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1.
BMC Oral Health ; 23(1): 574, 2023 08 16.
Artigo em Inglês | MEDLINE | ID: mdl-37587482

RESUMO

INTRODUCTION: An accurate impression is an essential procedure for fabricating indirect fixed restorations. To achieve a precise final impression, the management of gingival tissue is without doubt a crucial. AIM: To evaluate the use of different gingival displacement techniques among dental clinicians and to assess their associated knowledge and technique preferences. METHODS: A self-designed survey was created electronically and sent to a list of dentists. The survey was composed of multiple sections. Participants who stated that they do not use GD methods were asked to answer the survey questions based on their knowledge. Descriptive statistics were generated, andChi-square test was used to examine the association between the different variables. RESULTS: A total of 188 dentists participated in this study. The majority 144 (76.6%) use GD in their practice. When asked which technique yields a more accurate impression with lower incidence of repeating the impression, 93 (64.6%) reported retraction cord technique with a hemostatic agent results in a higher impression accuracy, while only 14 (9.7%) declared the retraction paste technique as being more accurate. CONCLUSION: The cordless GD technique is believed to be easier, faster, and less traumatic to the gingival tissues, nevertheless, the outcome of dental impressions is believed to be more predictable with the use of conventional retraction cords and hemostatic medicaments.


Assuntos
Assistência Odontológica , Hemostáticos , Humanos , Emoções , Gengiva , Odontólogos
2.
J Prosthodont ; 31(1): 30-37, 2022 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-34378269

RESUMO

PURPOSE: The purpose of this randomized, double-blind, clinical trial was to assess the survival of endocrowns made from three different monolithic ceramic materials, and to evaluate patient satisfaction. MATERIALS AND METHODS: Fifty-three patients (sixty root canal treated molar teeth) were enrolled. Teeth were prepared to a flat butt-joint margin and randomly divided between three material groups: lithium disilicate-reinforced glass-ceramic, monolithic zirconia and polymer infiltrated hybrid ceramic. Predefined cementation protocols were used. Clinical assessment using modified United States Public Health Service (USPHS) criteria was carried out after two years by two independent clinicians blinded to the material used. Radiographic examination was conducted to check for the presence of caries, excess cement, and periapical infection. Statistical analysis was performed using the Kruskal Wallis and Wilcoxon signed-rank tests as well as the Kaplan-Meier survival estimate. RESULTS: Forty-eight patients were available for assessment after 2 years (recall rate 90.6%). The overall Kaplan-Meier survival estimate among all groups was 90.9% with no statistically significant difference between the groups (p = 0.17). Three zirconia endocrowns debonded after 9, 10 and 13 months (82.4% survival rate), while 2 hybrid ceramic endocrowns chipped/fractured (89.5% survival rate). Lithium disilicate endocrowns had a 100% survival rate. The Kruskal Wallis test revealed no statistically significant difference between the groups in the USPHS criteria ratings and the radiographic assessment (P>0.05). Patient satisfaction ranged from 82.3% in the zirconia group to 100% in both the lithium disilicate and hybrid ceramic groups. CONCLUSIONS: Endocrowns provide a predictable option for the restoration of endodontically treated molar teeth in the short term. Lithium disilicate-reinforced ceramic had fewer complications and required less intervention compared with zirconia and hybrid ceramics. Long-term follow-up is required to substantiate these study results.


Assuntos
Coroas , Falha de Restauração Dentária , Cerâmica , Desenho Assistido por Computador , Porcelana Dentária , Análise do Estresse Dentário , Humanos , Teste de Materiais
3.
BMC Med Educ ; 21(1): 151, 2021 Mar 08.
Artigo em Inglês | MEDLINE | ID: mdl-33685451

