RESUMO
BACKGROUND: It is well-known that oral surgical procedures pose a high risk for medication-related osteonecrosis of the jaw in patients taking bisphosphonates. Although some position papers and guidelines have been published with regard to its treatment, few studies have investigated prevention methods. This study investigates the effectiveness of methenolone enanthate, an anabolic steroid, for the prevention of medication-related osteonecrosis of the jaw. METHODS: Thirty-six Wistar rats were divided into three groups. Two experimental groups, Z and ZM, took zoledronic acid for 6 weeks prior to extraction of the left maxillary first molar. The Group ZM also was given methenolone enanthate continuously for 1 week before and 4 weeks after the extraction. The control group was not given any medication. The rats were euthanized 5 weeks after extraction. The extraction socket was evaluated clinically for bone exposure and histologically for inflammation, hyperemia, collagen fibers, epithelialization, number of osteoclasts, and empty lacunae. RESULTS: Six rats died during the experimental research. The bone exposure rate, mean numbers of attached osteoclasts (in 40× magnification), and empty lacunae (in 100× magnification) were 0%, 4%, and 0.8% in Group C; 75%, 1%, and 8% in Group Z; and 10%, 2.1%, and 3% in Group ZM, respectively. Significant differences exist between all groups regarding the number of empty lacunae. There were significant differences between Group C/ZM and Group Z in terms of bone exposure rate, inflammation, hyperemia, collagen fiber organization, and epithelialization. CONCLUSION: In our tested preclinical model, methenolone enanthate has shown potential for preventing medication-related osteonecrosis of the jaw.
Assuntos
Osteonecrose da Arcada Osseodentária Associada a Difosfonatos , Ratos Wistar , Animais , Ratos , Osteonecrose da Arcada Osseodentária Associada a Difosfonatos/prevenção & controle , Osteonecrose da Arcada Osseodentária Associada a Difosfonatos/etiologia , Masculino , Ácido Zoledrônico/uso terapêutico , Extração Dentária , Distribuição Aleatória , Osteoclastos/efeitos dos fármacos , Imidazóis/farmacologia , Anabolizantes/uso terapêutico , Dente Molar , Difosfonatos/farmacologia , Conservadores da Densidade Óssea/uso terapêutico , Conservadores da Densidade Óssea/farmacologia , Alvéolo Dental/efeitos dos fármacosRESUMO
Background/aim: This study aims to determine the possible embryotoxic effects of propofol on the cerebellum and spinal cord using fertile chicken eggs. Materials and methods: A total of 430 fertile eggs were divided into 5 groups: control, saline, 2.5 mg.kg-1, 12.5 mg.kg-1, and 37.5 mg.kg-1 propofol. Injections were made immediately before incubation via the air chamber. On the 15th, 18th, and 21st day of incubation, 6 embryos from each group were evaluated. Serial paraffin sections taken from the cerebellum and spinal cord were stained with hematoxylin-eosin, Kluver-Barrera, toluidine blue, and periodic acid-Schiff's reaction. The outer granular layer and total cortex thickness were measured, and the linear density of the Purkinje cells was determined. The ratios of the substantia grisea surface area to the total surface area of the spinal cord were calculated. The transverse and longitudinal diameters of the canalis centralis were also assessed. Results: No structural malformation was observed in any embryos examined macroscopically. No significant difference was observed between the groups in terms of development and histologic organization of the cerebellum and spinal cord. However, on the 15th, 18th, and 21st day, the outer granular layer (p < 0.001 for all days) and the total cortex thickness (p < 0.01, p < 0.001, and p < 0.001, respectively) decreased significantly in different propofol dose groups in varying degrees in the cerebellum. Similarly, in the spinal cord, there were significant changes in the ratios of the substantia grisea surface area to the total surface area (p < 0.01 and p < 0.001, respectively). Conclusion: It was concluded that the in-ovo-administered propofol given immediately before incubation has adverse effects on the developing cerebellum and spinal cord. Therefore, it is important for anesthesiologists always to remain vigilant when treating female patients of childbearing age.
