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1.
Braz Oral Res ; 38: e021, 2024.
Artículo en Inglés | MEDLINE | ID: mdl-38477807

RESUMEN

The present study aimed to evaluate the influence of titanium surface nanotopography on the initial bacterial adhesion process by in vivo and in vitro study models. Titanium disks were produced and characterized according to their surface topography: machined (Ti-M), microtopography (Ti-Micro), and nanotopography (Ti-Nano). For the in vivo study, 18 subjects wore oral acrylic splints containing 2 disks from each group for 24 h (n = 36). After this period, the disks were removed from the splints and evaluated by microbial culture method, scanning electron microscopy (SEM), and qPCR for quantification of Streptococcus oralis, Actinomyces naeslundii, Fusobacterium nucleatum, as well as total bacteria. For the in vitro study, adhesion tests were performed with the species S. oralis and A. naeslundii for 24 h. Data were compared by ANOVA, with Tukey's post-test. Regarding the in vivo study, both the total aerobic and total anaerobic bacteria counts were similar among groups (p > 0.05). In qPCR, there was no difference among groups of bacteria adhered to the disks (p > 0.05), except for A. naeslundii, which was found in lower proportions in the Ti-Nano group (p < 0.05). In the SEM analysis, the groups had a similar bacterial distribution, with a predominance of cocci and few bacilli. In the in vitro study, there was no difference in the adhesion profile for S. oralis and A. naeslundii after 24 h of biofilm formation (p > 0.05). Thus, we conclude that micro- and nanotopography do not affect bacterial adhesion, considering an initial period of biofilm formation.


Asunto(s)
Adhesión Bacteriana , Titanio , Humanos , Fusobacterium nucleatum , Microscopía Electrónica de Rastreo , Proyectos de Investigación
2.
Braz Dent J ; 33(3): 82-91, 2022.
Artículo en Inglés | MEDLINE | ID: mdl-35766721

RESUMEN

The aim of this study was to evaluate a Demineralized Human Dentine Matrix (DHDM) as viable biomaterial for alveolar ridge preservation in a rat model. Wistar rats were submitted to the extraction of maxillary first molars bilaterally. Sockets were filled with biomaterials and divided into 4 experimental groups (n=5): blood clot, autogenous bone, bovine-derived xenograft (BDX) and DHDM. Animals were sacrificed at 7, 14 e 28 days. Microtomography (uCT) volumetric evaluation and qualitative histological analyses were performed. Results obtained through the uCT showed similar values between the DHDM and the other experimental groups. The histological evaluation demonstrated DHDM with an unspecific inflammatory process and bone neoformation with slow reabsorption of the material. This result indicates that DHDM implanted in rat sockets is biocompatible and reduces the alveolar ridge volume loss after tooth extraction.


Asunto(s)
Pérdida de Hueso Alveolar , Alveolo Dental , Proceso Alveolar , Animales , Bovinos , Dentina , Humanos , Ratas , Ratas Wistar , Extracción Dental , Alveolo Dental/cirugía
3.
Lasers Med Sci ; 26(4): 539-43, 2011 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-21387157

RESUMEN

The present in vitro study evaluated parameters of osteogenesis under the influence of low-level laser therapy (LLLT) at different doses. Osteogenic cells originated from rat calvaria were cultivated in polystyrene plates and exposed to a laser irradiation using an indium-gallium-aluminum phosphide therapeutic laser (InGaAIP), at wavelength of 685 nm, power of 35 mW, 600-µm-diameter optical fiber, and continuous wave. In the attempt of observing the existence of a dose response and its effects, laser irradiation was performed at 25, 77, and 130 J/cm(2) (7, 22, and 37 s, respectively). The following parameters were assessed: growth curve (4, 7, and 11 days), cell viability (24 h), and nodular formation of mineralized matrix (14 days). The results did not show significant differences related to the growth curve (4, 7, and 11 days) and cell viability (24 h). Within 14 days, osteogenic cultures showed nodular areas with well-defined calcified matrix. The total area stained with Alizarin Red did not show any differences between doses of 25 and 130 J/cm(2). However, the percentage of stained area was significantly higher in the 25 J/cm(2) group when compared to the group of 77 J/cm(2) (Kruskal-Wallis test, p < 0.05). It was possible to conclude that the 685-nm laser irradiation (at 25, 77, and 130 J/cm(2)) did not influence cell growth and proliferation, although the extracellular mineralization process may have its pattern altered by the LLLT on osteogenic cell cultures.


Asunto(s)
Terapia por Luz de Baja Intensidad/métodos , Osteoblastos/efectos de la radiación , Osteogénesis/efectos de la radiación , Animales , Técnicas de Cultivo de Célula , Proliferación Celular/efectos de la radiación , Supervivencia Celular/efectos de la radiación , Relación Dosis-Respuesta en la Radiación , Terapia por Luz de Baja Intensidad/instrumentación , Osteoblastos/fisiología , Ratas , Estadísticas no Paramétricas
4.
Braz. oral res. (Online) ; 38: e021, 2024. tab, graf
Artículo en Inglés | LILACS-Express | LILACS, BBO | ID: biblio-1550156

