Does low-intensity pulsed ultrasound accelerate phasic calcium phosphate ceramic-induced bone formation?

Purpose: Low-intensity pulsed ultrasound (LIPUS) has been used to stimulate the healing of the fresh fracture, delayed union, and non-union in both animal and clinical studies. Besides, biphasic calcium phosphate ceramic (BCP) is a promising biomaterial for bone repair as it shows favorable biocompatibility, osteoinduction, and osteoconduction. However, scarcity is known about the combined effect of LIPUS and BCP on bone formation. Methods: The combined effect of LIPUS and BCP was studied in a beagle model. Twelve dogs were used. BCP granules without any additions were implanted into bilateral erector spinae muscles. One side is the BCP group, while the counterlateral side is LIPUS + BCP group. Histological and histomorphometric analyses, and quantitative real-time polymerase chain reaction were evaluated. Results: Compared with BCP alone, the LIPUS + BCP showed no advantages in early bone formation. Furthermore, the Notch signaling pathway-related mRNA has no significant difference between the two groups. Conclusions: The preliminary results showed that the BCP, which has intrinsic osteoinduction nature, was an effective and promising material. However, LIPUS has no enhanced effect in BCP induced ectopic bone formation. Furthermore, LIPUS has no effect on the Notch signaling pathway. Whether costly LIPUS could be used in combination with BCP should be a rethink.

Absorción mineral y retención ósea en ratas normales en crecimiento por el consumo de un yogur experimental reducido en lactosa que contiene galactooligosacáridos (GOS) / Mineral absorption and bone retention in normal growing rats by consumption of an experimental lactose-reduced yogurt containing galactooligosaccharides (GOS)

Introducción: Los GOS son prebióticos naturales presentes en la leche materna que pue-den obtenerse enzimáticamente a partir de la lactosa de leche de vaca durante la fabricación de yogur. El producto lácteo resultante será reducido en lactosa y contendrá prebióticos y bacterias potencialmente probióticas. Sin embargo, mantendrá la baja relación Ca/Pi que aporta la leche de vaca, lo que podría alterar el remodelamiento óseo y la mineralización. Objetivo: comparar si un yogur reducido en lactosa que contiene GOS (YE) ofrece ventajas adicionales respecto de un yogur regular sin GOS (YR) sobre las absorciones (Abs) de Ca y Pi, retención y calidad ósea durante el crecimiento normal. Al destete, ratas machos fueron divididas en 3 grupos alimentados con AIN ́93-G (C), YE o YR durante 28 días. Resultados: YE mostró el mayor aumento de lactobacilos fecales; producción de ácidos grasos de cadena corta especialmente p, profundidad de las criptas colónicas y menor pH cecal. El %AbsCa y %AbsPi aumentó en el siguiente órden: YE> YR> C (p < 0,05). El contenido de Ca y Pi en fémur, la densidad y contenido mineral óseos y los parámetros biomecánicos fueron similares en YE y C, mientras que YR mostró valores significativa-mente menores (p < 0,05). Conclusiones: YE aumentó las Abs y biodisponibilidad de minerales, alcanzando la retención y calidad ósea de C. El aumento en las Abs observado en YR no logró obtener la retención y calidad ósea de C. Conclusión: YE habría contrarrestado el efecto negativo del mayor aporte de Pi de la leche de vaca y sería una buena estrategia para lograr el pico de masa ósea y calidad del hueso adecuados, especialmente en individuos intolerantes a la lactosa. (AU)

Breast milk contains an optimal calcium/phosphate (Ca/Pi) ratio and GOS. These natural prebiotics can be enzymatically produced via cow's milk lactose inyogurt manufacture. This milk product is low in lactose and contains prebiotics and potentially probiotic bacteria but maintains a low Ca/Pi ratio that could alter bone remodeling and mineralization. We evaluated if a lactose-reduced yogurt containing GOS (YE) offers additional advantages over regular yogurt without GOS (YR) on Ca and Pi absorption (Abs), bone retention and quality during normal growth. Weaning male rats were divided into 3 groups fed AIN'93-G (C), YE or YR for 28 days. Results: YE showed the highest increase in fecal lactobacilli; short-chain fatty acids production, especially propionate and butyrate; intestine crypt depth, and the lowest cecal pH. AbsCa% and AbsPi% increased in this order: YE> YR> C (p <0.05). Ca and Pi content in femur, bone density and mineral content, and biomechanical parameters were similar in YE and C, while YR showed the significantly lowest value (p < 0.05). Conclusions: YE increased mineral Abs reaching the retention and bone quality of C. Although YR increased Abs, bone retention and quality did not achieve C values. Seemingly, YE compensated for the negative effect of the higher Pi supply and would be a good strategy to achieve adequate peak bone mass and bone quality, especially in lactose intolerant individuals. (AU)