Assuntos
Cerebelo , Propofol , Medula Espinal , Animais , Propofol/toxicidade , Propofol/administração & dosagem , Cerebelo/efeitos dos fármacos , Cerebelo/patologia , Cerebelo/embriologia , Medula Espinal/efeitos dos fármacos , Medula Espinal/patologia , Medula Espinal/embriologia , Embrião de Galinha/efeitos dos fármacos , Anestésicos Intravenosos/toxicidade , Anestésicos Intravenosos/administração & dosagemRESUMO
OBJECTIVE: The aim of this study is to determine the possible embryotoxic effects of propofol, a general anaesthetic agent that is commonly used in clinical practice, on peripheral blood lymphocytes using enzyme histochemical techniques. METHODS: For this purpose, 430 laying hen fertile eggs were used for this study. The eggs were divided into 5 groups as control, solvent-control (saline), 2.5 mg kg-1 propofol, 12.5 mg kg-1 propofol, and 37.5 mg kg-1 propofol, and injections were performed via the air sac just before the incubation. The peripheral blood alpha naphthyl acetate esterase and acid phosphatase-positive lymphocyte ratios were determined on the hatching day. RESULTS: No statistically significant difference was found between both alpha naphthyl acetate esterase and acid phosphatase-positive lymphocyte ratios of the control and solvent-control groups. However, when compared with the control and solvent-control groups, statistically significant decreases were observed in the peripheral blood alpha naphthyl acetate esterase and acid phosphatase-positive lymphocyte ratios of the chicks from the propofol-injected groups. Besides, the difference between 2.5 mg kg-1 and 12.5 mg kg-1 propofol groups is not significant, whereas the difference between these 2 groups and the 37.5 mg kg-1 propofol group was statistically significant (P < .05). CONCLUSIONS: It was concluded that propofol given to fertilised chicken eggs just before incubation caused significant decreases in both the peripheral blood alpha naphthyl acetate esterase and acid phosphatase-positive lymphocyte ratios.
RESUMO
This study was aimed to determine the effects of the glucomannan added to aflatoxin- (AF-) contaminated diet on the sacculus rotundus and peripheral blood lymphocytes of New Zealand rabbits by histological and enzyme histochemical methods. Twenty-four adult rabbits of both sexes were divided into four equal groups, namely, as control, glucomannan 0.2 g/day, AF 125 µg/kg/day, and glucomannan combined with AF. The animals in all groups were treated for 12 weeks by the above-mentioned diet. When compared to control, AF-treatment caused significant decrease in alpha-naphthyl acetate esterase- (ANAE-) positive peripheral blood lymphocyte (PBL) percentages. The addition of the glucomannan to AFcontaining diet recovered the adverse effects of AF on sacculus rotundus and increased the ANAE-positive PBL counts. These results suggested that glucomannan was effective against the negative effects of AF in rabbits.
Assuntos
Aflatoxinas/sangue , Aflatoxinas/toxicidade , Linfócitos/citologia , Mananas/farmacologia , Ração Animal , Animais , Aspergillus/metabolismo , Esterases/biossíntese , Feminino , Trato Gastrointestinal/efeitos dos fármacos , Imuno-Histoquímica/métodos , Linfócitos/efeitos dos fármacos , Masculino , Mananas/química , Modelos Estatísticos , Naftóis/química , Coelhos , Projetos de PesquisaRESUMO
OBJECTIVE: The study aimed to evaluate the effects of a mixture of encapsulated essential oils (EOs) addition on nutrient digestion, serum biochemical parameters, peripheral blood alpha-naphthyl acetate esterase (ANAE), and acid phosphatase (ACP-ase) positive lymphocyte ratios and intestinal morphology in laying hens. METHODS: A total of 320 laying hens of 48-wk-old were randomly allotted into 4 treatment groups with 10 replicates of 8 birds in each replicate. The birds were fed a basal diet (control) or the diet added with mixture of EOs (which consist of eugenol, nerolidol, piperine, thymol, linalool, and geraniol) at 50, 100, and 200 mg/kg for period of 84 days. RESULTS: The addition of EOs at 100 or 200 mg/kg increased the dry matter, organic matter, and crude protein digestion as compared to control. The addition of all doses of EOs did not affect serum gamma glutamyl transferase, alanine aminotransferase, and P but increased serum asparate aminotransferase (AST) concentration. The addition of 200 mg/kg EOs increased serum creatinine, while 100 mg/kg decreased Ca concentration. The addition of 100 and 200 mg/kg EOs generally improved ANAE and ACP-ase positive peripheral blood lymphocyte ratios and intestinal morphology. CONCLUSION: It can be concluded that, the addition of 100 or 200 mg/kg encapsulated EOs generally increased apparent nutrient digestion and serum AST concentration, improved ANAE and ACP-ase positive peripheral blood lymphocytes and intestinal morphology in laying hens.