RESUMEN

Abstract The present study aimed to evaluate the influence of titanium surface nanotopography on the initial bacterial adhesion process by in vivo and in vitro study models. Titanium disks were produced and characterized according to their surface topography: machined (Ti-M), microtopography (Ti-Micro), and nanotopography (Ti-Nano). For the in vivo study, 18 subjects wore oral acrylic splints containing 2 disks from each group for 24 h (n = 36). After this period, the disks were removed from the splints and evaluated by microbial culture method, scanning electron microscopy (SEM), and qPCR for quantification of Streptococcus oralis, Actinomyces naeslundii, Fusobacterium nucleatum, as well as total bacteria. For the in vitro study, adhesion tests were performed with the species S. oralis and A. naeslundii for 24 h. Data were compared by ANOVA, with Tukey's post-test. Regarding the in vivo study, both the total aerobic and total anaerobic bacteria counts were similar among groups (p > 0.05). In qPCR, there was no difference among groups of bacteria adhered to the disks (p > 0.05), except for A. naeslundii, which was found in lower proportions in the Ti-Nano group (p < 0.05). In the SEM analysis, the groups had a similar bacterial distribution, with a predominance of cocci and few bacilli. In the in vitro study, there was no difference in the adhesion profile for S. oralis and A. naeslundii after 24 h of biofilm formation (p > 0.05). Thus, we conclude that micro- and nanotopography do not affect bacterial adhesion, considering an initial period of biofilm formation.

5.
Braz. dent. j ; 33(3): 82-91, July-Sept. 2022. graf
Artículo en Inglés | LILACS-Express | LILACS, BBO | ID: biblio-1384027

RESUMEN

Abstract The aim of this study was to evaluate a Demineralized Human Dentine Matrix (DHDM) as viable biomaterial for alveolar ridge preservation in a rat model. Wistar rats were submitted to the extraction of maxillary first molars bilaterally. Sockets were filled with biomaterials and divided into 4 experimental groups (n=5): blood clot, autogenous bone, bovine-derived xenograft (BDX) and DHDM. Animals were sacrificed at 7, 14 e 28 days. Microtomography (uCT) volumetric evaluation and qualitative histological analyses were performed. Results obtained through the uCT showed similar values between the DHDM and the other experimental groups. The histological evaluation demonstrated DHDM with an unspecific inflammatory process and bone neoformation with slow reabsorption of the material. This result indicates that DHDM implanted in rat sockets is biocompatible and reduces the alveolar ridge volume loss after tooth extraction.


Resumo O objetivo deste estudo foi avaliar a Matriz Dentinária Humana Desmineralizada (MDHD) como biomaterial viável para preservação do rebordo alveolar, no modelo em rato. Ratos Wistar foram submetidos à exodontias dos primeiros molares superiores bilateralmente. Os alvéolos foram preenchidos com biomateriais e divididos em 4 grupos experimentais (n=5): coágulo sanguíneo, osso autógeno, osso xenógeno de origem bovina e MDHD. Os animais foram sacrificados aos 7, 14 e 28 dias. Foram realizadas avaliações volumétricas por microtomografia (uCT) e análises histológicas qualitativas. Os resultados obtidos por meio do uCT mostraram valores semelhantes entre o MDHD e os demais grupos experimentais. A avaliação histológica demonstrou MDHD com processo inflamatório inespecífico e neoformação óssea com lenta reabsorção do material. Esse resultado indica que a MDHD implantada em alvéolo de rato é biocompatível e reduz a perda de volume do rebordo alveolar após extração dentária.

6.
J. health sci. (Londrina) ; 23(1): https://revista.pgsskroton.com/index.php/JHealthSci/article/view/8386, 20210330.
Artículo en Inglés | LILACS-Express | LILACS | ID: biblio-1222917

RESUMEN

Gingival smile is a term used to describe an aesthetic condition in which excessive gingival exposure at the jaw level occurs during smile. There are several factors related to its etiology, the most common is the altered passive eruption of anterior superior teeth. To correct this disharmony, a multidisciplinary approach is necessary, and the treatment plan depends on a correct diagnosis and assessment for a better prognosis. The present study aims to describe a clinical case where periodontal surgical techniques were used to correct this condition. Female patient, 25 years old, with aesthetic complaint of the amount of gum exposed when smiling and diagnosed with altered passive eruption. Clinical crown augmentation surgery was performed on the anterior superior teeth. After 1 and 2 years, periodontal clinical parameters (probing bleeding, probing depth, clinical attachment level, crown length, keratinized mucosa width and plaque index) were reassessed, through clinical examination, digital photographic monitoring and measurement tools. In two years, it was possible to note the stability of the results achieved, maintaining values similar to those of the immediate postoperative period. The case report confirmed the success of the clinical crown augmentation surgery and the periodontal parameters stability evaluated after 2 years. (AU)


