whereas, in the central region, it inhibited bone gain. This suggests that mechanical loading modulates the normal ovx-induced bone loss found in other parts of the skeleton.

Topics: Animals; Bone Density; Bone Marrow; Cell Count; Estrogens; Female; Fluoresceins; Humans; Mandibular Condyle; Microscopy, Confocal; Osteoclasts; Osteoporosis, Postmenopausal; Ovariectomy; Radiography; Rats; Rats, Inbred F344; Tetracycline

The effects of a combination of mild exercise and GH injections on bone were studied in old female rats. Biosynthetic human GH, 2.7 mg/kg/day, was injected s.c. for 73 days. Exercised rats ran 8 m/min on a treadmill for 1 h/day. All rats (age 21 months old) were labeled with a tetracycline injection 56 days and a calcein injection 11 days before killing. The GH injections resulted in an 11-fold increase in femoral middiaphyseal bone formation rate and a 12% increase in cross-sectional area compared with the saline-injected group. The mild exercise doubled the mineralizing surface but did not influence the bone formation rate significantly. The combination of GH injections plus exercise, however, resulted in a further increase of 39% in bone formation rate, primarily at the anterolateral aspects, and an increase of 5% in cross-sectional area compared with the group injected with GH only. The femur ultimate breaking load was increased by 37% and the stiffness by 42% in the group injected with GH compared with the saline-injected group. Exercise alone did not influence the femur mechanical properties. The combination of GH injections plus exercise induced a 4% further increase in ultimate breaking load and 7% further increase in stiffness compared with the group injected with GH alone. The GH injections induced a 117% increase in serum insulin-like growth factor I. The GH-insulin-like growth factor I axis stimulates recruitment of osteoblast precursor cells, resulting in increased bone formation at the periosteal surface. GH injections and mild excercise in combination modulate and increase further the formation and strength of cortical bone in old female rats.

Topics: Aging; Animals; Biomechanical Phenomena; Bone Remodeling; Female; Femur; Fluoresceins; Fluorescent Dyes; Human Growth Hormone; Humans; Insulin-Like Growth Factor I; Physical Exertion; Rats; Rats, Wistar; Tensile Strength; Tetracycline

Differences in trabecular and cortical bone loss have been demonstrated clinically, but differences in bone loss at different skeletal sites remain unclear. We examined regional variations in bone loss histomorphometrically in two strains of mice in which osteopenia progresses spontaneously: tiptoe-walking Yoshimura (twy) mice (from 4 to 37 weeks of age) and senescent ICR mice (from 4 to 88 weeks of age). Morphometrical measurements were obtained to investigate the changes with age in trabecular bone area and anterior cortical bone width in the lumbar vertebral body, trabecular bone area in the tibia, bone area in the parietal bone, and the cortical index in the humerus. Results showed that, in twy mice, trabecular turnover was higher than in ICR mice, and bone loss progressed in the following order: tibial trabecular bone, lumbar trabecular bone, parietal bone, lumbar anterior cortical bone, and the humerus. In ICR mice, bone formation declined after 60 weeks. Bone loss progressed in tibial trabecular bone and the parietal bone at 60 weeks of age, followed by lumbar trabecular bone, lumbar anterior cortical bone, and the humerus at 88 weeks of age. Bone loss varied at each site and between the two mouse strains, with different bone turnover rates. The findings of the present study indicate that special attention should be paid to regional variations in the progression of bone loss associated with differences in pathologic features.

Topics: Aging; Animals; Body Weight; Bone Development; Bone Diseases, Metabolic; Disease Progression; Female; Fluoresceins; Humerus; Mice; Mice, Inbred ICR; Mice, Mutant Strains; Osteoporosis; Parietal Bone; Spine; Tetracycline; Tibia

In the compact bony otic capsule remodeling is low, and bone remodeling units are distributed centrifugally in relation to inner ear tissues and spaces. Fluorochrome-labeled bone remodeling units are scarce, abortive, and tortuous with no uniform direction of movement. This study presents a method for the estimation of volume-referent bone turnover based on measurements of the fractional area between labels after sequential labeling with osteofluorochromes. The applicability of this method is tested against a classical quantification method in undecalcified cortical specimens from the canine humerus, where both methods can be used. The estimate of bone turnover derived from the new sequential labeling in eight dogs is 7.4% (SEM 2.1%) per year and the classic estimate derived from calculations of the formative osteonal area and the formative period yields 6.9% (SEM 2.1%) per year. Agreement is sufficient to justify future measurements of absolute bone turnover in sequentially labeled perilabyrinthine bone.