Tracing PRX1+ cells during molar formation and periodontal ligament reconstruction / 国际口腔科学杂志·英文版

Neural crest-derived mesenchymal stem cells (MSCs) are known to play an essential function during tooth and skeletal development. PRX1+ cells constitute an important MSC subtype that is implicated in osteogenesis. However, their potential function in tooth development and regeneration remains elusive. In the present study, we first assessed the cell fate of PRX1+ cells during molar development and periodontal ligament (PDL) formation in mice. Furthermore, single-cell RNA sequencing analysis was performed to study the distribution of PRX1+ cells in PDL cells. The behavior of PRX1+ cells during PDL reconstruction was investigated using an allogeneic transplanted tooth model. Although PRX1+ cells are spatial specific and can differentiate into almost all types of mesenchymal cells in first molars, their distribution in third molars is highly limited. The PDL formation is associated with a high number of PRX1+ cells; during transplanted teeth PDL reconstruction, PRX1+ cells from the recipient alveolar bone participate in angiogenesis as pericytes. Overall, PRX1+ cells are a key subtype of dental MSCs involved in the formation of mouse molar and PDL and participate in angiogenesis as pericytes during PDL reconstruction after tooth transplantation.

Immunomodulatory effects and mechanisms of distraction osteogenesis / 国际口腔科学杂志·英文版

Distraction osteogenesis (DO) is widely used for bone tissue engineering technology. Immune regulations play important roles in the process of DO like other bone regeneration mechanisms. Compared with others, the immune regulation processes of DO have their distinct features. In this review, we summarized the immune-related events including changes in and effects of immune cells, immune-related cytokines, and signaling pathways at different periods in the process of DO. We aim to elucidated our understanding and unknowns about the immunomodulatory role of DO. The goal of this is to use the known knowledge to further modify existing methods of DO, and to develop novel DO strategies in our unknown areas through more detailed studies of the work we have done.

Rol de los fitoestrógenos en la calcificación vascular e interacciones óseo-vasculares / Role of phytoestrogens in vascular calcification and bonevascular interactions

La osteoporosis y las enfermedades cardiovasculares son patologías prevalentes en mujeres posmenopáusicas. La calcificación vascular es un proceso en el que se produce una distorsión de la arquitectura natural del tejido arterial con una transformación símil osteogénica. La fisiología vascular y la osteogénesis (formación y remodelación ósea) comparten una complejidad metabólica y funcional crítica, que ha sido poco explorada en forma conjunta, lo que ha impulsado la concepción del Eje Óseo-Vascular como nueva área de investigación, con una visión de estudio integradora con la finalidad de identificar vínculos entre ambos sistemas. En virtud de la controversia planteada sobre los riesgos/beneficios de la terapia de reemplazo hormonal para prevenir enfermedades asociadas a la menopausia, se ha incentivado la búsqueda de nuevas opciones de tratamiento. Los fitoestrógenos, como compuestos nutracéuticos, surgen como una potencial alternativa terapéutica. En particular, las isoflavonas presentan gran analogía estructural con el estrógeno humano 17ß-estradiol, lo que les permite unirse al receptor de estrógenos e inducir acciones estrogénicas tanto en células animales como humanas. Basado en la experiencia propia como en lo reportado en la bibliografía, este artículo analiza la información disponible sobre las acciones vasculares y óseas de los fitoestrógenos (específicamente la isoflavona genisteína), con una visión de ciencia traslacional. Es de esperar que los avances en el conocimiento derivado de la ciencia básica, en un futuro cercano, pueda contribuir a decisiones clínicas a favor de promover terapias naturales de potencial acción dual, para la prevención de enfermedades de alta prevalencia y significativo costo social y económico para la población. (AU)

Osteoporosis and cardiovascular diseases are prevalent diseases in postmenopausal women. Vascular calcification is a cellmediated process that leads to the loss of the natural architecture of the arterial vessels due to osteogenic transdifferentiation of smooth muscle cells, and matrix mineralization. Vascular physiology and osteogenesis (bone formation and remodeling) share a critical metabolic and functional complexity. Given the emerging integrative nature of the bonevascular axis, links between both systems are a matter of ongoing interest. In view of the controversy stated about the risks/benefits of hormone replacement therapy to prevent diseases associated with menopause, phytoestrogens arise as a potential natural therapeutic alternative. In particular, isoflavones have a strong structural analogy with the human estrogen 17ß-estradiol, that allows them to bind to the estrogen receptor and induce estrogenic actions in animal and human cells. Based in on our own experience and the information available in the literature, in this paper we provide an overview of the role of phytoestrogens on vascular and bone tissues, with focus on Genistein actions. We wish that the basic knowledge acquired may contribute to guide clinical decisions for the promotion of natural therapies for the treatment of diseases that conspire against human health. (AU)