Sorriso gengival é o termo utilizado para descrever uma condição estética em que ocorre uma exposição gengival excessiva ao nível da maxila, durante o sorriso. Há diversos fatores relacionados a sua etiologia, sendo a mais comum a erupção passiva alterada dos dentes ântero-superiores. Para correção dessa desarmonia é necessária uma abordagem multidisciplinar, sendo o plano de tratamento dependente de um correto diagnóstico e avaliação para um melhor prognóstico. O presente estudo tem objetivo de descrever um caso clínico onde técnicas cirúrgicas periodontais foram utilizadas para correção dessa condição. Paciente gênero feminino, 25 anos de idade, com queixa estética da quantidade de gengiva exposta ao sorrir e com diagnóstico de erupção passiva alterada. Foi submetida a cirurgia de aumento de coroa clínica nos dentes antero-superiores. Após 1 e 2 anos foram reavaliados os parâmetros clínicos periodontais (sangramento a sondagem, profundidade de sondagem, perda de inserção, comprimento da coroa, largura da mucosa queratinizada e índice de placa), através de exame clinico, acompanhamento digital fotográfico e ferramentas de medição de imagem. Em dois anos, foi possível constatar a estabilidade dos resultados alcançados, mantendo valores semelhantes aos do pós-operatório imediato. O relato de caso confirmou o sucesso da cirurgia de aumento de coroa clínica e a estabilidade dos parâmetros periodontais avaliados após 2 anos. (AU)

7.
Dental Press J Orthod ; 21(2): 95-101, 2016.
Artículo en Inglés | MEDLINE | ID: mdl-27275621

RESUMEN

OBJECTIVE: This study evaluated alveolar bone loss around mandibular incisors, induced by the Herbst appliance. METHODS: The sample consisted of 23 patients (11 men, 12 women; mean age of 15.76 ± 1.75 years), Class II, Division 1 malocclusion, treated with the Herbst appliance. CBCT scans were obtained before treatment (T0) and after Herbst treatment (T1). Vertical alveolar bone level and alveolar bone thickness of mandibular incisors were assessed. Buccal (B), lingual (L) and total (T) bone thicknesses were assessed at crestal (1), midroot (2) and apical (3) levels of mandibular incisors. Student's t-test and Wilcoxon t-test were used to compare dependent samples in parametric and nonparametric cases, respectively. Pearson's and Spearman's rank correlation analyses were performed to determine the relationship of changes in alveolar bone thickness. Results were considered at a significance level of 5%. RESULTS: Mandibular incisors showed no statistical significance for vertical alveolar bone level. Alveolar bone thickness of mandibular incisors significantly reduced after treatment at B1, B2, B3, T1 and significantly increased at L2. The magnitude of the statistically significant changes was less than 0.2 mm. The changes in alveolar bone thickness showed no statistical significance with incisor inclination degree. CONCLUSIONS: CBCT scans showed an association between the Herbst appliance and alveolar bone loss on the buccal surface of mandibular incisors; however, without clinical significance.


Asunto(s)
Pérdida de Hueso Alveolar/diagnóstico por imagen , Tomografía Computarizada de Haz Cónico , Maloclusión Clase II de Angle/diagnóstico por imagen , Maloclusión Clase II de Angle/terapia , Diseño de Aparato Ortodóncico , Aparatos Ortodóncicos Funcionales , Adolescente , Brasil , Femenino , Estudios de Seguimiento , Encía/diagnóstico por imagen , Humanos , Incisivo/diagnóstico por imagen , Masculino , Mandíbula/diagnóstico por imagen , Periodoncio/diagnóstico por imagen , Estudios Retrospectivos , Técnicas de Movimiento Dental
8.
J. health sci. (Londrina) ; 23(2): 110-112, 20210621.
Artículo en Inglés | LILACS-Express | LILACS | ID: biblio-1283109

RESUMEN

Among the available techniques for gingival recession treatment, the main surgical technique for gain of keratinized tissue is the free gingival graft. This procedure is also indicated for vestibule extension and frenulum removal. The technique consists of the epithelial and connective tissues removal from a donor site and its repositioning on to a recipient site, being an effective primary stability mandatory for the healing process. The aim of this study was to describe a case report of a 35-year-old male, who reported a postoperative complication in donor area, after a free gingival graft which occurred 07 days later. This situation occurred after patient reported having rinsed his mouth with hot water during shower. Due to that, a 1mm thick acetate tray was readymade for the donor site comfort and protection. Among the demands presented in this case, free gingival graft was the primary surgical choice to increase keratinized tissue. Despite the patient's morbidity, due to the two surgical sites, the use of the acetate tray showed great reduction in patient's discomfort and trauma. This approach proved to be successful since the patient described increase in self-esteem and oral hygiene facilitation which in combination contributed to satisfactory final results. (AU)


Entre as técnicas disponíveis para o tratamento da recessão gengival, a principal técnica cirúrgica para ganho de tecido queratinizado é o enxerto gengival livre. Este procedimento também é indicado para extensão do vestíbulo e remoção do frênulo. A técnica consiste na remoção de tecidos epiteliais e conectivos de um local doador e seu reposicionamento no local receptor, sendo necessária uma estabilidade primária eficaz para o processo de cicatrização. O objetivo deste estudo foi descrever um relato de caso de um homem de 35 anos, que relatou uma complicação pós-operatória na área doadora, 07 dias após a realização de um enxerto gengival livre. Essa situação ocorreu depois que o paciente relatou ter enxaguado a boca com água quente durante o banho. Devido a isso, uma placa de acetato de 1 mm de espessura foi preparada para conforto e proteção do local doador. Entre as demandas apresentadas neste caso, o enxerto gengival livre foi a principal opção cirúrgica para aumentar o tecido queratinizado. Apesar da morbidade do paciente, devido aos dois locais cirúrgicos, o uso da placa de acetato demonstrou grande redução no desconforto e trauma do paciente. Essa abordagem mostrou-se bem-sucedida, uma vez que o paciente descreveu aumento da autoestima e facilitação da higiene bucal, o que em conjunto contribuiu para resultados finais satisfatórios. (AU)