RESUMO

BACKGROUND: The quarantine associated with the COVID-19 pandemic forced dental schools to suspend their clinical training and to shift to distant learning methods. The aim of this study is to investigate the impact of quarantine on the self-perceived preparedness of dental graduates and to explore the efficacy of online education from students' perspectives. METHODS: The questionnaire distributed to dental students comprised of two main sections. The first part covered the online education experience, and the second part measured the level of self-perceived preparedness for a range of cognitive, communication and professional skills. RESULTS: The survey yielded a response rate of 72%. The majority of students (77%) agreed that they missed educational experiences as a result of the lockdown. More than half of them felt less motivated to follow-up with distant e-learning and believed that online assessment is not a good method for evaluation. A high percentage of the students (66%) thought that online group discussions had a positive value while 67% preferred online lectures compared to theatre lectures. Majority of students particularly 5th year (78.7%) (p < 0.001) stated that the quarantine increased their collaboration with their colleagues. According to 87% of students, the experience most negatively affected was their clinical training. In general, students showed satisfactory self-perceived preparedness related to a range of attributes and professional skills. CONCLUSIONS: The data showed that students partially appreciated the online system, whereas they did not consider it a substitute for face to face clinical practice. The overall self-perceived preparedness level was promising; however students had reservations regarding independent practice following graduation.


Assuntos
COVID-19/epidemiologia , Educação em Odontologia , Educação a Distância/métodos , Pandemias , Competência Profissional , Estudantes de Odontologia/psicologia , Feminino , Humanos , Jordânia/epidemiologia , Masculino , Motivação , Quarentena , SARS-CoV-2 , Autoimagem , Autoavaliação (Psicologia)
4.
Eur J Dent Educ ; 25(1): 207-214, 2021 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-33245624

RESUMO

PURPOSE: Graduating confident students who are able to flourish and develop in their future careers is an importance outcome of the dental education. This study aims to evaluate self-perceived level of confidence of fifth-year dental students in different restorative-related tasks and the relationship between their clinical training and its corresponding confidence. METHODS: Fifth-year graduate dental students (n = 202) were asked to fill a questionnaire that rated their level of confidence in different clinical restorative dentistry tasks. Additionally, they were asked about the number of times they performed tasks prior to attempting the equivalent competency and in which sub-specialty they felt the most confident. RESULTS: Completed responses were received from 120 students giving a response rate of 59%. Students felt the most prepared and confident in direct restorations and simple endodontic treatment, and they seemed less confident in indirect restorations and complex endodontic treatment. Regarding the steps of indirect restorations, students expressed least confidence in crown preparation compared to impression making and try-in procedures (P < .05). Students rated their confidence highest in operative dentistry, followed by endodontics and lastly fixed prosthodontics. CONCLUSION: The results highlight the areas in which students exhibit the least confidence. Enhancement of student clinical skills and directed exposure is necessary to raise the level of perceived confidence which will reflect positively on their current and future professional performance.


Assuntos
Endodontia , Estudantes de Odontologia , Competência Clínica , Assistência Odontológica , Dentística Operatória , Educação em Odontologia , Humanos
5.
Int J Dent ; 2020: 8842008, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-32908511

RESUMO

Background/Objectives. The holistic methodology in education has been widely appreciated and implicated in dental schools in the last decade. Our department of conservative dentistry decided to reform the educational model of teaching from a traditional requirement-based model to a hybrid model incorporating comprehensive care treatment. The aim of our study was to assess students' confidence and perspectives regarding the benefits of a comprehensive model of teaching. Materials and Methods. A questionnaire was distributed at the end of the academic year 2018-2019 and designed to investigate students' opinions on the benefits of the new model of teaching, as well as difficulties encountered and possible shortcomings. In addition, self-perceived confidence level was assessed for the purpose of comparing confidence during supervised tasks versus confidence during comprehensive patient care. Results. Complete responses were gathered from 127 students out of 202, giving a response rate of 63%. The majority of students believed that the comprehensive model of teaching allowed them to better address patients' needs, gave higher satisfaction, positively influenced self-confidence, permitted greater exposure to clinical techniques, and enhanced reasoning and analytical skills. However, their confidence was still lower in comprehensive patient management when compared to supervised tasks. Conclusion. Our students showed an appreciation of the comprehensive care model. Self-learning and didactic skills were enhanced. It would, therefore, be beneficial to adapt this methodology to earlier years and other disciplines to enhance the effectiveness of education and achievement of learning outcomes.