Osteossíntese femoral associada ao biovidro 60S em tamanduá-bandeira: relato de caso / Femoral osteosynthesis associated with 60s bioglass in tamanduá bandeira: case report

Atropelamentos de animais silvestres são frequentes e muitas vezes causam fraturas ósseas que, se não tratadas adequadamente, levam à morte do animal por complicações ou por inabilidade de sobrevivência no seu habitat natural. O objetivo do presente trabalho foi relatar o uso de placa associada ao pino intramedular e ao biovidro 60S (BV60S) para o tratamento de fratura de fêmur em tamanduá-bandeira. O animal foi resgatado pela polícia ambiental com suspeita de atropelamento. Foi sedado para avaliação clínica e radiográfica, que revelou fratura em fêmur direito. Utilizou-se dexmedetomidina como medicação pré-anestésica, midazolam e cetamina para indução, e isoflurano para manutenção. Também foi realizado bloqueio peridural com bupivacaína e morfina. A osteossíntese foi feita com placa bloqueada 2,7 e pino intramedular 2,5. Colocaram-se 4g de BV60S no foco de fratura para favorecer a osteogênese. O paciente teve recuperação funcional imediata do membro acometido. A reparação óssea ocorreu por segunda intenção, observando-se ossificação completa do calo com consolidação clínica, aos 30 dias, e remodelação quase completa, aos 180 dias. Conclui-se que o uso de placa e pino associado ao BV60S é eficiente no tratamento de fratura de fêmur em tamanduá, permitindo a rápida recuperação e a reintrodução do animal na natureza.(AU)

Roadblocks of wild animals are frequent and often cause bone fractures that if not properly treated lead to the death of the animal due to complications or inability to survive in its natural habitat. The objective of the present study was to report the use of plate rod and bioglass 60S (BG60S) for the treatment of femoral fracture in anteater. The animal was rescued by environmental police on suspicion of being hit. It was sedated for clinical and radiographic evaluation, which revealed a fracture in the right femur. Dexmedetomidine was used as preanesthetic medication, midazolam and ketamine for induction, and isoflurane for maintenance. Epidural blockade with bupivacaine and morphine was also performed. Osteosynthesis was done with a locking plate 2.7 and 2.5 intramedullary pin. 4G of BG60S was placed in the focus of fracture to favor osteogenesis. The patient had immediate functional recovery of the affected limb. The bone repair occurred by second intention, with complete ossification of the callus with clinical consolidation at 30 days, and near complete remodeling at 180 days. It is concluded that the use of plate rod to the BG60S is efficient in the treatment of femur fracture in anteater, allowing the rapid recovery and reintroduction of the animal in the wild.(AU)

Biocerámicos: aspectos farmaco-tecnológicos y clínicos de uso odontológico / Bioceramics: pharmatechnological and clinical aspects of dental use

Se analizan aspectos fármaco-tecnológicos y clínicos de biocerámicos bioabsorbibles compuestos por biovidrios con capacidad osteogénica y microbicida, para ser utilizados como relleno bioactivo en el conducto radicular y como tratamiento terapéutico en el sitio de a lesión apicoperirradicular de origen endodóntico. Mediante un diagrama ternario se consideraron las diversas variables cuyos valores determinan las diferentes fases de los vidrios bioactivos, hasta alcanzar la formación de hidroxiapatita, cuando se someten a un medio biológico. Se analizaron composición y mecanismo de acción en la reparación posendodóntica, que parte de la integración del biomaterial al tejido duro sano, sin formación de fibrosis o proceso inflamatorio inmune (AU)

Pharmacotechnological and clinical aspects of bioabsorbable bioceramics composed of bioglasses with osteogenic and microbicidal capacity are analyzed, to be used as a bioactive filler in the root canal and as a therapeutic treatment at the site of an apicoperiradicular lesion of endodontic origin. By means of a ternary diagram, the various variables whose values determine the different phases of the bioactive glasses were considered, until reaching the formation of hydroxyapatite, when subjected to a biological medium. Composition and mechanism of action were analyzed in post-endodontic repair, which starts from the integration of the biomaterial into healthy hard tissue, without the formation of fibrosis or an immune inflammatory process (AU)

