Adverse effect of beta-tricalcium phosphate with zeta potential control in repairing critical defects in rats' calvaria.

OBJECTIVE: To evaluate whether a new biphasic cement composed of calcium sulfate and beta tricalcium phosphate with zeta potential control could induce or lead to bone neoformation in critical defects. METHODS: A critical defect of diameter 8 mm was made in the calvaria of forty male Wistar rats. In the Test Group (n = 20), the defects were filled with cement. In the Control Group (n = 20), the defect was not filled and only coagulum was present. The animals were sacrificed 7, 14, 21 and 42 days after the operation. Calvaria specimens were subjected to microtomography and were then prepared for histological analysis. The analyses included morphological assessment on the histopathology of the repair; comparative morphometric evaluation of the area of formation of bone trabeculae between the groups; and histochemical staining by means of tartrate-resistant phosphatase (TRAP) in order to identify osteoclasts. RESULTS: Microtomographic images of the defects filled by the cement did not show any decrease in area over the course of postoperative evolution. In the Test Group, the material continued to present a foreign-body response until the last observational periods. Histomorphological analysis showed that there were more significant groupings of giant cells in the Test Group and greater maturity of neoformed bone in the Control Group. Exogenous material was also present. Histomorphometric analysis showed that in the Control Group, the total area of bone neoformation was significantly greater (p = 0.009) and grew progressively. The giant cells presented a positive reaction to TRAP but no osteoclasts were observed. CONCLUSION: The ceramic cement did not induce or lead to bone neoformation from the microtomographic or histological point of view.

OBJETIVO: Avaliar se um novo cimento bifásico composto por sulfato de cálcio e beta fosfato tricálcico com controle de potencial zeta poderia induzir ou conduzir a neoformação óssea em defeitos críticos. MÉTODOS: Foi feito um defeito crítico de 8 mm de diâmetro na calvária de 40 ratos Wistar machos. No grupo teste (n = 20) os defeitos foram preenchidos pelo cimento. No grupo controle (n = 20) os defeitos não foram preenchidos, permaneceu apenas o coágulo. Os animais sofreram eutanásia em 7, 14, 21 e 42 dias do pós-operatório. Espécimes da calvária foram microtomografados e posteriormente preparados para análise histológica. As análises incluíram a avaliação morfológica da histopatologia do reparo e a avaliação morfométrica da área de formação das trabéculas ósseas comparativamente entre os grupos e coloração histoquímica por meio da fosfatase tartrato-resistente (TRAP) para identificação de osteoclastos. RESULTADOS: As imagens microtomográficas dos defeitos preenchidos pelo cimento não apresentaram diminuição da área de acordo com a progressão dos períodos pós-operatórios. No grupo teste houve permanência do material e resposta corpo estranho até os últimos períodos de observação. A histomorfologia mostrou agrupamentos mais expressivos de células gigantes no grupo teste e osso neoformado mais maduro no grupo controle e comprovou a presença de material exógeno. Na histomorfometria, a área total de neoformação óssea foi significativamente maior (p = 0,009) e crescente no grupo controle. As células gigantes apresentaram expressão histoquímica positiva para TRAP e não foram observados osteoclatos. CONCLUSÃO: O cimento cerâmico não induziu ou conduziu a neoformação óssea sob o ponto de vista microtomográfico e histológico.

Adverse effect of beta-tricalcium phosphate with zeta potential control in repairing critical defects in rats' calvaria / Efeito adverso do beta-fosfato tricálcico com controle de potencial zeta no reparo de defeitos críticos em calvária de ratos

To evaluate whether a new biphasic cement composed of calcium sulfate and beta tricalcium phosphate with zeta potential control could induce or lead to bone neoformation in critical defects. METHODS: A critical defect of diameter 8 mm was made in the calvaria of forty male Wistar rats. In the Test Group (n = 20), the defects were filled with cement. In the Control Group (n = 20), the defect was not filled and only coagulum was present. The animals were sacrificed 7, 14, 21 and 42 days after the operation. Calvaria specimens were subjected to microtomography and were then prepared for histological analysis. The analyses included morphological assessment on the histopathology of the repair; comparative morphometric evaluation of the area of formation of bone trabeculae between the groups; and histochemical staining by means of tartrate-resistant phosphatase (TRAP) in order to identify osteoclasts. RESULTS: Microtomographic images of the defects filled by the cement did not show any decrease in area over the course of postoperative evolution. In the Test Group, the material continued to present a foreign-body response until the last observational periods. Histomorphological analysis showed that there were more significant groupings of giant cells in the Test Group and greater maturity of neoformed bone in the Control Group. Exogenous material was also present. Histomorphometric analysis showed that in the Control Group, the total area of bone neoformation was significantly greater (p = 0.009) and grew progressively. The giant cells presented a positive reaction to TRAP but no osteoclasts were observed. CONCLUSION: The ceramic cement did not induce or lead to bone neoformation from the microtomographic or histological point of view.

