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Introdução: Diferentes metodologias tem sido utilizadas para avaliação histológica da osseointegração, levando a diferentes resultados. Objetivo: O objetivo é comparar diferentes metodologias de análise histomorfométrica da osseointegração de implantes com diferentes superfícies, instalados em tíbias de ratos. Material e método: 24 ratos foram aleatoriamente divididos em 3 grupos (n = 8) para a instalação dos implantes. Esses grupos foram divididos de acordo com o tipo de implante instalado na tíbia: Grupo Hidrofílico - HFL (instalação de implante com superfície modificada por jateamento de óxidos e ataque ácido e mantida em solução de cloreto de sódio), Grupo Hidrofóbico - HFB (instalação de implante com superfície modificada por jateamento de óxidos e ataque ácido) e Grupo Usinado - U (instalação de implante com superfície usinada). No período de 45 dias após os procedimentos cirúrgicos de instalação dos implantes, os animais foram submetidos à eutanásia, e as tíbias foram removidas, sendo realizado o processamento histológico para amostras não descalcificadas. Após a obtenção das lâminas, foi realizada a análise histomorfométrica para avaliar as porcentagens de contato osso-implante (% BIC) e da área óssea entre as espiras (% BBT). As mensurações foram realizadas em duas diferentes regiões: 1) as roscas do implante na região do osso cortical e 2) todas as roscas do implante inseridas no osso (cortical e medular). A análise estatística foi feita por meio de ANOVA One-Way, seguida pelo teste de Tukey para análise inferencial dos dados. Resultado: Quando o BIC e o BBT foram analisados de forma independente nas regiões cortical e trabecular/total, observou-se uma diferença no comportamento histológico dos implantes de acordo com o tratamento de superfície. Os implantes HFL apresentaram BIC (%) trabecular 16,85% maior (p = 0,02) do que os implantes HFB e 26,12% maior (p ≤ 0,0001) do que os implantes usinados. Contudo, a região cortical de todos os grupos apresentou valores de BIC cortical significativamente maiores ao redor dos implantes, independentemente da superfície. Conclusão: Os resultados obtidos demonstraram que a formação óssea peri-implantar foi superior nas análises realizadas apenas em osso cortical, se comparados aos valores obtidos na mensuração total (osso cortical somado ao medular). Também foi possível observar que, dentro da mesma superfície, os valores de BIC (%) foram superiores em osso cortical. Em relação às limitações do estudo, pode-se concluir que diferentes metodologias de análise histométrica da osseointegração ao redor de diferentes superfícies de implantes instalados em tíbias de ratos podem interferir nos resultados de osseointegração, independentemente da superfície analisada.
Introduction: Different methodologies were used for histological evaluation of osseointegration, leading to different results. Objective: The objective is to compare different methodologies for histomorphometric analysis of the osseointegration of implants with different surfaces, installed in rat tibias. Material and method: Twenty-four rats were randomly divided into 3 groups (n=8) for implant installation. These groups were divided according to the type of implant that will be installed in the tibia: Hydrophilic Group (installation of an implant with a surface modified by oxide blasting and acid attack and maintained in a sodium chloride solution), Hydrophobic Group (installation of an implant with surface modified by oxide blasting and acid attack) and Machined Group (implant installation with machined surface). Within 45 days after the surgical procedures to install the implants, the animals were euthanized and the tibias were removed, and histological processing was carried out for non-decalcified samples. After obtaining the slides, histomorphometric analysis was performed to evaluate the percentages of bone-implant contact (%BIC) and the bone area between the turns (%BBT). Measurements were carried out in two different regions: 1) the implant threads in the cortical bone region and 2) all implant threads inserted into the bone (cortical and medullary). Statistical analysis was performed using One-Way ANOVA followed by Tukey's test for inferential data analysis. Result: The BIC and BBT were analyzed independently in the cortical and trabecular/total regions, a difference was observed in the histological behavior of the implants according to the surface treatment. HFL implants showed trabecular BIC (%) 16.85% higher (p=0.02) than HFB implants and 26.12% higher (p≤0.0001) than machined implants. However, the cortical region of all groups showed significantly higher cortical BIC values around the implants, regardless of the surface. Conclusion: the results obtained demonstrated that peri-implant bone formation was superior in analyzes carried out only on cortical bone, compared to the values obtained in the total measurement (cortical bone plus medullary bone). It was also possible to observe that, even within the same surface, the BIC(%) values were higher in cortical bone. Within the limitations of the study, it can be concluded that different methodologies for histometric analysis of osseointegration around different surfaces of implants installed in rat tibias can interfere with the results of osseointegration regardless of the surface analyzed
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Ratas , Tibia , Huesos , Implantes Dentales , Interpretación Estadística de Datos , Oseointegración , Boca Edéntula , Análisis de VarianzaRESUMEN