The effects of intro-oral parathyroid hormone on the healing of tooth extraction socket: an experimental study on hyperglycemic rats

Abstract Objective To investigate the effects of intro-oral injection of parathyroid hormone (PTH) on tooth extraction wound healing in hyperglycemic rats. Methodology 60 male Sprague-Dawley rats were randomly divided into the normal group (n=30) and DM group (n=30). Type 1 diabetes mellitus (DM) was induced by streptozotocin. After extracting the left first molar of all rats, each group was further divided into 3 subgroups (n=10 per subgroup), receiving the administration of intermittent PTH, continuous PTH and saline (control), respectively. The intermittent-PTH group received intra-oral injection of PTH three times per week for two weeks. A thermosensitive controlled-release hydrogel was synthesized for continuous-PTH administration. The serum chemistry was determined to evaluate the systemic condition. All animals were sacrificed after 14 days. Micro-computed tomography (Micro-CT) and histological analyses were used to evaluate the healing of extraction sockets. Results The level of serum glucose in the DM groups was significantly higher than that in the non-DM groups (p<0.05); the level of serum calcium was similar in all groups (p>0.05). Micro-CT analysis showed that the DM group had a significantly lower alveolar bone trabecular number (Tb.N) and higher trabecular separation (Tb.Sp) than the normal group (p<0.05). The histological analyses showed that no significant difference in the amount of new bone (hard tissue) formation was found between the PTH and non-PTH groups (p>0.05). Conclusions Bone formation in the extraction socket of the type 1 diabetic rats was reduced. PTH did not improve the healing of hard and soft tissues. The different PTH administration regimes (continuous vs. intermittent) had similar effect on tissue healing. These results demonstrated that the metabolic characteristics of the hyperglycemic rats produced a condition that was unable to respond to PTH treatment.

PI3K/Akt Signaling Involved with Osteoinductive Effects of Achatina fulica Mucus

Abstract Mesenchymal stem cells and osteoblasts play important roles in bone formation. Achatina fulica mucus presented the property of osteoinduction. This study aimed to examine the effects of A. fulica mucus on human mesenchymal stem cell (hMSC) and human fetal osteoblastic cell line (HFOB) differentiation. The integrated effects of A. fulica mucus and polycaprolactone (PCL) on the differentiation of hMSCs were tested. The cell viability of hMSCs treated with A. fulica mucus was investigated by the MTT assay. The cell mineralization was observed by Alizarin Red S staining, the gene expression was investigated using RT-PCR, and the PI3K activation was studied using flow cytometry. The results indicated that A. fulica mucus induced osteogenic differentiation in hMSCs and HFOBs by upregulation of the osteogenic markers; osteopontin (OPN) and osteocalcin (OCN). The results of the Alizarin Red S staining indicated that A. fulica mucus supported mineralization in both hMSCs and HFOBs. The hMSCs cultured on PCL supplemented with A. fulica mucus showed significantly increased RUNX2 and OPN expressions. A. fulica mucus was observed to increase PI3K activation in hMSCs. The findings of this study suggested that A. fulica mucus and biomaterials could be applied together for use in bone regeneration in the future.

Evaluación de la Administración Infiltrativa de vitamina E y alendronato en la Reparación de Alvéolos Post Exodoncia de Ratas / Evaluation of the Infiltrative Administration of Vitamin E and Alendronate in the Repair of Alveoli Post-Extraction in Rats

RESUMEN: Los bisfosfonatos (BP) disminuyen la resorción ósea al frenar la actividad de los osteoclastos. La vitamina E es antioxidante y su efecto positivo en el hueso sería mediante la prevención del estrés oxidativo. Se estudió la administración infiltrativa de Alendronato y Vitamina E para determinar si favorecían la formación de hueso en la reparación ósea del alvéolo postexodoncia. Se utilizaron ratas machos Wistar (n=96), de 90 ± 15 g, se les realizó la exodoncia de los primeros molares inferiores. Fueron dividos en 4 grupos: Un grupo control (C) recibió solución salina. El grupo AL 0,5 mg/ Kg; grupo E recibió 20 mg/kg; y grupo con tratamiento combinado AL y E. Los animales se sacrificaron a los 0, 7, 15 y 30 días postextracción. Se realizó la resección de las mandíbulas; las muestras fueron descalcificadas con EDTA y luego se incluyeron en parafina. Se realizaron cortes histológicos y se colorearon con Hematoxilina/Eosina. Se realizó análisis histológico e histomorfométrico. Se utilizó análisis de Varianza (ANOVA). En el análisis histológico, a los 7 y 15 días el grupo E presentó mayor neoformación de tejido óseo que los otros grupos. A los 30 días se observó hueso maduro con presencia de osteonas en el grupo E. En el estudio histomorfométrico a los 15 y 30 días se evidencian diferencias significativas en el número de osteoblastos por mm lineal, entre el grupo AL + E y C (p<0,01) y a los 30 días se encontró diferencia entre el grupo E y C (p<0,01). Al medir espesor trabecular se observó a los 30 días diferencias significativas entre el grupo AL+E y C (p<0,01) y entre el grupo C y E (p<0,01). La Vitamina E demostró que administrada por vía infiltrativa favorece la remodelación ósea en los alvéolos post exodoncia.