9.
J Appl Oral Sci ; 23(5): 479-85, 2015 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-26537718

RESUMEN

OBJECTIVE: This study evaluated the frequency of root resorption during the orthodontic treatment with Herbst appliance by Cone Beam Computed Tomography (CBCT). MATERIAL AND METHODS: The sample comprised 23 patients (11 men, 12 women; mean ages 15.76±1.75 years) with Class II division 1 malocclusion, treated with Herbst appliance. CBCT was obtained before treatment (T0) and after Herbst treatment (T1). All the dental roots, except third molars, were evaluated, and apical root resorption was determined using the axial guided navigation method. Paired t-tests and Wilcoxon T Test were used to compare the dependent samples in parametric and nonparametric cases, respectively. Chi-Square Test with Yates' correction was used to evaluate the relationship between apical root resorption and gender. Results were considered at a significance level of 5%. RESULTS: Apical resorption was detected by CBCT in 57.96% of 980 roots that underwent Herbst appliance treatment. All patients had minimal resorption and there was no statistical significance between the genders. CONCLUSION: CBCT three-dimensional evaluation showed association between Herbst appliance and minimal apical root resorption, mostly in the anchoring teeth, without clinical significance.


Asunto(s)
Tomografía Computarizada de Haz Cónico/métodos , Aparatos Ortodóncicos Funcionales/efectos adversos , Resorción Radicular/diagnóstico por imagen , Ápice del Diente/diagnóstico por imagen , Adolescente , Femenino , Humanos , Imagenología Tridimensional , Masculino , Variaciones Dependientes del Observador , Odontometría , Interpretación de Imagen Radiográfica Asistida por Computador , Estudios Retrospectivos , Resorción Radicular/etiología , Factores Sexuales , Estadísticas no Paramétricas , Técnicas de Movimiento Dental/efectos adversos
10.
PLoS One ; 10(5): e0128098, 2015.
Artículo en Inglés | MEDLINE | ID: mdl-26020797

RESUMEN

Statins are important lipid-lowering agents with other pleiotropic effects. Several studies have explored a possible protective effect of statins to reduce the morbidity and mortality of many infectious diseases. Staphylococcus aureus is one of the main pathogens implicated in nosocomial infections; its ability to form biofilms makes treatment difficult. The present study observed the MIC of atorvastatin, pravastatin and simvastatin against S. aureus, Pseudomonas aeruginosa, Escherichia coli and Enterococcus faecalis. Simvastatin was the only agent with activity against clinical isolates and reference strains of methicilin-sensitive S. aureus (MSSA) and methicillin-resistant S. aureus (MRSA). Thus, the effects of simvastatin on the growth, viability and biofilm formation of S. aureus were tested. In addition, a possible synergistic effect between simvastatin and vancomycin was evaluated. Simvastatin's MIC was 15.65 µg/mL for S. aureus 29213 and 31.25 µg/mL for the other strains of S. aureus. The effect of simvastatin was bactericidal at 4xMIC and bacteriostatic at the MIC concentration. No synergistic effect was found between simvastatin and vancomycin. However, the results obtained against S. aureus biofilms showed that, in addition to inhibiting adhesion and biofilm formation at concentrations from 1/16xMIC to 4xMIC, simvastatin was also able to act against mature biofilms, reducing cell viability and extra-polysaccharide production. In conclusion, simvastatin showed pronounced antimicrobial activity against S. aureus biofilms, reducing their formation and viability.


Asunto(s)
Antibacterianos/farmacología , Biopelículas/efectos de los fármacos , Staphylococcus aureus Resistente a Meticilina/efectos de los fármacos , Simvastatina/farmacología , Vancomicina/farmacología , Anticolesterolemiantes/farmacología , Atorvastatina/farmacología , Adhesión Bacteriana/efectos de los fármacos , Biopelículas/crecimiento & desarrollo , Reposicionamiento de Medicamentos , Enterococcus faecalis/efectos de los fármacos , Enterococcus faecalis/crecimiento & desarrollo , Escherichia coli/efectos de los fármacos , Escherichia coli/crecimiento & desarrollo , Staphylococcus aureus Resistente a Meticilina/crecimiento & desarrollo , Pruebas de Sensibilidad Microbiana , Viabilidad Microbiana/efectos de los fármacos , Pravastatina/farmacología , Pseudomonas aeruginosa/efectos de los fármacos , Pseudomonas aeruginosa/crecimiento & desarrollo
11.
Rev. odontol. UNESP (Online) ; 49: e20200075, 2020. tab, ilus
Artículo en Portugués | LILACS, BBO | ID: biblio-1251980