Avaliar se um novo cimento bifásico composto por sulfato de cálcio e beta fosfato tricálcico com controle de potencial zeta poderia induzir ou conduzir a neoformação óssea em defeitos críticos. MÉTODOS: Foi feito um defeito crítico de 8 mm de diâmetro na calvária de 40 ratos Wistar machos. No grupo teste (n = 20) os defeitos foram preenchidos pelo cimento. No grupo controle (n = 20) os defeitos não foram preenchidos, permaneceu apenas o coágulo. Os animais sofreram eutanásia em 7, 14, 21 e 42 dias do pós-operatório. Espécimes da calvária foram microtomografados e posteriormente preparados para análise histológica. As análises incluíram a avaliação morfológica da histopatologia do reparo e a avaliação morfométrica da área de formação das trabéculas ósseas comparativamente entre os grupos e coloração histoquímica por meio da fosfatase tartrato-resistente (TRAP) para identificação de osteoclastos. RESULTADOS: As imagens microtomográficas dos defeitos preenchidos pelo cimento não apresentaram diminuição da área de acordo com a progressão dos períodos pós-operatórios. No grupo teste houve permanência do material e resposta corpo estranho até os últimos períodos de observação. A histomorfologia mostrou agrupamentos mais expressivos de células gigantes no grupo teste e osso neoformado mais maduro no grupo controle e comprovou a presença de material exógeno. Na histomorfometria, a área total de neoformação óssea foi significativamente maior (p = 0,009) e crescente no grupo controle. As células gigantes apresentaram expressão histoquímica positiva para TRAP e não foram observados osteoclatos. CONCLUSÃO: O cimento cerâmico não induziu ou conduziu a neoformação óssea sob o ponto de vista microtomográfico e histológico.

Repair of Critical Calvarias Defects With Systemic Epimedium sagittatum Extract.

It is well established in reconstructive surgery the repair of great bone defects is a difficult goal to be achieved. The aim of this study was to evaluate the influence of an extract rich in icariin on bone neoformation in critically sized defects in rat calvaria. Under continual saline irrigation, a circular bone defect was created in 40 rat calvarias with an 8-mm diameter trephine drill. Animals were randomly divided into a test group that received an Epimedium sagittatum extract (containing 5.8 mg/mL of icariin) and a control group that received an equal volume of saline solution. Substances were administered daily through a feeding tube until euthanasia. After 7, 14, 21, and 42 days, 5 animals from each group were euthanized. Calvaria defect samples were fixed in 10% formalin for 48 hours, X-rayed, and histologically processed. In the test group, there was a significant reduction in the bone defect area on X-ray images and an increase in new bone area in all of the experimental periods in the test group. At 42 days, the bone in the test group also exhibited a significant reduction in osteocyte (P = 0.002) and osteoclast density (P = 0.041). The authors conclude that administration of systemic Epimedium extracts containing high concentrations of icariin can induce bone neoformation and reduce osteocyte and osteoclast densities, thereby altering the normal deposition and remodeling patterns that are present in critically sized bone defects.

Can the use of antibiotics interfere with the success of dental osseointegrated implants in diabetic patients?