ABSTRACT: Bisphosphonates (BP) decrease bone resorption to curb the activity of the osteoclasts. Vitamin E is an antioxidant and its positive effect on the bone would be by preventing oxidative stress. Infiltrative Alendronate and vitamin E administration wasstudied to determine if they favored the formation of bone in bone repair of the postextraction alveolus. Male Wistar rats were used (n = 96), 90 ± 15 g, underwent extraction of the lower first molars. They were divided into 4 groups: A control group (C) received saline. The Group at the 0.5 mg/Kg; Group E received 20 mg/kg; and combined treatment group to AL and E. The animals were sacrificed at days 0, 7, 15 and 30 post extraction. With the resection of the jaws; samples were decalcified with EDTA and then included in paraffin. Histological cuts were made and colored with Hematoxylin/ eosin. Histomorphometric and histological analysis was performed. We used analysis of variance (ANOVA). In the histological analysis, 7 to 15 days the Group E presented greater neoformation of bone tissue than other groups. At 30 days mature bone was observed, with presence of osteons in the Group E. Study shows significant differences in the number of osteoblast histomorphometric function to 15 to 30 days by linear mm, among the group to the + E and C (p < 0.01) and 30-day difference was found among the Group E and C (p < 0.01). When measuring thick trabecular, significant differences were observed at 30 days between the AL+E and C Group (p < 0.01) and between C and E (p < 0.01). Vitamin E showed that administered infiltrative favors the bone remodeling in post extraction sockets.

One-year adolescent bone mineral density and bone formation marker changes through the use or lack of use of combined hormonal contraceptives / Alterações na densidade mineral óssea e nos marcadores de formação óssea em adolescentes usuárias ou não de contraceptivos hormonais orais combinados por período de um ano

Abstract Objective: The objective of this study was to evaluate the effects of two low-dose combined oral contraceptives on bone metabolism in adolescents for one year. Methods: This was a quasi-experimental study. The adolescents were divided into three groups: oral contraceptives 1 (n = 42) (20 µg EE/150 µg desogestrel), oral contraceptives 2 (n = 66) (30 µg EE/3 mg drospirenone), and a control group (n = 70). Adolescents underwent anthropometric assessment and densitometry (dual-energy X-ray). Bone age and bone formation markers (osteocalcin and bone alkaline phosphatase) were evaluated. The oral contraceptives users were evaluated again after 12 months. Linear regression analysis was used to indirectly study the effect of each additional year of chronological age on anthropometric and densitometric variables as well as on bone markers in the control group. Results: At study entry, no significant differences were observed between the oral contraceptives 1, oral contraceptives 2, and controls in the analyzed variables. Linear regression analysis showed an increase in bone mineral density and bone mineral content for each additional year. There was a significant reduction in bone alkaline phosphatase levels; no significant difference was observed for osteocalcin in control individuals. Comparison of dual-energy X-ray variables at baseline and after one year showed no significant differences in the oral contraceptives 1 or oral contraceptives 2 groups. A significant reduction in bone alkaline phosphatase and osteocalcin levels was observed in both the oral contraceptives 1 and oral contraceptives 2 groups. Conclusion: Adolescent women gain peak bone mass during this phase of life. Two low-dose combined oral hormonal contraceptives were associated with lower bone gain and lower bone formation markers than in untreated controls.