RESUMO
The aim of this study was to determine diameters of blood cells, differential counts of peripheral blood leukocytes, alpha-naphthyl acetate esterase (ANAE), acid phosphatase (ACP-ase) activity of some leukocyte types, and enzymatic positivity percentages of peripheral blood lymphocytes in two hedgehogs species, Hemiechinus auritus, the long-eared hedgehog, and Erinaceus concolor, the southern white-breasted hedgehog. Air-dried peripheral blood smears were stained with May-Grünwald-Giemsa stain. ANAE and ACP-ase were stained in glutaraldehyde-acetone-fixed smears. ANAE-positive lymphocytes displayed a dot-like positivity pattern characterized with 1-5 reddish brown cytoplasmic granules, whereas ACP-ase positive lymphocytes displayed a dot-like positivity pattern characterized with 1-3 pinkish cytoplasmic granules. Monocytes gave a diffuse and strong reaction while neutrophils displayed a weak positive reaction for ANAE and ACP-ase. No difference was observed in mean diameters of peripheral blood cells of these species. It was found that lymphocytes made up the majority (64.3% and 65.5%) of leukocytes, followed by neutrophils (23.9% and 23.3%), eosinophils (9.0% and 7.6%), monocytes (1.8% and 2.3%), and basophils (1.0% and 1.3%) in H. auritus and E. concolor, respectively. Mean ANAE positivity oflymphocytes was 36.6% and 51.3% and ACP-ase positivity was 32.1% and 37.5% for H. auritus and E. concolor, respectively. The ANAE positivity of lymphocytes in E. concolor was significantly (P < 0.05) higher than that of H. auritus.
Assuntos
Ouriços/sangue , Contagem de Leucócitos/veterinária , Animais , Plaquetas/citologia , Eritrócitos/citologia , Leucócitos/citologia , Naftol AS D Esterase/sangue , TurquiaRESUMO
OBJECTIVES: The aim of this study was to determine of the effects of in ovo administered BPA on embryonic development of the tibial growth plate using histological methods in chickens. METHODS: Three hundred and ten fertile eggs of Isa Brown laying parent stock were divided into five groups as untreated control, vehicle-injected control, 50, 100, and 250 µg/egg BPA. At the 13th, 18th, and 21st days of incubation, eggs were randomly opened from each group until 10 live embryos were obtained. Embryos were weighed and crown-rump length was measured. Tibial tissue samples were taken from embryos. Tibia weight, relative tibia weight and tibia length were determined. Tissue samples were fixed in 10% buffered formalin solution. Sections were stained with Safranin O staining methods and zones in the growth plate were measured. Also, proliferating cell nuclear antigen (PCNA) was stained immunohistochemically. RESULTS: The mortality in the BPA treated groups was higher than untreated control group. The results have revealed that mean relative embryo weights, crown-rump length, mean tibia weight, relative tibia weight, and tibia length of BPA treated groups were significantly lower when compared to the untreated control and vehicle-injected control groups. Also, proliferative zone get significantly narrowed, whereas the transitional and hypertrophic zone thickened and PCNA positive chondrocytes increased in growth plate of BPA treated groups. CONCLUSION: These results have suggested that developmental exposure to BPA adversely affected development of the tibial growth plate.
Assuntos
Galinhas , Lâmina de Crescimento , Animais , Compostos Benzidrílicos/toxicidade , Fenóis , TíbiaRESUMO
The effects of bisphenol A on the some plasma cytokine levels and distribution of CD8+ and CD4+ T lymphocytes in spleen, ilealPeyer's patch and bronchus-associated lymphoid tissue in rats were investigated. A total of fourty male Wistar Albino rats were divided into five groups including 8 rats in each one: control, vehicle, BPA 5, BPA 50 and BPA 500 groups. Doses of 5, 50 and 500 µg/kg BPA were dissolved in ethanol, then mixed with corn oil. The control group received no treatment. The vehicle group was given the ethanol-corn oil mixture. BPA 5, BPA 50 and BPA 500 groups were given, respectively, 5, 50, and 500 µg/kg/day orally. In blood samples, IL-4, IL-6, IL-10 and TNF-α plasma levels were determined with ELISA. Tissue samples (spleen, ileal Peyer's patches and lung) were processed by means of routine histological techniques. CD4 and CD8 were stained immunohistochemically. Data obtained from this study showed that, BPA causes the alteration on immune parameters including cytokine profile, distribution of CD8+ and CD4+ T lymhpocytes in spleen and ileal Peyer's patches. Present study indicated that BPA may affect immune systems even at lower doses.Disruption of immun system cells and cytokine levels can result in harmful outcomes triggering autoimmune diseases and immunodeficiencies.