Background: The thymus is one of the primary lymphoid organs other than being the bone marrow. It is responsible for the provision of thymus-processed lymphocytes (T lymphocytes) to the whole body. Aim of the study: To study the microscopic architecture of the cortex and medulla, structure and type of epithelial cells, nature of connective tissue stroma, vasculature of thymus organ, the morphology of Hassall Corpuscle (HC). To study the histometric analysis like estimation of volume and diameter of HC at various gestational age. Method: Total 20 aborted and still born fetuses ranging from 17-39 weeks of gestation were used for the study. After embalming, meticulous dissection, thymus gland was weighed and fixed with formalin. The various histological and histometric parameters were observed. Results: The cortex and medulla were well demarcated by the 17th week. The weight and volume of the thymus were proportionately increased as the fetal age advanced. Early phase had thick mucoid interlobular septae whereas the later phase had thin, reticular interlobular septae. Four different types of HC (SHC, CHC I, CHC II and DHC) in fetus were seen. The presence of solid HC at the periphery of the medulla and degenerating HC at the central core of the medulla tends to postulate the direction of maturation which is from the periphery to the center of the medulla. Conclusion: The findings of the present study is in conformity with studies related to the volume and size of the thymus with respect to gestational ages and histological features related to parenchymal and mesenchymal tissue composition and its various components. However, the present study noted different types of Hassall’s Corpuscles which are reported in the adult thymus and the findings lead to further discussion on the maturation and differentiation of Hassall’s Corpuscles in human fetal thymus.
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Objectives: Odontogenic keratocysts are common, locally destructive lesions of the head and neck region. They can occur as solitary or multiple lesions, and if multiple, they are mostly associated with Gorlin-Goltz syndrome. This study aims to categorize the OKCs which behave more aggressively, using conventional histopathological techniques. Methodology: The present study exploits conventional histopathological techniques to gain an insight into the behavior of the OKC (both solitary and non-syndrome associated multiple OKCs). The histological features (keratinization pattern, presence of satellite cysts / odontogenic islands, epithelial infoldings and corrugations) and histometric parameters (total number of nuclei, epithelial height, total nuclear density, number of basal nuclei, basement membrane length, basal nuclear density and mitotic index) were compared between the two groups of cysts. Result: Multiple OKCs exhibited increase in number of infoldings, corrugations, mitotic index, reduced epithelial height, total number of nuclei, number of basal nuclei, and basal nuclear density. This information may be used to predict their biologic behavior and thus serve as a basis for diagnostic and therapeutic strategies. Conclusion: Conventional histopathological techniques can provide valuable information which may be useful to categorize those OKCs that have more aggressive biological behavior and helps in deciding the treatment protocol.
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Proposição: O objetivo deste estudo foi comparar o comportamento biológico e mecânico do tecido ósseo ao redor de implantes de superfícies comerciais modificada por condicionamento ácido (SA), e usinada (SU), com implantes de superfícies experimentais modificada por laser (SL), e modificada por laser com depósito de sílica (SS), empregando-se as análises biomecânica, topográfica e histométrica. Material e Métodos: Trinta coelhos receberam 120 implantes de 3,75x10mm em suas tíbias direita e esquerda, sendo dois implantes de cada superfície por tíbia. O implante localizado mais superior, instalado na metáfise tibial foi utilizado para o ensaio biomecânico, descrito no capítulo I; e o implante localizado abaixo deste, instalado na epífise tibial foi utilizado para o estudo histométrico, descrito no capítulo II. A morfologia das superfícies dos implantes foi analisada por microscopia eletrônica de varredura (MEV), e por espectroscopia de energia dispersiva de raios X (EDS) antes, e após 4 semanas de implantação e remoção por torque reverso. Medidas de rugosidade e secção transversal foram obtidas. Após períodos de 4, 8, e 12 semanas realizou-se o ensaio biomecânico, e após os animais sofreram eutanásia. As peças do implante localizado na epífise tibial foram levadas ao micrótomo para corte sem descalcificação. A análise histométrica foi realizada empregando-se microscopia óptica. Foi mensurada a extensão linear de contato entre osso e implante (ELCOI), e a área óssea (AO). Uma lâmina de cada superfície do período de 4 semanas foi metalizada para realização da análise do mapeamento elementar por MEV-EDS. Resultados: A caracterização topográfica mostrou diferenças entre as superfícies analisadas, e os valores de rugosidade média das SL e SS foram estatisticamente superiores (p<0,05) a SA. Na comparação estatística dos valores obtidos pelo ensaio biomecânico, verificou-se em 4 semanas que os implantes SS e SL apresentaram torque de remoção superior (p<0,05) aos SU e...