Topics: Animals; Bone Density; Bone Remodeling; Bone Resorption; Dogs; Fluoresceins; Fluorescent Dyes; Forelimb; Humerus; Male; Microscopy, Fluorescence; Models, Biological; Tetracycline

The present study was designed to compare the amount and regional distribution of bone formation around hydroxyapatite (HA) implants in normal (control) rats with that of animals with diabetes mellitus (DM), induced by streptozotocin 2 weeks prior to implant placement. Calcein (CAL), alizarin complexone (AL), and tetracycline (TC) were injected on the 7th, 14th, and 21st days after implantation, respectively, and the rats were sacrificed on the 28th day after implantation. Seventy-microns undecalcified sections of the HA-bone interface in both groups were then prepared for confocal laser scanning microscopy (CLSM) observation. In both groups, bone formation developed from the HA surface to the endosteum, periosteum, or bone marrow. In the control group, around the HA close to the endosteum and periosteum, the new bone showed an extensive lamination pattern of three color layers (CAL, AL, and TC), but in the DM group the labeling density of TC on the 21st day was low. In contrast, on the lateral part of the HA surface (away from the endosteum and periosteum), there was considerably less bone formation in the control group, and in the DM group it was almost completely suppressed. These findings indicate that bone formation around the HA was initiated from the HA surface in the control group, while in the DM group, bone formation along the lateral part of the HA away from the endosteum and periosteum was almost completely suppressed. Furthermore, it is also suggested that in the new bone along the HA close to the endosteum and periosteum, only calcification on the 21st day was depressed.

Topics: Animals; Anthraquinones; Biocompatible Materials; Bone and Bones; Bone Marrow; Calcification, Physiologic; Diabetes Mellitus, Experimental; Durapatite; Fluoresceins; Fluorescent Dyes; Follow-Up Studies; Implants, Experimental; Indicators and Reagents; Male; Microscopy, Confocal; Osseointegration; Osteogenesis; Periosteum; Rats; Rats, Wistar; Streptozocin; Surface Properties; Tetracycline; Tibia

In the developing tooth, the bisphosphonate HEBP causes hypoplasias and hypomineralization of the enamel and dentine as well as inhibition of acellular cementum formation. Here, we describe a novel effect, associated with dentine mineralization. HEBP was administrated to young rats, and the maxillary molars were analyzed histologically. Localized dentinal nodules, protruding towards the pulp, were found in the developing crown of the molars. They occurred in regions, where the mantle dentine was about to mineralize at the time of the injection, and were more frequent at the mesial cusp side. The nodules accumulated mineral, as evidenced by the fluorescence after calcein and tetracyclin labelling. Histologically, the nodules were separated from the enamel by a layer of mantle dentine and were progressively surrounded by predentine and dentine. The nodules were interpreted to contain transport or metabolism intermediates, which were locally accumulated due to the interruption of the mineralization process by HEBP.

Topics: Animals; Dental Cementum; Dental Enamel; Dental Enamel Hypoplasia; Dentin; Dentinogenesis; Etidronic Acid; Fluoresceins; Indicators and Reagents; Injections, Subcutaneous; Microscopy, Electron, Scanning; Minerals; Molar; Rats; Rats, Sprague-Dawley; Tetracycline; Tooth Calcification; Tooth Diseases

This study was undertaken to determine if autogenous bone can be cultivated in vivo in a porous hydroxylapatite (HA) matrix by ingrowth from underlying bone and if this autogenous HA-bone composite graft can then be transplanted.. Five Göttingen minipigs received subperiosteal implantation of one HA block each (40 x 10 x 10 mm), covered by a polylactic membrane, on the ascending ramus of the mandible. After 5 months, half of each implant was harvested and transplanted as an onlay graft to the horizontal ramus of the mandible with simultaneous insertion of a titanium implant. Polychrome fluorescence labeling was done 1, 2, 4, and 8 weeks postoperatively. After 3 months, the vascular system of the animals was filled with BaSO4 for microangiographic examination, and all blocks were retrieved.. Fluorescence microscopy showed that there was a significant decrease in deposition of the label in the grafted blocks at 1 week when compared with later labels. After the second week, there were no significant changes. A 20% to 30% decrease in the frequency of fluorochrome staining was noted in the upper third of each block. In this region, microangiography demonstrated highly vascularized tissue and limited bone resorption.. It was concluded that cultivation of mandibular bone in a porous matrix under guided bone regeneration is possible and that this autogenous HA-bone composite graft can be transplanted at a later date.