Assuntos
Compostos Benzidrílicos/farmacologia , Brônquios/química , Linfócitos T CD4-Positivos/efeitos dos fármacos , Linfócitos T CD8-Positivos/efeitos dos fármacos , Íleo/química , Nódulos Linfáticos Agregados/efeitos dos fármacos , Fenóis/farmacologia , Baço/química , Administração Oral , Animais , Brônquios/imunologia , Ensaio de Imunoadsorção Enzimática , Íleo/imunologia , Interleucina-4/sangue , Masculino , Ratos , Ratos Endogâmicos WF , Padrões de Referência , Baço/imunologia , Fator de Necrose Tumoral alfa/sangueRESUMO
This study was carried out to describe morphologically and morphometrically the hypoglossal dorsal root and its ganglia, using heads of 20 adult Holstein cattle of both sexes. The dorsal root of the hypoglossal nerve (XII) has always an evident dorsal root ganglion (DRG) including the accessory in 30% (6 of heads) or satellite ganglia in 10% (2 of heads). There were statistically significant differences between the lengths (right: 8.64+/-0.22 mm, left: 7.91+/-0.31 mm, p<0.01) of peripheral roots of the DRG in male. Statistical significance existed in the lengths (right: 7.01+/-0.43, left: 8.27+/-0.47, p<0.05) of the central roots of the DRG in male. Since the histological findings showed that each ganglion placed on the dorsal root of the XII had the general feature of a spinal ganglion, it can be said that the XII has the intracranial peripheral (sensory) fibers and carry directly sensory input to the brain stem. In conclusion, the present study is the first to reveal the morphology of the hypoglossal dorsal root with ganglia in Holstein cattle.
Assuntos
Bovinos/anatomia & histologia , Bovinos/classificação , Gânglios Espinais/anatomia & histologia , Nervo Hipoglosso/anatomia & histologia , Animais , Feminino , MasculinoRESUMO
The aim of the present study was to investigate immunohistochemical distribution of heat shock protein 70 (Hsp70) and proliferating cell nuclear antigen (PCNA) in the mouse placenta at different gestational stages. For this purpose a total of 18 Swiss albino female mice at 12-14 weeks of age were used. Females were sacrificed on days 3 (early), 10 (mid-), and 17 (late) of pregnancy and the implantation sites of the pregnant uterus were sampled. The sections were made transversely through the central region of the implantation site and stained with hematoxylin and eosin for histological examination. PCNA and Hsp70 was stained immunohistochemically. Since the definitive placenta was not still formed on day 3 of pregnancy, Hsp70 and PCNA positivity were evaluated in only luminal epithelium and decidual-stromal cells. On days 10 and 17 of pregnancy, Hsp70 and PCNA positivity were evaluated in labyrinth zone, junctional zone and decidual layer of placenta. Hsp70 expression was observed trophoblast cells and decidual cells and was relatively constant throughout the pregnancy. This protein was strongly labeled in the trophoblast cells; while decidual cells were displayed moderate staining. In early pregnant mouse uteri, PCNA was mainly localized in decidual-stromal cells. The trophoblast cells and decidual cells displayed highly proliferative activity at the midgestational period. However there was a significant decrease in the percentage of PCNA positive cells in late gestation.