RESUMEN

Introdução: Tratamentos têm sido propostos para a peri-implantite com o objetivo de descontaminar a superfície dos implantes, removendo microrganismos que podem estar associados à doença. Objetivo: O objetivo deste estudo foi avaliar a ação in vitro de diferentes métodos de aplicação de digluconato de clorexidina (CLX) na descontaminação de discos de titânio (Ti) com microtopografia e seu efeito físico-químico sobre a superfície. Material e método: Vinte discos de Ti foram expostos a inóculo de Escherichia coli por 24 horas. Foram distribuídos em quatro grupos de descontaminação (n=5): 1 - um minuto de exposição à solução de CLX 0,12%; 2 - dois minutos de exposição à solução de CLX 0,12%; 3 - esfregaço durante um minuto com gel de CLX 1%; 4 - esfregaço durante um minuto com gel de CLX 2%. O produto de cada disco foi diluído e plaqueado individualmente. Após 24 horas, realizou-se contagem das unidades de colônias formadas (UFC). Resultado: O grupo com o menor número de crescimento de UFC foi o grupo 4 (0,20±0,37), com apenas UFC em uma das amostras. Seguido do grupo 2 (0,40±0,73), grupo 1 (18,60±33,96). O grupo 3 apresentou as maiores quantidades de UFC (36,07±41,39). Em todas as amostras, foi possível observar uma diminuição estatisticamente significante da concentração superficial de Ti, assim como um aumento de oxigênio. Conclusão: Pode-se concluir que o uso de CLX gel a 2% em superfícies de Ti com microtopografia contaminadas com E. coli propicia a eliminação das UFC e que sua aplicação resulta em diminuição do percentual de Ti e aumento do teor de O.


Introduction: Treatments have been proposed for peri-implantitis aiming to decontaminate the implants` surface removing microorganisms associated with the disease. Objective: The objective of this study was to evaluate the in vitro action of application of chlorhexidine digluconate (CLX) in the decontamination of titanium (Ti) discs with microtopography and its chemical-physical effect on the surface. Material and method: Twenty Ti discs were exposed to the Escherichia coli inoculum for 24 hours. Distributed equally in 4 decontamination groups (n = 5): 1- one minute of exposure to the 0.12% CLX solution; 2- two minutes of exposure to the 0.12% CLX solution; 3- smear for 1 minute with 1% CLX gel; and 4- smearing for 1 minute with 2% CLX gel. The product was diluted and plated individually. After 24 hours, colony units formed (CFU) were counted. Result: The group with the lowest number of CFU growth was group 4 (0.20 ± 0.37) with only one CFU in one of the samples. Followed by group 2 (0.40 ± 0.73), group 1 (18.60 ± 33.96), and group 3, which presented the highest amounts of CFU (36.07 ± 41.39). In all samples it was possible to observe a statistically significant decrease in the surface concentration of Ti, as well as an increase in oxygen. Conclusion: It can be concluded that the use of 2% CLX gel on Ti surfaces with microtopography contaminated with E.coli allows the elimination of CFU, and that its application results in a decrease in the percentage of Ti and an increase in the content of O.


Asunto(s)
Técnicas In Vitro , Clorhexidina , Descontaminación , Implantación Dental , Fenómenos Químicos , Periimplantitis , Oxígeno , Titanio , Escherichia coli
12.
Case Rep Dent ; 2014: 520169, 2014.
Artículo en Inglés | MEDLINE | ID: mdl-24715996

RESUMEN

Teeth with vertical root fracture (VRF) have complete or incomplete fractures that begin in the root and extend toward the occlusal surface. The most frequent causes of VRF originate from physical trauma, occlusal prematurity, inadequate endodontic treatment, and iatrogenic causes. Diagnose is difficult and delay can cause stomatognathic system problem. The purpose of this case report was to evaluate immediate implant placement after extraction of teeth with vertical root fracture. For the 1st case, the VRF in 1st left lower molar was confirmed during surgical flap and at the same time, the tooth was removed and immediate implant was placed. For the 2nd case, the VRF 1st left lower molar was confirmed during endodontic access and at the same appointment, the tooth was removed and the immediate implant is placed. Several studies have shown that immediate implants have similar success rates when compared with late implants. Consider that this approach is a safe procedure with favorable prognosis. In cases of VRF, the main factor to be considered is the presence of adequate bone support and immediate implants can preserve the vertical bone height, adding the fact that good patient compliance reduces the number of surgical interventions and promotes the functionality of stomatognathic system.

13.
Biomed Mater ; 8(3): 035007, 2013 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-23558249

RESUMEN

This study investigated the effects of the morphology and physicochemical properties of calcium phosphate (CaP) nanoparticles on osteogenesis. Two types of CaP nanoparticles were compared, namely amorphous calcium phosphate (ACP) nano-spheres (diameter: 9-13 nm) and poorly crystalline apatite (PCA) nano-needles (30-50 nm × 2-4 nm) that closely resemble bone apatite. CaP particles were spin-coated onto titanium discs and implants; they were evaluated in cultured mouse calvarial osteoblasts, as well as after implantation in rabbit femurs. A significant dependence of CaP coatings was observed in osteoblast-related gene expression (Runx2, Col1a1 and Spp1). Specifically, the PCA group presented an up-regulation of the osteospecific genes, while the ACP group suppressed the Runx2 and Col1a1 expression when compared to blank titanium substrates. Both the ACP and PCA groups presented a more than three-fold increase of calcium deposition, as suggested by Alizarin red staining. The removal torque results implied a slight tendency in favour of the PCA group. Different forms of CaP nanostructures presented different biologic differences; the obtained information can be used to optimize surface coatings on biomaterials.