Purpose: The aim of this study was to compare the biologic and mechanical behavior of bone tissue around implants with commercially available surfaces, modified by acid etching (SA), and machined surfaces (SU), with the experimental surfaces modified by laser (SL), and modified by laser with silica deposition (SS), using biomechanical, topographic and histometric analyses. Materials and Methods: Thirty rabbits received 120 implants measuring 3,75x10mm in their right and left tibias, being two implants of each type of surface per tibia. The implant located in the uppermost position, inserted in the tibial metaphysis, was used for the biomechanical test, described in Chapter I; and the implant located below this, inserted in the tibial epiphysis, was used for the histometric study, described in Chapter II. The morphology of the implant surfaces was analyzed by scanning electron microscopy (SEM) and by energy dispersive X-ray spectrometry (EDS) before and after 4 weeks of implantation and removal by reverse torque. Mean roughness and cross-sectional measurements were obtained. After periods of 4, 8, and 12 weeks the biomechanical test was performed, and after this the animals were euthanized. The parts of the implant located in the tibial epiphysis were taken for cutting nondecalcified on a microtome. Histometric analysis was performed using an optical microscope. The bone interface contact (BIC), and the bone area (AO) were measured in percentages. A slide of each surface in the period of 4 weeks was metalized in order to analyze the element mapping by means of SEM-EDS. Results: The topographic characterization showed differences between the analyzed surfaces, and the mean roughness values of SL and SS were statistically higher (p<0,05) than those of SA. In the statistical comparison of the values obtained by the biomechanical test, it was verified that at 4 weeks the implants SS and SL presented a higher removal torque (p<0,05) than SU and SA. At 8 weeks the...
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Animales , Conejos , Materiales Biocompatibles , Implantes Dentales , Rayos Láser , Oseointegración , Torque , ConejosRESUMEN
Proposição: O objetivo deste estudo foi comparar o comportamento biológico e mecânico do tecido ósseo ao redor de implantes de superfícies comerciais modificada por condicionamento ácido (SA), e usinada (SU), com implantes de superfícies experimentais modificada por laser (SL), e modificada por laser com depósito de sílica (SS), empregando-se as análises biomecânica, topográfica e histométrica. Material e Métodos: Trinta coelhos receberam 120 implantes de 3,75x10mm em suas tíbias direita e esquerda, sendo dois implantes de cada superfície por tíbia. O implante localizado mais superior, instalado na metáfise tibial foi utilizado para o ensaio biomecânico, descrito no capítulo I; e o implante localizado abaixo deste, instalado na epífise tibial foi utilizado para o estudo histométrico, descrito no capítulo II. A morfologia das superfícies dos implantes foi analisada por microscopia eletrônica de varredura (MEV), e por espectroscopia de energia dispersiva de raios X (EDS) antes, e após 4 semanas de implantação e remoção por torque reverso. Medidas de rugosidade e secção transversal foram obtidas. Após períodos de 4, 8, e 12 semanas realizou-se o ensaio biomecânico, e após os animais sofreram eutanásia. As peças do implante localizado na epífise tibial foram levadas ao micrótomo para corte sem descalcificação. A análise histométrica foi realizada empregando-se microscopia óptica. Foi mensurada a extensão linear de contato entre osso e implante (ELCOI), e a área óssea (AO). Uma lâmina de cada superfície do período de 4 semanas foi metalizada para realização da análise do mapeamento elementar por MEV-EDS. Resultados: A caracterização topográfica mostrou diferenças entre as superfícies analisadas, e os valores de rugosidade média das SL e SS foram estatisticamente superiores (p<0,05) a SA. Na comparação estatística dos valores obtidos pelo ensaio biomecânico, verificou-se em 4 semanas que os implantes SS e SL apresentaram torque de remoção superior (p<0,05) aos SU e...
Purpose: The aim of this study was to compare the biologic and mechanical behavior of bone tissue around implants with commercially available surfaces, modified by acid etching (SA), and machined surfaces (SU), with the experimental surfaces modified by laser (SL), and modified by laser with silica deposition (SS), using biomechanical, topographic and histometric analyses. Materials and Methods: Thirty rabbits received 120 implants measuring 3,75x10mm in their right and left tibias, being two implants of each type of surface per tibia. The implant located in the uppermost position, inserted in the tibial metaphysis, was used for the biomechanical test, described in Chapter I; and the implant located below this, inserted in the tibial epiphysis, was used for the histometric study, described in Chapter II. The morphology of the implant surfaces was analyzed by scanning electron microscopy (SEM) and by energy dispersive X-ray spectrometry (EDS) before and after 4 weeks of implantation and removal by reverse torque. Mean roughness and cross-sectional measurements were obtained. After periods of 4, 8, and 12 weeks the biomechanical test was performed, and after this the animals were euthanized. The parts of the implant located in the tibial epiphysis were taken for cutting nondecalcified on a microtome. Histometric analysis was performed using an optical microscope. The bone interface contact (BIC), and the bone area (AO) were measured in percentages. A slide of each surface in the period of 4 weeks was metalized in order to analyze the element mapping by means of SEM-EDS. Results: The topographic characterization showed differences between the analyzed surfaces, and the mean roughness values of SL and SS were statistically higher (p<0,05) than those of SA. In the statistical comparison of the values obtained by the biomechanical test, it was verified that at 4 weeks the implants SS and SL presented a higher removal torque (p<0,05) than SU and SA. At 8 weeks the...