Resumo: Objetivo: O objetivo deste estudo foi avaliar os efeitos de dois contraceptivos orais combinados de baixa dosagem por um ano sobre o metabolismo ósseo em adolescentes. Métodos: Este foi um estudo quase experimental. As adolescentes foram divididas em três grupos: contraceptivos orais 1 (n = 42) (20 µg de EE/150 µg de desogestrel), contraceptivos orais 2 (n = 66) (30 µg EE/3 mg de drospirenona) e grupo controle (n = 70). As adolescentes foram submetidas à avaliação antropométrica e densitometria (raio-X de dupla energia). Foram avaliados a idade óssea e os marcadores de formação óssea (osteocalcina e fosfatase alcalina óssea). As usuárias de contraceptivos orais foram novamente avaliadas após 12 meses. A análise de regressão linear foi utilizada para estudar, indiretamente, o efeito de cada ano adicional da idade cronológica sobre as variáveis antropométricas e densitométricas e sobre os marcadores ósseos no grupo de controle. Resultados: No início do estudo, não foram observadas diferenças significativas nas variáveis analisadas entre as usuárias de contraceptivos orais 1, contraceptivos orais 2 e o grupo controle. A análise de regressão linear mostrou um aumento na densidade mineral óssea e no conteúdo mineral ósseo para cada ano adicional. Houve uma redução significativa nos níveis de fosfatase alcalina óssea e não foi observada diferença significativa para osteocalcina nos indivíduos controles. A comparação das variáveis do raio-X de dupla energia no início e após um ano não mostrou diferença significativa no grupo de contraceptivos orais 1 ou contraceptivos orais 2. Foi observada uma redução significativa nos níveis de fosfatase alcalina óssea e osteocalcina nos dois grupos contraceptivos orais 1 e contraceptivos orais 2. Conclusão: As adolescentes atingiram o pico de massa óssea durante essa fase da vida. Duas formulações de contraceptivos hormonais orais de baixa dosagem, após um ano de uso, se associaram a menor incremento na densidade mineral óssea e menor concentração de marcadores de formação óssea quando confrontados com resultados de adolescentes não usuárias de contraceptivos.

The influence of Aloe vera with mesenchymal stem cells from dental pulp on bone regeneration: characterization and treatment of non-critical defects of the tibia in rats

Abstract Objective This study aimed to evaluate the inflammatory effect and bone formation in sterile surgical failures after implantation of a collagen sponge with mesenchymal stem cells from human dental pulp (hDPSCs) and Aloe vera. Material and Methods Rattus norvegicus (n=75) were divided into five experimental groups according to treatment: G1) control (blood clot); G2) Hemospon®; G3) Hemospon® in a culture medium enriched with 8% Aloe vera; G4) Hemospon® in a culture medium containing hDPSCs and G5) Hemospon® in a culture medium enriched with 8% Aloe vera and hDPSCs. On days 7, 15 and 30, the animals were euthanized, and the tibia was dissected for histological, immunohistochemistry and immunofluorescence analyses. The results were analyzed using nonparametric Kruskal-Wallis test and Dunn's post-test. Results On days 7 and 15, the groups with Aloe vera had less average acute inflammatory infiltrate compared to the control group and the group with Hemospon® (p<0.05). No statistically significant difference was found between the groups regarding bone formation at the three experimental points in time. Osteopontin expression corroborated the intensity of bone formation. Fluorescence microscopy revealed positive labeling with Q-Tracker® in hDPSCs before transplantation and tissue repair. Conclusion The results suggest that the combination of Hemospon®, Aloe vera and hDPSCs is a form of clinical treatment for the repair of non-critical bone defects that reduces the inflammatory cascade's effects.

Periapical bone response to bacterial lipopolysaccharide is shifted upon cyclooxygenase blockage

Abstract Objectives: Infection, inflammation and bone resorption are closely related events in apical periodontitis development. Therefore, we sought to investigate the role of cyclooxygenase (COX) in osteoclastogenesis and bone metabolism signaling in periapical bone tissue after bacterial lipopolysaccharide (LPS) inoculation into root canals. Methodology: Seventy two C57BL/6 mice had the root canals of the first molars inoculated with a solution containing LPS from E. coli (1.0 mg/mL) and received selective (celecoxib) or non-selective (indomethacin) COX-2 inhibitor. After 7, 14, 21 and 28 days the animals were euthanized and the tissues removed for total RNA extraction. Evaluation of gene expression was performed by qRT-PCR. Statistical analysis was performed using analysis of variance (ANOVA) followed by post-tests (α=0.05). Results: LPS induced expression of mRNA for COX-2 (Ptgs2) and PGE2 receptors (Ptger1, Ptger3 and Ptger4), indicating that cyclooxygenase is involved in periapical response to LPS. A signaling that favours bone resorption was observed because Tnfsf11 (RANKL), Vegfa, Ctsk, Mmp9, Cd36, Icam, Vcam1, Nfkb1 and Sox9 were upregulated in response to LPS. Indomethacin and celecoxib differentially modulated expression of osteoclastogenic and other bone metabolism genes: celecoxib downregulated Igf1r, Ctsk, Mmp9, Cd36, Icam1, Nfkb1, Smad3, Sox9, Csf3, Vcam1 and Itga3 whereas indomethacin inhibited Tgfbr1, Igf1r, Ctsk, Mmp9, Sox9, Cd36 and Icam1. Conclusions: We demonstrated that gene expression for COX-2 and PGE2 receptors was upregulated after LPS inoculation into the root canals. Additionally, early administration of indomethacin and celecoxib (NSAIDs) inhibited osteoclastogenic signaling. The relevance of the cyclooxygenase pathway in apical periodontitis was shown by a wide modulation in the expression of genes involved in both bone catabolism and anabolism.