Asunto(s)
Sustitutos de Huesos , Fosfatos de Calcio , Nanopartículas , Osteogénesis , Titanio , Animales , Apatitas/química , Sustitutos de Huesos/química , Fosfatos de Calcio/química , Células Cultivadas , Materiales Biocompatibles Revestidos/química , Expresión Génica , Ensayo de Materiales , Ratones , Microscopía Electrónica de Rastreo , Nanopartículas/química , Osteoblastos/citología , Osteoblastos/metabolismo , Osteotomía , Conejos
14.
J Appl Oral Sci ; 20(5): 550-5, 2012.
Artículo en Inglés | MEDLINE | ID: mdl-23138742

RESUMEN

UNLABELLED: An important parameter for the clinical success of dental implants is the formation of direct contact between the implant and surrounding bone, whose quality is directly influenced by the implant surface roughness. A screw-shaped design and a surface with an average roughness of Sa of 1-2 µm showed a better result. The combination of blasting and etching has been a commonly used surface treatment technique. The versatility of this type of treatment allows for a wide variation in the procedures in order to obtain the desired roughness. OBJECTIVES: To compare the roughness values and morphological characteristics of 04 brands of implants, using the same type of surface treatment. In addition, to compare the results among brands, in order to assess whether the type of treatment determines the values and the characteristics of implant surface roughness. MATERIAL AND METHODS: Three implants were purchased directly from each selected company in the market, i.e., 03 Brazilian companies (Biomet 3i of Brazil, Neodent and Titaniumfix) and 01 Korean company (Oneplant). The quantitative or numerical characterization of the roughness was performed using an interferometer. The qualitative analysis of the surface topography obtained with the treatment was analyzed using scanning electron microscopy images. RESULTS: The evaluated implants showed a significant variation in roughness values: Sa for Oneplant was 1.01 µm; Titaniumfix reached 0.90 µm; implants from Neodent 0.67 µm, and Biomet 3i of Brazil 0.53 µm. Moreover, the SEM images showed very different patterns for the surfaces examined. CONCCLUSIONS: The surface treatment alone is not able to determine the roughness values and characteristics.


Asunto(s)
Implantación Dental Endoósea/métodos , Implantes Dentales , Titanio/química , Grabado Ácido Dental , Análisis de Varianza , Humanos , Ensayo de Materiales , Microscopía Electrónica de Rastreo , Valores de Referencia , Estadísticas no Paramétricas , Propiedades de Superficie
15.
Acta Biomater ; 8(12): 4438-46, 2012 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-22842030

RESUMEN

Mesoporous materials are of high interest as implant coatings to receive an enhanced osseointegration. In this study, titanium implants coated with mesoporous TiO(2) thin films have been evaluated both in vitro and in vivo. Material characterization showed that, with partly crystalline TiO(2) (anatase), long-range-ordered hydrophilic mesoporous thin films with a pore size of 6nm were obtained. Evaluation of the mechanical resistance showed that the films were robust enough to withstand the standard implantation procedure. In vitro apatite formation was studied using simulated body fluids, showing that the pores are accessible for ions and that formation of apatite was increased due to the presence of the mesopores. An in vivo study using a rabbit model was executed in which the removal torque and histomorphometry were evaluated. The results show that the biomechanical stability of the TiO(2) coating was unaffected by the presence of mesopores and that osseointegration was achieved without any signs of inflammation.


Asunto(s)
Sustitutos de Huesos/química , Ensayo de Materiales , Oseointegración , Titanio/química , Animales , Apatitas/química , Apatitas/metabolismo , Porosidad , Conejos
16.
J Biomed Mater Res A ; 100(10): 2629-36, 2012 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-22615216

RESUMEN

Implant topography is an important factor that influences many cell types. To understand the role of topography in the inflammatory events, we evaluated the response of human gingival fibroblasts (HGFs) by the release pattern of cytokines. HGFs were cultured on Ti discs for 24 and 48 h. Four different surface treatments were used: machining method (turned), blasting followed by an acid-etching method (BAE), oxidative nanopatterning (ON) method, and an association of blasting followed by an acid-etching plus oxidative nanopatterning (BAE+ON) method. Extracellular levels of IL-6, IL-8, transforming growth factor beta (TGF-ß), IL-4, and IL-10 were measured by enzyme-linked immunosorbant assay. Increased levels of IL-6 and IL-8 were observed in all surfaces after 24 h which decreased after 48 h. BAE, ON, and BAE+ON surfaces showed a reduction in IL-6 levels compared with the turned after 48 h (p < 0.05). On one hand, IL-8 production was lower in BAE+ON in comparison to the turned surface (p < 0.05). On the other hand, IL-4 showed increased levels with 48 h, which were significantly different between turned, BAE, and ON surfaces, but not with BAE+ON. Additionally, TGF-ß and IL-10 production were not detected. This study indicates that nanotopography might be important in the modulation of the inflammatory response in cultured HGFs.