Topics: Angiography; Animals; Anthraquinones; Bone Regeneration; Bone Resorption; Bone Transplantation; Dental Implants; Durapatite; Female; Fluoresceins; Fluorescent Dyes; Haversian System; Lactates; Lactic Acid; Mandible; Microradiography; Microscopy, Fluorescence; Osteoblasts; Polyesters; Polymers; Prostheses and Implants; Swine; Swine, Miniature; Tetracycline; Titanium; Transplantation, Autologous

Distribution of bone remodeling units (BRU) in relation to the perilymphatic space was studied in undecalcified temporal bones from adult rabbits labeled in vivo with bone-seeking fluorochromes. Based on recordings of focal bone formation, relative densities of BRUs inside concentric tissue zones around the inner ear spaces were estimated. Zonal densities of BRUs were found to decline towards the perilymphatic space, lending further support to the existence of a local inner ear mechanism in control of capsular bone tissue dynamics. The possible nature of this mechanism is considered briefly with special reference to inner ear electromechanic activity.

Topics: Animals; Anthraquinones; Bone Density; Bone Remodeling; Demeclocycline; Ear, Inner; Fluoresceins; Haversian System; Microscopy, Fluorescence; Oxytetracycline; Phenols; Rabbits; Sulfoxides; Temporal Bone; Tetracycline; Xylenes

Substances that bind calcium are given to determine where and how fast bone is forming. Several vital dyes are used (tetracycline, calcein, alizarin, xylenol), but it is not known whether the histomorphometric results they provide are equivalent. This work tests whether different fluorochrome labels give the same results when they are quantitatively measured. Twelve-week-old rats (n = 58) were divided into six groups and given double labels IP of calcein, tetracycline HCl, alizarin complexone, or xylenol using a 1-7-1 scheme. Two other groups received either calcein followed by tetracycline, or tetracycline followed by calcein. Our results show that (a) tetracycline hydrochloride leads to a significant underestimation of mineralizing surface when given as the second label, probably because of its weak fluorescence; (b) there were no differences among any of the non-tetracycline labels for any of the histomorphometric measurements; (c) there was no evidence of osteoblast suppression with any label; and (d) there was no evidence that tetracycline caused increased osteoblast resting periods.

Topics: Animals; Anthraquinones; Bone and Bones; Bone Development; Fluoresceins; Fluorescent Dyes; Histocytochemistry; Rats; Rats, Sprague-Dawley; Tetracycline; Xylenes

The effects of long-term prostaglandin E2 (PGE2) on cancellous bone in proximal tibial metaphysis were studied in 7-month-old male Sprague-Dawley rats given daily subcutaneous injections of 0, 1, 3, and 6 mg PGE2/kg/day and sacrificed after 60, 120, and 180 days. Histomorphometric analyses were performed on double fluorescent-labeled undecalcified bone specimens. After 60 days of treatment, PGE2 produced diffusely labeled trabecular bone area, increased trabecular bone area, eroded and labeled trabecular perimeter, mineral apposition rate, and bone formation rate at all dose levels when compared with age-matched controls. In rats given PGE2 for longer time periods (120 and 180 days), trabecular bone area, diffusely labeled trabecular bone area, labeled perimeter, mineral apposition, and bone formation rates were sustained at the elevated levels achieved earlier at 60-day treatment. The eroded perimeter continued to increase until 120 days, then plateau. The observation that continuous systemic PGE2 administration to adult male rats elevated metaphyseal cancellous bone mass to 3.5-fold of the control level within 60 days and maintained it for another 120 days indicates that the powerful skeletal anabolic effects of PGE2 can be sustained with continuous administration.