AIM: The present review aims to discuss the last 10 years published data on the topic of the use of osseointegrated implants in diabetic subjects, particularly regarding the influence of antibiotics administration in the perioperative period. BACKGROUND: In the last decades, oral rehabilitation significantly has evolved particularly with the use of osseointegrated implants. Increased life expectation of population is reflecting in a greater number of diabetic patients who might require dental osseointegrated implants rehabilitation. Diabetes was considered for a long time as a contraindication for oral implant placement. In this context, the use of antibiotics is still a controversial factor when we correlate it to implant success rate. REVIEW RESULTS: Although 228 articles were initially selected for evaluation of proposed criteria, only 16 articles were considered valid. Among the 16 selected articles, only six articles represented clinical research that discussed the influence of the antibiotic in the success of osseointegration of dental implants in diabetic subjects. Five were retrospective studies and one a prospective research. CONCLUSION: Data favors the use of antibiotics without significant side effects but clinical investigations of the need of prophylaxis antibiotic or therapeutic antibiotics are still scarce. The lack of adequate methodology is one of the main problems of the current articles. It is important to emphasize that studies should present detailed methodology in order to allow reproducibility. CLINICAL SIGNIFICANCE: Permanent tooth loss is a pathological condition that affects millions of people worldwide. The possibility of successful treatment of edentulous areas through osseointegrated implants in those systemic compromised patients is a matter of scientific discussion. Although antimicrobial agents must be used rationally and carefully to avoid development of bacterial resistance, more studies are needed in order to support evidence regarding the influence of antibiotics in the success of dental implant surgery in diabetic patients.

Avaliação da reparação de defeitos ósseos críticos na calvária de ratos Wistar sob ação sistêmica de Icariin: estudo radiográfico, histomorfológico e histomorfométrico / Evaluation of calvaria critical size defects healing in Wistar rats induced by systemic Icariin: a radiographic, histomorphologic and histomorphometric study

A reconstrução de defeitos ósseos críticos é alvo de inúmeras pesquisas em cirurgia bucomaxilofacial. Tais pesquisas visam, de maneira geral, a optimização da neoformação óssea e a eliminação dos procedimentos de remoção de osso autógeno para reconstrução. Os modelos animais têm sido a metodologia mais utilizada para avaliar a eficácia de novas substâncias e biomateriais na reparação óssea. O objetivo desta pesquisa foi avaliar a influência de um flavonóide, o icariin, na reparação óssea de defeitos críticos confeccionados na calvária de ratos Wistar. Um defeito ósseo crítico circular foi confeccionado em 40 calvarias de ratos por meio de uma broca trefina de 8 mm de diâmetro sob irrigação salina constante. Ao final dos procedimentos cirúrgicos, os animais foram divididos, aleatoriamente, em grupo teste (n=20), que recebeu o icariin, na dose de 125 mg/kg de peso e grupo controle (n=20), que recebeu soro fisiológico. Ambas as substâncias foram administradas por meio de gavagem até o dia da eutanásia. Ao final de cada período observacional de 7, 14, 21 e 42 dias, 5 animais de cada grupo foram eutanasiados e as amostras da calvária foram removidas e mantidas em formol 10% por 48 horas.

As calvárias foram radiografadas e, após descalcificação, foram submetidas à avaliação histológica com coloração hematoxilina-eosina sob microscópio de luz. Os defeitos foram analisados considerando a diminuição da área do defeito na imagem radiográfica, as características de reparo ósseo e a osteogênese na região da ferida. Os resultados da análise radiográfica mostraram que a área do defeito ósseo no grupo teste foi significativamente menor que no grupo controle em todos os períodos observacionais. A avaliação histológica mostrou um aumento na neoformação óssea do grupo teste (p=0,02). A histomorfometria demonstrou osteogênese significante no grupo teste com 7 dias (p=0,021), 14 dias (p=0,014), 21 dias (p=0,021) e 42 dias (p=0,009). Foi possível concluir que o icariin sistêmico induziu uma maior neoformação óssea em defeitos críticos.

Bone critical defect reconstruction is an important target in current oral surgery research. Contemporary research has been searching for osteogenesis optimization to minimize the necessity of using autogenous bone grafts procedures. Animal models have been the widespread methodology to evaluate the effect of different new substances and biomaterials in bone healing. The aim of this study was to assess the influence of systemic daily flavonoid, icariin, in the repair of calvaria critical size defects induced in Wistar rats. A round critical size defect was performed centrally in 40 rats calvaria using an 8mm trephine under sterile saline solution irrigation. After surgery, half the animals, randomly, received by gavage daily doses of 125mg/Kg-icariin (Test Group) till the euthanasia. The other half (Control Group) received the same volume of saline solution. Five animals of each group were euthanized after 7, 14, 21 and 42 days postoperatively. The rats calvaria were removed, fixed in 10% formalin for 48 hours. Calvarias were X-rayed and after decalcification they underwent histological examination with hematoxylin eosin stain under a light microscope. Defects were analyzed considering area diminishing in X-ray image, bone healing characteristics and osteogenesis in the defect region. Results showed that bone defect area in Test Group was significant smaller in all observational periods. Histological evaluation showed an increased expression in bone trabeculae neoformation in Test Group (p=0,02). Histomorphometry demonstrated significant osteogenesis in Test Group at 7 days (p=0,021), 14 days (p=0,014), 21 days (p=0,021) and 42 days (p=0,009). It was concluded that systemic icariin induced a more expressive bone healing in critical size defects in rats.