Asunto(s)
Citocinas/biosíntesis , Fibroblastos/metabolismo , Encía/citología , Nanopartículas/química , Titanio/química , Grabado Ácido Dental , Células Cultivadas , Fibroblastos/citología , Humanos , Imagenología Tridimensional , Implantes Experimentales , Interferometría , Microscopía de Fuerza Atómica , Nanopartículas/ultraestructura , Oxidación-Reducción , Espectroscopía de Fotoelectrones , Propiedades de Superficie
17.
Int J Biomater ; 2012: 305638, 2012.
Artículo en Inglés | MEDLINE | ID: mdl-23304151

RESUMEN

Aim. This study aimed to observe the morphological and molecular effect of laminin-1 doping to nanostructured implant surfaces in a rabbit model. Materials and Methods. Nanostructured implants were coated with laminin-1 (test; dilution, 100 µg/mL) and inserted into the rabbit tibiae. Noncoated implants were used as controls. After 2 weeks of healing, the implants were removed and subjected to morphological analysis using scanning electron microscopy (SEM) and gene expression analysis using the real-time reverse transcriptase-polymerase chain reaction (RT-PCR). Results. SEM revealed bony tissue attachment for both control and test implants. Real-time RT-PCR analysis showed that the expression of osteoblast markers RUNX-2, osteocalcin, alkaline phosphatase, and collagen I was higher (1.62-fold, 1.53-fold, 1.97-fold, and 1.04-fold, resp.) for the implants modified by laminin-1 relative to the control. All osteoclast markers investigated in the study presented higher expression on the test implants than controls as follows: tartrate-resistant acid phosphatase (1.67-fold), calcitonin receptor (1.35-fold), and ATPase (1.25-fold). The test implants demonstrated higher expression of inflammatory markers interleukin-10 (1.53-fold) and tumour necrosis factor-α (1.61-fold) relative to controls. Conclusion. The protein-doped surface showed higher gene expression of typical genes involved in the osseointegration cascade than the control surface.

18.
Dental press j. orthod. (Impr.) ; 21(2): 95-101, Mar.-Apr. 2016. tab, graf
Artículo en Inglés | LILACS | ID: lil-782945

RESUMEN

ABSTRACT Objective: This study evaluated alveolar bone loss around mandibular incisors, induced by the Herbst appliance. Methods: The sample consisted of 23 patients (11 men, 12 women; mean age of 15.76 ± 1.75 years), Class II, Division 1 malocclusion, treated with the Herbst appliance. CBCT scans were obtained before treatment (T0) and after Herbst treatment (T1). Vertical alveolar bone level and alveolar bone thickness of mandibular incisors were assessed. Buccal (B), lingual (L) and total (T) bone thicknesses were assessed at crestal (1), midroot (2) and apical (3) levels of mandibular incisors. Student's t-test and Wilcoxon t-test were used to compare dependent samples in parametric and nonparametric cases, respectively. Pearson's and Spearman's rank correlation analyses were performed to determine the relationship of changes in alveolar bone thickness. Results were considered at a significance level of 5%. Results: Mandibular incisors showed no statistical significance for vertical alveolar bone level. Alveolar bone thickness of mandibular incisors significantly reduced after treatment at B1, B2, B3, T1 and significantly increased at L2. The magnitude of the statistically significant changes was less than 0.2 mm. The changes in alveolar bone thickness showed no statistical significance with incisor inclination degree. Conclusions: CBCT scans showed an association between the Herbst appliance and alveolar bone loss on the buccal surface of mandibular incisors; however, without clinical significance.


RESUMO Introdução: este estudo avaliou a perda óssea alveolar ao redor dos incisivos inferiores induzida pelo aparelho de Herbst. Métodos: a amostra foi composta por 23 pacientes (11 homens e 12 mulheres; média de idade 15,76 ± 1,75 anos), má oclusão de Classe II, divisão 1, tratados com aparelho de Herbst. TCFCs foram realizadas antes do tratamento (T0) e após o tratamento (T1) com o Herbst. A altura e a espessura óssea alveolar dos incisivos inferiores foram avaliadas. As espessuras ósseas vestibular (V), lingual (L) e total (T) foram mensuradas nos terços cervical (1), médio (2) e apical (3) dos incisivos inferiores. O teste t de Student e o teste t de Wilcoxon compararam as amostras dependentes nos casos paramétricos e não paramétricos, respectivamente. As análises de Pearson e Spearman determinaram a correlação entre as alterações na espessura do osso alveolar. Os resultados foram considerados para um nível de significância de 5%. Resultados: os incisivos inferiores não apresentaram significância estatística para a altura óssea alveolar. Após o tratamento, a espessura óssea alveolar dos incisivos inferiores reduziu-se significativamente em V1, V2, V3 e T1 e aumentou significativamente em L2. A quantidade da alteração óssea significativa foi menor que 0,2mm. As alterações na espessura óssea alveolar não apresentam correlação estatisticamente significativa com o grau de inclinação do incisivo. Conclusões: as imagens de TCFC demonstram associação entre o uso do aparelho de Herbst e a perda óssea alveolar no lado vestibular dos incisivos inferiores; entretanto, sem significância clínica.