6.
J Dent Educ ; 84(12): 1418-1425, 2020 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-32803774

RESUMO

PURPOSE: The aim of this study was to investigate the perceived satisfaction of optional pairing in undergraduate clinical dental training of fourth- and fifth-year dental students and newly graduated intern dentists in the subject of conservative dentistry and endodontics. METHODS: Data were collected through a paper-based 2-part questionnaire. The first part was made of 3 questions; gender, undergraduate dental year, and grade point average (GPA). The second part involved 9 questions about assistant student-year level preference, satisfaction of optional pairing and main advantages and disadvantages of pairing. Statistical analysis was performed using descriptive statistics and Chi-square test to investigate any statistically significant differences. RESULTS: A total of 92.4% were satisfied with optional clinical pairing. Satisfied respondents reported most prevalent advantages were speeding things up (88.5%) and helping in transferring instruments and materials (85.6%). Unsatisfied respondents reported the most prevalent disadvantages were like to work independently (56.8%) and the assistant was not always cooperative (32.4%). Students with low grade point averages (GPAs) felt incompetent to work in pairs compared with high GPA students (P = 0.001). Only 32.4% of participants thought that the assistant student should be given an evaluation mark. About 75% of respondents reported that clinical pairing improved their diagnostic skills and treatment planning. CONCLUSIONS: Optional pairing in clinical dental training had a high satisfaction percentage. Allowing students to choose their own assistants may reduce pairing disadvantages and enhance its advantages. Students may gain a mentoring benefit from being encouraged to optionally pair with similar or higher study-year students.


Assuntos
Endodontia , Satisfação Pessoal , Educação em Odontologia , Avaliação Educacional , Humanos , Estudantes de Odontologia
7.
Dent Res J (Isfahan) ; 17(2): 92-99, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-32435430

RESUMO

BACKGROUND: Immediate dental implants placement and loading utilizing definitive abutments might save time and cost when an esthetic final result is anticipated. The objective of this prospective clinical trial was to evaluate the esthetic outcome of immediate implantation and immediate nonfunctional loading utilizing definitive abutments, with and without bony substitutes filling the peri-implant gap. MATERIALS AND METHODS: In this clinical trial study a total of 11 implants were placed utilizing a flapless immediate post extraction approach in the maxilla (second premolar to second premolar). Atraumatic extraction was performed and implants were immediately placed. The gap was either left without grafting or filled with particulate bone material. Immediate nonfunctional loading was performed utilizing a definitive abutment. The pink esthetic scores (PESs) were assessed preoperatively, at 1- and 2-year follow-up periods. Dental casts were obtained at respective time intervals; scanned, registered, and closest point distances were measured. For all statistical tests, value of P = 0.05 was set as a statistical significance level. RESULTS: The mean of PES at baseline was 9.4 ± 1.69, at 1 year was 9.5 ± 2.07, at 2 years was 10.2 ± 2.75, for the graft group 10.3 ± 2.8, and for nongrafting group was 10.2 ± 2.59. There were no statistically significant differences in PESs at baseline when compared to 1- and 2-year intervals, and for grafting group versus nongrafting group (P = 0.24). Distances between the two time points for all cases were <1 mm in all reference planes. CONCLUSION: Immediate placement and nonfunctional loading utilizing a definitive abutment appear to result in a stable result as far as esthetic outcome and alveolar process sufficiency are concerned.

8.
J. oral res. (Impresa) ; 8(4): 298-304, nov. 5, 2019. tab, ilus
Artigo em Inglês | LILACS | ID: biblio-1145351

RESUMO

Objective: the purpose of this multicenter retrospective study was to report on survival, success, and complication rates in monolithic zirconia restorations on teeth and implants. Materials and Methods: data on 671 monolithic zirconia restorations was collected by five prosthodontists from three different specialty practice centers, including a dental school and two private practice centers. Restorations included single crowns and multiple-unit fixed dental prostheses on teeth and implants in the posterior area (premolar and molars). Follow-up time was up to 62 months. Results: mean follow-up time was 28.1±12.9 months. A total of 671 units, 534 single crowns, and 137 multi-unit restorations. Cumulative survival and success rates at 5 years were 97.4%, and 93.8% respectively. Complications presented in 11 restorations out of 671 and included: decementation, abutment screw loosening, restoration crack, restoration fracture, and tooth fracture. No significant differences were observed between tooth-supported and implant-supported restoration (p=0.42), single crowns and multiple-unit restorations (p=0.07), bruxers and non-bruxers (p=0.57). Patients with group function occlusal scheme had significantly less survival rates (p=0.001). Conclusion: the use of monolithic zirconia for restorations on the posterior teeth and implants seems to be promising as it provides a durable solution with a low rate of complications.