Assuntos
Proteínas de Choque Térmico HSP70/metabolismo , Placenta/metabolismo , Gravidez/metabolismo , Antígeno Nuclear de Célula em Proliferação/metabolismo , Animais , Proliferação de Células , Feminino , Idade Gestacional , Proteínas de Choque Térmico HSP70/análise , Imuno-Histoquímica , Camundongos/metabolismo , Placenta/química , Placenta/citologia , Antígeno Nuclear de Célula em Proliferação/análise , Trofoblastos/química , Trofoblastos/metabolismoRESUMO
The effects of experimentally induced high incubation temperature on the embryonic development of growth plate of the chicken were investigated by means of histological and enzyme histochemical methods. In the experiments, 250 fertile eggs of Ross-308 broiler strain were divided into two groups, the control eggs were maintained under optimal conditions (37.8°C and 65% ± 2% relative humidity, rh) during the whole incubation period. Heat-stress imposed eggs were maintained under normal conditions (37.8°C and 65% ± 2% rh) until the 10th day of incubation, and then, continuously (24 h per day) exposed to high temperature (38.8°C and 65% ± 2% rh). Tissue samples were taken from 10 animals of each group at the 11th, 13th, 15th, 18th, 21st days of incubation. Tissue samples were processed by enzyme histochemical methods in addition to routine histological techniques. The relative tibia weights and tibia length were lower in the heat-stress group compared to the control group. The results of the measurements of the growth plate showed that the proliferative zone was narrowed whereas, the transitional and hypertrophic zone were thickened in the heat stress group. Alkaline phosphatase (ALP) density was significantly decreased in the heat-stress group compared to the control group. In conclusion, bone formation and growth plate formation are crucial for embryo development and 1°C higher from optimum may increase the incidence of skeletal disorders and leg problems in broiler chickens which is one of the major animal welfare concerns for the poultry industry.
Assuntos
Embrião de Galinha/embriologia , Lâmina de Crescimento/embriologia , Tíbia/embriologia , Animais , Embrião de Galinha/química , Feminino , Lâmina de Crescimento/química , Histologia , Temperatura Alta , Masculino , Tíbia/químicaRESUMO
In this study, embryotoxic effects of five commercially available dental alloys were investigated by using fertilized hens' eggs. One sample of each alloy was conditioned in one of the conditioning media, physiological saline (PS), 0.1 M phosphate-buffered saline (PBS, pH 7.4), and 0.1 M protein (3% bovine serum albumin, BSA) containing PBS (pH 6.8), respectively. The test solutions were injected into the fertilized hen's eggs via air sac at the beginning of the incubation. Various concentrations of a highly embryotoxic substance, AFB1, was also used as positive control test material. Mortality of the AFB1 treatment groups increased with increasing concentrations of AFB1 and the mortality values were significantly (p < 0.05) higher than those of the controls and eluent injected groups. The eluents of five commercially available dental alloys tested in the study did not have significant embryotoxic effects. Cu- and Pd-containing alloys displayed relatively high but statistically insignificant embryotoxic effects. Chick embryo might be used in determination of the embryotoxic effects of the dental alloys with its several advantages. Nevertheless, the test should be further standardized and new methods such as micronucleus test showing possible genotoxic effects of the materials should be used.
Assuntos
Ligas Dentárias/toxicidade , Embrião de Mamíferos/efeitos dos fármacos , Embrião não Mamífero , Zigoto/efeitos dos fármacos , Animais , Soluções Tampão , Embrião de Galinha , Ligas Dentárias/química , Injeções , Metais , Modelos Animais , MortalidadeRESUMO
OBJECTIVE: To evaluate the efficacy of topical administration of a 2% solution of cyclosporine (CsA) for treatment of dogs with keratoconjunctivitis sicca (KCS) and to correlate results with histopathologic characteristics and local cellular immunity of the gland of the third eyelid. ANIMALS: 24 dogs with bilateral KCS. PROCEDURE: Lacrimal secretion was measured, using Schirmer tear test (STT) strips. Leukocyte and T-lymphocyte subsets were determined in blood samples. Histopathologic changes as well as CD4+, CD8+, and alpha-naphthyl-acetate esterase-positive (ANAE+) lymphocytes were evaluated. RESULTS: Clinical signs resolved at the end of 1 month in conjunction with significantly increased STT values, compared with baseline values. Fifteen and 30 days after discontinuation of CsA treatment, a decrease was observed in STT values in both eyes; however, only values for the right eye were significantly different. There was a significant decrease in the number of lymphocytes and ANAE+ lymphocytes 15 and 30 days after discontinuation of CsA treatment, compared with baseline values. Differences were not observed in number of CD4+ lymphocytes among treatment groups. However, there was a significant decrease in number of CD8+ lymphocytes with reversal of the CD4+:CD8+ in both eyes after CsA treatment for 30 days, compared with the control group. Increased secretory activity and decreased lymphocyte infiltration were characteristic histopathologic findings. CONCLUSIONS AND CLINICAL RELEVANCE: Topical administration of a 2% solution of CsA was effective for the treatment of dogs with KCS. Strict follow-up monitoring is required after the cessation of treatment because of the possibility of recurrence of KCS.