Asunto(s)
Humanos , Masculino , Femenino , Adolescente , Adulto , Pérdida de Hueso Alveolar/diagnóstico por imagen , Aparatos Ortodóncicos Funcionales , Tomografía Computarizada de Haz Cónico , Maloclusión Clase II de Angle/terapia , Maloclusión Clase II de Angle/diagnóstico por imagen , Técnicas de Movimiento Dental , Brasil , Periodoncio/diagnóstico por imagen , Estudios Retrospectivos , Estudios de Seguimiento , Diseño de Aparato Ortodóncico , Encía/diagnóstico por imagen , Incisivo/diagnóstico por imagen , Mandíbula/diagnóstico por imagen
19.
Acta Biomater ; 7(12): 4229-34, 2011 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-21816237

RESUMEN

Nanostructures on implant surfaces have been shown to enhance osseointegration; however, commonly used evaluation techniques are probably not sufficiently sensitive to fully determine the effects of this process. This study aimed to observe the osseointegration properties of nanostructured calcium phosphate (CaP)-coated implants, by using a combination of three-dimensional imaging and conventional histology. Titanium implants were coated with stable CaP nanoparticles using an immersion technique followed by heat treatment. Uncoated implants were used as the control. After topographical and chemical characterizations, implants were inserted into the rabbit femur. After 2 and 4weeks, the samples were retrieved for micro-computed tomography and histomorphometric evaluation. Scanning electron microscopy evaluation indicated that the implant surface was modified at the nanoscale by CaP to obtain surface textured with rod-shaped structures. Relative to the control, the bone-to-implant contact for the CaP-coated implant was significantly higher at 4weeks after the implant surgery. Further, corresponding 3-D images showed active bone formation surrounding the implant. 3-D quantification and 2-D histology demonstrated statistical correlation; moreover, 3-D quantification indicated a statistical decrease in bone density in the non-coated control implant group between 2 and 4weeks after the surgery. The application of 3-D evaluation further clarified the temporal characteristics and biological reaction of implants in bone.


Asunto(s)
Fosfatos de Calcio/química , Oseointegración , Prótesis e Implantes , Microscopía Electrónica de Rastreo , Nanopartículas , Tomografía Computarizada por Rayos X
20.
UNOPAR Cient., Ciênc. biol. saude ; 17(1): 63-66, abr. 15.
Artículo en Inglés | LILACS-Express | LILACS | ID: lil-759590

RESUMEN

O conceito de procedimentos minimamente invasivos pode ser estendido a todas as áreas da odontologia, mas a periodontia, em especial, temresultados benéficos quando da utilização desta modalidade terapêutica. Dessa forma, esta revisão de literatura teve como objetivo descrevera utilização dos procedimentos minimamente invasivos em cirurgias periodontais, seus conceitos, aplicações e possiveis beneficios. Para estarevisão de literatura, foram avaliados 682 artigos publicados entre 1950 e 2012 que abordaram o tema cirurgia periodontal minimamenteinvasiva. Destes 682 artigos, 668 não descreveram claramente os procedimentos realizados não atendendo aos critérios de inclusão e portantoforam descartados. Cuidados como iluminação adequada promovem um aumento da acuidade visual durante os procedimentos cirurgicos,assim favorecendo a precisão associada aos instrumentos microcirúrgicos especificamente concebidos e permitindo uma manipulação maisprecisa e minimamente traumática dos tecidos moles e duros. Além disso, auxilia na melhora do acesso cirúrgico, evita a remoção desnecessáriade tecidos, a optimização do desbridamento, melhora a vascularização e, por conseguinte, a possibilidade de obtenção de cicatrizaçãoprimária de feridas cirúrgicas. A abordagem microcirúrgica pode melhorar a previsibilidade dos diferentes procedimentos periodontais,proporcionar melhores resultados estéticos e causar menor desconforto pós-operatório. No entanto, poucos estudos foram realizados commetodologias estabelecidas sobre o uso de instrumentos que promovam procedimentos minimamente invasivos em periodontia. Portanto, sãonecessários estudos para determinar se as técnicas microcirúrgicas podem levar a uma diferença significativa no prognóstico da terapeuticaproposta. A maioria dos estudos encontrados na literatura são baseados em observações e experiências dos autores, que mostram claramenteque há vantagens em uma melhor iluminação, melhor visão e técnica mais controlada e menos traumática.


The concept of minimally invasive procedures can be extended to all s of dentistry. Periodontics, in particular, has been reported as oneof the areas with great benefits. This review aims to describe the use of minimally invasive procedures in periodontal surgery, its concepts,applications, and possible benefits from its use. For that, 682 articles published between 1950 and 2012 focused on minimally invasiveperiodontal surgery were evaluated. Of them, 669 studies did not describe clearly the procedures, and did not attend the inclusion criteria.The results showed that proper lighting promotes increased visual acuity during surgical procedures, favoring the precision associated withmicrosurgical instruments specifically designed, allowing a more accurate manipulation of the soft and hard tissues. Surgical access avoidsunnecessary tissues removal, optimizing the debridement, improving vascularisation, and therefore the possibility of obtaining primary healingof surgical wounds. The microsurgical approach can improve the predictability of different periodontal procedures, providing better resultsand cause less postoperative discomfort. However, few controlled methodologies on the use of instruments to promote minimally invasiveprocedures in periodontics have been found in literature. Therefore, studies are needed to determine whether microsurgical techniques can leadto a significant difference in the successful outcome. Most of the studies are based on observations and experiences of the authors, which clearlyshow that there are advantages in having better lighting, better vision, and a more controlled and less traumatic technique.

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