Topics: Animals; Bone Density; Bone Remodeling; Dinoprostone; Fluoresceins; Male; Microscopy, Fluorescence; Rats; Rats, Inbred Strains; Tetracycline; Tibia

The assessment of new attachment after periodontal treatment has been the focus of continuous research. An approach to longitudinally examine the deposition of cementum was devised by using fluorescence microscopy (FL), contact microradiography (CMR), and toluidine blue staining (TBS) after the injection of three labeling agents known to be incorporated within newly mineralized tissues with different tones: tetracycline, calcein, and alizarin complexion. Three adult Japanese monkeys (male, 6.0 to 8.3 Kg weight) were used for this experiment. Bone defects were surgically created in 24 mandibular sites and a copper plate was inserted for a period of 4 weeks to promote microbial colonization to form periodontal pockets. Scaling and root planing (baseline) were then performed, and the fluorescent agents were administered twice weekly leaving a 1 week interval between the different agents. The mandibular specimens were fixed in neutralized formalin and embedded in polyester resin. Undecalcified sections were prepared 3, 6, and 9 weeks after baseline. Cementum regeneration was confirmed in 18 out of 24 sites; in 6 samples only epithelial proliferation was observed. Regeneration could be seen as early as 2 weeks after debridement. Cementum was identified by observation under FL of a labeled structure, discrimination in the degree of mineralization of dentin by CMR, and by the presence of functional collagen fibers and location of the epithelial border by TBS. In this study the use of three different labeling agents using the three observation techniques was shown to be effective for the longitudinal assessment of cementum regeneration.

Topics: Alveolar Bone Loss; Animals; Anthraquinones; Dental Cementum; Dental Scaling; Fluoresceins; Fluorescent Dyes; Indicators and Reagents; Longitudinal Studies; Macaca; Male; Microradiography; Periodontal Diseases; Periodontal Pocket; Regeneration; Tetracycline; Tolonium Chloride; Tooth Root

The maintenance of alveolar bone is a major clinical objective in dentistry. This is particularly difficult following such local inflammatory episodes as those of periodontitis or the loss of dentition (residual ridge resorption). We present evidence from beagle dogs that local infusion of prostaglandin E1 (PGE) for 3 weeks at doses of 500 to 2000 micrograms per week produces a dramatic, localized formation of alveolar bone in the mandible which exhibits a normal lamellar architecture and mineralization pattern when evaluated by fluorescence microscopy and microradiography. Whether this newly formed bone becomes functionally integrated into the skeleton and can replace bone lost from surgical resections or trauma remains to be established. Nevertheless, these data indicate that predictable local osteogenesis may eventually be produced by infusions of PGE.

Topics: Alprostadil; Alveolar Process; Animals; Dogs; Fluoresceins; Infusion Pumps; Mandible; Microradiography; Microscopy, Fluorescence; Microscopy, Polarization; Osteogenesis; Tetracycline

The purpose of this study was to carry out the histomorphometric assay on the mandibular condylar tissue of the growing rats. Male rats of the Wistar strain at the age of 3, 4, 6, 8 and 10 weeks were used. All rats were injected intravenously with tetracycline and calcein, respectively. They were killed 12 hours after calcein injection. Before embedding in acrylic resin, 3 reference points were marked directly on each condyle to establish the reference plane for the histomorphometry on the ground section. After preparing the ground section, the growth rate of the condyle was obtained by measuring the distance of the two different fluorescent labeling lines. Furthermore, the age-related changes of the relative distribution of the bone, calcified cartilage and prebone (uncalcified bone matrix) were measured under a light microscope by using a grid on the eyepiece reticle. The number of osteoblasts and osteoclasts were also calculated in the same specimen. The following results were obtained: The thickness of the cartilaginous layer and the growth rate of the endochondral bone formation decreased with age. The relative ratio of the bone area in the subchondral tissue increased constantly with age.

Topics: Aging; Animals; Body Weight; Bone Development; Cartilage; Fluoresceins; Male; Mandibular Condyle; Osteogenesis; Rats; Rats, Inbred Strains; Tetracycline

Dentin appositional rates were determined in pregnant and lactating rats and compared with those in non-pregnant, age-matched controls. Appositional rates were calculated from measurements of distance between fluorescent mineralized tissue markers. There were significant increases in dentin apposition during pregnancy, with the greatest increases seen in the first two weeks. Dentin appositional rates decreased significantly during mid-lactation. These results indicate that homeostatic changes during pregnancy and lactation affect mineralized tissue accretion.

Topics: Animals; Dentin; Dentinogenesis; Female; Fluoresceins; Hormones; Incisor; Lactation; Pregnancy; Rats; Rats, Inbred Strains; Tetracycline

Topics: Animals; Bone Development; Fluoresceins; Horses; Methods; Tarsal Bones; Tetracycline