Assuntos
Ciclosporina/uso terapêutico , Doenças do Cão/tratamento farmacológico , Imunossupressores/uso terapêutico , Ceratoconjuntivite Seca/veterinária , Administração Tópica , Animais , Biópsia/veterinária , Ciclosporina/administração & dosagem , Doenças do Cão/imunologia , Doenças do Cão/patologia , Cães , Feminino , Imunossupressores/administração & dosagem , Ceratoconjuntivite Seca/tratamento farmacológico , Ceratoconjuntivite Seca/imunologia , Ceratoconjuntivite Seca/patologia , Contagem de Linfócitos/veterinária , Subpopulações de Linfócitos/imunologia , Masculino , Naftol AS D Esterase/sangue , Membrana Nictitante/imunologia , Membrana Nictitante/patologia , Distribuição Aleatória , Lágrimas/metabolismoRESUMO
The aim of this study was to determine the effect of aflatoxin (AF) on spermatologic, biochemical, and testis parameters in rams, and the protective efficiency of esterified glucomannan (EG) co-administered with AF. Thirty-two Merino rams (12-14 months old) were used. The experimental design consisted of four dietary treatments. The control group was fed commercial feed. The AF group was fed with commercial feed plus 250 µg/d of total AF. The EG group received commercial feed plus 2 g/d of EG. The AF + EG group was given commercial feed plus 250 µg/d of total AF and 2 g/d of EG. There were treatment, time, and treatment-by-time interaction effects on sperm motility, abnormal spermatozoa, damaged acrosome, and dead spermatozoa (P < 0.01). The percentage of motile sperm was lower and the percentages of abnormal sperm, sperm with damaged acrosomes, and dead sperm were greater in the AF group than in the control, AF+EG, and EG groups, as from week 3 until the end of week 12 (P < 0.05). As from week 3, hyaluronidase activity in the seminal plasma increased significantly in the AF group, compared with the control. The co-administration of AF+EG was found to be effective in preventing the increase in hyaluronidase activity. As week 4, malondialdehyde (MDA) levels were significantly higher in the AF group compared with the control. The combined administration of AF+EG was found to be effective in lowering the MDA levels, increased by AF, to the levels measured in the control (P < 0.05). Although glutathione (GSH) levels were determined to have significantly decreased in the AF group in comparison to the control, it was observed that, in the group co-administered with AF and EG, particularly after week 7, the GSH levels, which had decreased owing to AF, were largely ameliorated (P < 0.05). In conclusion, AF adversely affected spermatologic, biochemical, and testis parameters, and the combined administration of EG with AF reversibly eliminated these adverse effects in rams.
Assuntos
Aflatoxinas/toxicidade , Mananas/farmacologia , Substâncias Protetoras/farmacologia , Sêmen/efeitos dos fármacos , Ovinos/fisiologia , Testículo/efeitos dos fármacos , Acrossomo/efeitos dos fármacos , Acrossomo/ultraestrutura , Ração Animal , Animais , Glutationa/metabolismo , Hialuronoglucosaminidase/metabolismo , Masculino , Malondialdeído/metabolismo , Sêmen/metabolismo , Motilidade dos Espermatozoides/efeitos dos fármacosRESUMO
The purpose of this study was to investigate the beneficial effects of particulate ostrich eggshell grafting on the healing of experimentally induced skull defects. The clinical, radiological, histological, and histomorphometrical findings of this material were compared with the results of commercially available demineralized bone matrix (DBM). The study was conducted on 18 adult New Zealand rabbits. One defect served as a control and the remaining ones either were filled with different sized eggshell particles or DBM, in each animal. Clinical and radiological inspections and histologic investigations of the animals were done at the 1st, 3rd, and 6th months of postoperative period. Radiologically, minimal bone regeneration was observed at the empty, control defect sites. The most advanced bone regeneration was in the DBM grafted defects. The eggshell particle grafted defect sites displayed weak bone regeneration at earlier stages, at 1st and 3rd months after operation when compared with demineralized bone matrix. Nevertheless, ossification was satisfactory at 6th month after operation when compared with the control defects. Within the limitations of this study, it was concluded that Ostrich eggshell powder (OSP) is a worth-while bone substitute because it is a safe, cheap, and easily available material. Long-term studies will clarify its possible role in maxillofacial surgery. Further sophisticated experiments should be undertaken before human implantation concerning its osteoproductive activity alone or in combination with other materials.