Retinoic acid increases the effect of bone morphogenetic protein type 2 on osteogenic differentiation of human adipose-derived stem cells

Abstract Bone morphogenetic protein type 2 (BMP-2) and retinoic acid (RA) are osteoinductive factors that stimulate endogenous mechanisms of bone repair which can be applied on management of osseous defects in oral and maxillofacial fields. Objective Considering the different results of RA on osteogenesis and its possible use to substitute/potency BMP-2 effects, this study evaluated the outcomes of BMP-2, RA, and BMP-2+RA treatments on in vitro osteogenic differentiation of human adipose-derived stem cells (ASCs) and the signaling pathway(s) involved. Material and Methods ASCs were treated every other day with basic osteogenic medium (OM) alone or supplemented with BMP-2, RA, or BMP-2+RA. Alkaline phosphatase (ALP) activity was determined using the r-nitrophenol method. Extracellular matrix mineralization was evaluated using von Kossa staining and calcium quantification. Expression of osteonectin and osteocalcin mRNA were determined using qPCR. Smad1, Smad4, phosphorylated Smad1/5/8, BMP-4, and BMP-7 proteins expressions were analyzed using western blotting. Signaling pathway was evaluated using the IPA® software. Results RA promoted the highest ALP activity at days 7, 14, 21, and 28, in comparison to BMP-2 and BMP-2+RA. BMP-2+RA best stimulated phosphorylated Smad1/5/8 protein expression at day 7 and Smad4 expression at days 7, 14, 21, and 28. Osteocalcin and osteonectin mRNA expressions were best stimulated by BMP-2+RA at day 7. Matrix mineralization was most improved by BMP-2+RA at days 12 and 32. Additionally, BMP-2+RA promoted the highest BMP signaling pathway activation at days 7 and 14, and demonstrated more activation of differentiation of bone-forming cells than OM alone. Conclusions In summary, RA increased the effect of BMP-2 on osteogenic differentiation of human ASCs.

Quantification of pro-inflammatory cytokines and osteoclastogenesis markers in successful and failed orthodontic mini-implants

Abstract Objectives: Miniscrew has been frequently used, considering that anchorage control is a critical point in orthodontic treatment, and its failure, the main adverse problem. Using two groups of stable (successful) and unstable (failed) mini-implants, this in vivo study aimed to quantify proinflammatory cytokines IL-1 α, IL-6, IL-17, and TNF-α and osteoclastogenesis marker RANK, RANKL, and OPG in gingival tissue, using the real-time polymerase chain reaction technique. Methodology: Thirteen patients of both sexes (11-49 years old) under orthodontic treatment were selected, obtaining 11 successful and 7 failed mini-implants. The mini-implants were placed and removed by the same surgeon, in both jaws. The mean time of permanence in the mouth was 29.4 months for successful and 7.6 months for failed mini-implants. At removal time, peri-mini-implant gingival tissue samples were collected and processed for quantification of the proinflammatory cytokines and osteoclastogenesis markers. Nonparametric Wilcoxon rank-sum test considering the clusters and Kruskal-Wallis test were used for statistical analysis (α=0.05). Results: No significant difference (p>0.05) was observed between the groups for either quantification of cytokines or osteoclastogenesis markers, except for IL-6 (p<0.05). Conclusions: It may be concluded that the expression of IL-1α, IL-17, TNF-α, RANK, RANKL, and OPG in peri-implant gingival tissue were not determinant for mini-implant stability loss, but the higher IL-6 expression could be associated with mini-implant failure.