A comparative study of the physical properties of conventional and Grander-modified adhesive systems / Estudo comparativo das propriedades físicas de sistemas adesivos convencional e Grander-modificado

PURPOSE: The objective of this study was to evaluate the influence of the Grander technology in reducing the surface tension and contact angle of a self-etch adhesive system. METHODS: Distilled water and Xeno III self-etch adhesive system (Dentsply) were modified by physical contact with the Flexible unit Grander system to revitalize water, for 48 hours, resulting in four groups: Group 1 - Xeno III under normal conditions; Group 2 - Xeno III modified by Grander; Group 3 - distilled water under normal conditions; Group 4 - distilled water system modified by the Grander system;. Surface tension and contact angle (dentin substrate and titanium plate) of the adhesive system and water in normal and Grander-modified conditions was measured with a goniometer. Data were analyzed by ANOVA and Tukey test (5%). RESULTS: Grander technology reduced the surface tension of water but not of the adhesive system Xeno III. The contact angle property of the adhesive ystem was not affected. CONCLUSION: Grander technology did not interfere with the surface tension and contact angle physical properties of the Xeno III self-etch adhesive system.

OBJETIVO: Esta pesquisa verificou os efeitos da tecnologia Grander na alteração da tensão superficial e ângulo de contato de um sistema adesivo autocondicionante. METODOLOGIA: O sistema adesivo autocondicionante Xeno III (Dentsply) e a água destilada foram modificados pelo contato físico com a unidade flexible do sistema Grander para revitalização de águas por 48 horas, resultando em 4 grupos: Grupo 1 - sistema adesivo Xeno III em condições de normalidade; Grupo 2 - sistema adesivo Xeno III modificado pelo sistema Grander; Grupo 3 - água destilada em condições de normalidade; Grupo 4 - água destilada modificada pelo sistema Grander. A tensão superficial dos líquidos foi verificada em goniômetro utilizando cinco medidas para cada gota de líquido. O ângulo de contato foi medido com o goniômetro sobre os substratos placa de titânio e dentes bovinos. Os dados foram submetidos aos testes ANOVA e Tukey (5%). RESULTADOS: Houve redução significativa da tensão superficial da água com a modificação pelo sistema Grander. Não houve redução da tensão superficial e ângulo de contato para o sistema adesivo Xeno III. CONCLUSÃO: A tecnologia Grander não interferiu com a tensão superficial e o ângulo de contato para o sistema adesivo Xeno III.

Exfoliative cytology of the oral mucosa: comparison of two collection methods.

This study compared the sampling efficacy of a cytobrush and metal spatula for exfoliative cytology of the oral mucosa. Thirty students with no detectable oral alterations upon clinical examination were submitted to exfoliative cytology of the lateral border of the tongue, using a metal spatula on the left side and a cytobrush on the right side. The smears were stained using the Papanicolaou technique and evaluated for cellularity, cell type, cell distribution, homogeneity, and cellular distortion, as well as the presence of mucus, inflammatory infiltrate, and hemorrhage. A statistical test (Z-test) with a 95% confidence interval (CI) showed a significant difference between the metal spatula and cytobrush in terms of cellularity (p = 0.02) and homogeneity (p = 0.01). No difference between the two methods was observed regarding cell type (p = 0.4, Z-test) or cell distribution for the 95% confidence interval (p = 0.2, Fisher's test). Cell distortion and the presence of mucus were observed in five cases that used the metal spatula and in two cases that used the cytobrush. No hemorrhage or inflammatory infiltrate was detected in any of the slides. Based on the results of this study, the cytobrush produced qualitatively better smears in terms of cellularity and homogeneity compared to the metal spatula.