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Animales , Conejos , Materiales Biocompatibles , Implantes Dentales , Rayos Láser , Oseointegración , Torque , ConejosRESUMEN
As ambient temperature and humidity are high all year round within clearly defined dry and rainy seasons in our humid tropical environment, we evaluated the effects of season on the histometric characteristics of the reproductive organs of pubertal West African dwarf bucks using 8 healthy animals. There were no significant differences (p>0.05) between the rainy and dry seasons in the basement membrane of the testes, seminiferous tubular diameter, and round spermatid nuclear diameter. There were also similarities (p>0.05) between the seasons in epididymal luminal diameters, epididymal epithelial heights as well as in Leydig/sertoli cell ratio and sertoli cell Índex. Quadratic regression analyses showed that all the histometric characteristics of the testes are highly predictable from the live weights of the animals. It is concluded from these results that the WAD goat would not have a restricted breeding season in it native tropical environment. Young sires could therefore be selected early in life for planned improvement programmes in research institutions and breeding centers thus providing farmers with quicker returns for their investments.
Como la temperatura ambiental y la humedad son altas durante todo el año dentro de estaciones secas y lluviosas claramente definidas en nuestro ambiente húmedo tropical, se evaluaron los efectos de las estaciones en la características histométricas de los órganos reproductivos de cabras enanas machos púber del Africa Occidental, usando 8 animales sanos. No hubo diferencias significativas (p> 0,05) entre las estaciones de lluvia y secas, en la membrana basal de los testículos, diámetro de los túbulos seminíferos, y el diámetro de la envoltura nuclear espermática. Sin embargo, hubo similitudes (p> 0,05) entre las diferentes estaciones en el diámetro luminal del epidídimo, altura del epitelio del epidídimo, así como en la proporción de células Leydig/Sertoli e índice de células de Sertoli. El análisis de regresión cuadrática mostró que todas las características histométricas de los testículos son altamente predecibles desde el peso de los animales vivos. Se concluye de estos resultados, que las cabras enanas del Africa Occidental no tendrían una restricción estacional para tener crías en el ambiente tropical nativo. Padres jóvenes por lo tanto, podrían ser seleccionados tempranamente en la vida para programas de mejora planeados en instituciones de investigación y centros criadores los que provean a granjeros de rápidos retornos por sus inversiones.
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Animales , Cabras/anatomía & histología , Estaciones del Año , Testículo/anatomía & histología , Agricultura , Cabras/fisiología , Ambiente , Epidídimo/anatomía & histología , Nigeria , Tamaño de los Órganos , Reproducción , Zona Tropical , Testículo/fisiología , Túbulos Seminíferos/anatomía & histologíaRESUMEN
The most accurate method to assess bone level is the histometric measurement. However it causes discomfort in patients and damage to the regenerated tissues. in the present study, we used 4 type regenerative therapies. The present study evaluated the clinical reliability and accuracy of bone probing measurements and radiographic bone level in the assessment of bone level by comparing those results with histometric confirmed bone level. Twentyfour(24) intrabony defects(4x4mm 1-wall intrabony defects) were surgically created in the mandibular second and fourth premolars of 6 beagle dogs. The control group underwent a conventional flap operation. Experimental group 1 was treated with calcium phosphate glass only, and while experimental group 2 was treated with GTR and experimental group 3 was treated with calcium phosphate glass and GTR. The subjects were sacrificed 8 weeks after the operation and a bone probing measurements, radiographic measurement and histometric measurement was performed. The correlation between bone probing measurements(BP) and histometric measurement(HL), and radiographic measurement(RL) and histometric measurement(HL) were analyzed with Spearman's rank correlation analysis and the statistical significance with respect to the type of regenerative therapies was analyzed with the Kruskal Wallis test. The coefficeint of correlation to HL was 0.73 for RL and 0.90 for BP. The type of regenerative therapies had no significant effect on the difference between HL and other measurements. The results of this study suggests that bone probing measurements most closely represents actual bone level. So bone probing measurements may be a good clinical method for assessing the bone level following any type of periodontal regenerative therapies.