Action of a deproteinized xenogenic biomaterial in the process of bone repair in rats submitted to inhalation of cigarette smoke

Abstract Purpose: To investigate if the inorganic bovine bone matrix changes the bone formation in rats submitted to inhalation of cigarette smoke. Methods: Twenty Wistar rats were divided into two groups: Cigarette Clot Group (CCG), which in the inhalation chamber received the smoke of 10 cigarettes, 3 times a day, 10 minutes, for 30 days and had the surgical cavity filled by clot; Cigarette Biomaterial Group (CBG), submitted to the same inhalation technique but with the cavity filled by biomaterial. Results: In CCG there was a significant difference of new bone tissue in the analyzed periods (15 and 45 days), and in 15 days, there was 4.8 ± 0.42 of bone formed and 11.73 ± 0.59 (p <0.05) in 45 days. The CBG also showed a significant difference between the periods of 15 to 45 days, being respectively 6.16 ± 0.30 and 11.60 ± 0.61. However, when the groups were compared, within the same analyzed periods, a significant difference was observed only in the period of 15 days, with the new bone percentage being greater in the CBG. Conclusion: The bone matrix acted as an osteoinductive biomaterial, biocompatible and aided in the repair process, mainly in the initial period of recovery.

Demineralized bone matrix and calcium-phosphate cement in bone regeneration in rats

Abstract Purpose: To compare bone regeneration in critical-sized defects in rat calvarium using demineralized bone matrix and calcium phosphate cement. Methods: Thirty Wistar rats were divided into 3 groups of 10 animals each. Two defects of 5-mm were made in the parietal bones of each animal. Group I had calcium phosphate cement placed in the experimental defect, Group II had filled with demineralized bone matrix and Group III had with the combination of the matrix and cement in equal parts. All animals had one defect left unfilled to serve as controls. Five animals in each group were sacrificed at 4 and 8 weeks. Histomorphometric analysis was used to quantify the amount of new bone within the defects. Results: The results showed that demineralized bone matrix-treated defects had significantly more new bone at 4 weeks compared to calcium phosphate cement-treated defects (p=0.03) and also had significantly more new bone at 8 weeks compared to unfilled defects (p=0.04). Conclusions: The demineralized bone matrix was superior to calcium phosphate cement in bone regeneration. It seems that calcium phosphate cement acted by inhibiting the osteogenesis when associated with a demineralized bone matrix and this combination should not be recommended.

Hyaluronic acid accelerates bone repair in human dental sockets: a randomized triple-blind clinical trial

Abstract This study evaluated the effects of hyaluronic acid (HA) on bone repair of human dental sockets. Thirty-two lower first premolars were extracted from 16 patients (2 per patient) for orthodontic reasons. Following the extractions, one socket was randomly filled with 1% HA gel, while the other was allowed to naturally fill with blood clot. After 30 and 90 days of surgery, patients underwent cone beam computed tomography. Five central orthoradial slices were captured from each socket. The gray intensity was measured in each image and results were reported as mean percentage of bone formation. The buccolingual alveolar ridge width was measured and dimensional changes were compared between the postoperative intervals. The pattern of alveolar trabecular bone was evaluated through the fractal dimension. Treated sockets showed a higher percentage of bone formation and fractal dimension values (58.17% and 1.098, respectively) compared with controls (48.97% and 1.074, respectively) in the 30-day postoperative period (p < 0.05). After 90 days, there was no significant difference between groups. Additionally, no significant difference was found between groups regarding the alveolar dimensions (p > 0.05). Use of 1% HA gel after tooth extraction accelerates bone repair in human dental sockets.

Comparing osteogenic effects between concentrated growth factors and the acellular dermal matrix

Abstract Concentrated growth factor (CGF) is an autogenuous product that contains highly concentrated number of platelets and can be derived from venous blood by selective centrifugation. It has been speculated that local growth factors in human platelets (insulinlike growth factor, IGF; transforming growth factor, TGF-b; platelet derived growth factor, PDGF) would enhance healing of grafts and also counteract resorption. The osteogensis effect of CGF and acellular dermal matrix (ADM) for alveolar cleft defects was evaluated in this study. Twenty alveolar cleft patients were divided randomly into two groups. One group underwent guided bone regeneration (GBR) using acellular dermal matrix film combined with alveolar bone grafting using iliac crest bone grafts (GBR group), while the other group underwent alveolar bone grafting combined with CGF (CGF group). Cone beam computed tomography (CBCT) images were obtained at 1 week and 6 months following the procedure. Using Mimics 17.0 software, the bone resorption rate and bone density improvement rate were calculated and compared between the two groups. Although not significant between ADM and CGF in bone resorption rate, the bone density improvement in cases with CGF(61.62 ± 4.728%) was much better than in cases with ADM (27.05 ± 5.607%) (p = 0.0002). Thus, CGF could be recommended to patients with alveolar cleft as a better choice.