Objetivo: el propósito de este estudio retrospectivo multicéntrico fue informar sobre las tasas de supervivencia, éxito y complicaciones en restauraciones monolíticas de circonio en dientes e implantes. Materiales y Métodos: cinco prostodoncistas recolectaron datos de 671 restauraciones monolíticas de zirconia de tres centros de práctica especializados: una escuela de odontología y dos centros de práctica privados. Las restauraciones incluyeron coronas individuales y prótesis dentales fijas de unidades múltiples en dientes e implantes en el área posterior (premolares y molares). El tiempo de seguimiento fue de hasta 62 meses. Resultados: el tiempo medio de seguimiento fue de 28,1±12,9 meses. Un total de 671 unidades, 534 coronas individuales y 137 restauraciones de unidades múltiples. La supervivencia acumulada y las tasas de éxito a los 5 años fueron del 97,4% y del 93,8%, respectivamente. Las complicaciones se presentaron en 11 restauraciones de 671 e incluyeron: fracaso del cementado, aflojamiento del tornillo del pilar, grieta en la restauración, fractura de restauración y fractura de dientes. No se observaron diferencias significativas entre la restauración con soporte dental y con implante (p=0,42), coronas individuales y restauraciones de unidades múltiples (p=0,07), pacientes con bruxismo y sin bruxismo (p=0,57). Los pacientes con esquema oclusal de función grupal tuvieron tasas de supervivencia significativamente menores (p= 0,0 01). Conclusión: el uso de zirconia monolítica para restauraciones en los dientes posteriores y en implantes parece ser prometedor, ya que proporciona una solución duradera con una baja tasa de complicaciones.


Assuntos
Humanos , Zircônio/química , Implantes Dentários para Um Único Dente , Implantação Dentária Endóssea , Fraturas dos Dentes , Estudos Retrospectivos , Resultado do Tratamento , Retenção em Prótese Dentária/estatística & dados numéricos , Coroas , Cimentos Dentários
9.
Dent Traumatol ; 34(6): 394-400, 2018 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-30053348

RESUMO

BACKGROUND/AIM: Social media sites such as Facebook are increasingly used to obtain healthcare-related information. The aim of this study was to examine Facebook content on dental trauma and to assess public engagement with this content. MATERIALS AND METHODS: An anonymous account was created to search Facebook for information on dental trauma using the key words "dental trauma," "broken tooth," "tooth fracture," and "tooth trauma" over a period of 1 year (from February 27, 2017, to February 27, 2018). The content was analyzed with regard to demographic characteristics, topic domains, and public engagement. RESULTS: A total of 395 Facebook pages and 149 groups were identified, but only one page and two groups met the inclusion criteria. There were 329 posts on dental trauma during the study period. More than half of the posts were event advertisements and personal highlights (56.2%), followed by posts mentioning articles in academia (17.9%). The average yearly engagement rate was 0.25%; news posts generated the highest engagement rate (0.76%), while academic posts generated the lowest engagement rate (0.16%). The singular post that generated the highest engagement rate (2.2%) was a news post referring to a dental trauma incident suffered by a professional football player. Only 14 posts (4.3%) contained information on prevention and immediate management of dental trauma. CONCLUSIONS: Facebook information on dental trauma is limited in quantity and quality. More emphasis should be placed on posting information suitable for the layperson and concerned with the basics of prevention and immediate management of dental trauma.


Assuntos
Informação de Saúde ao Consumidor/estatística & dados numéricos , Mídias Sociais , Traumatismos Dentários , Publicidade/estatística & dados numéricos , Humanos , Comportamento de Busca de Informação
10.
Saudi Dent J ; 27(2): 70-4, 2015 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-26082572

RESUMO

OBJECTIVES: The aim of this study was to evaluate the strength of the bond between newly introduced self-adhesive resin cements and tooth structures (i.e., enamel and dentin). METHODS: Three self-adhesive cements (SmartCem2, RelyX Unicem, seT SDI) were tested. Cylindrical-shaped cement specimens (diameter, 3 mm; height, 3 mm) were bonded to enamel and dentin. Test specimens were incubated at 37 °C for 24 h. The shear bond strength (SBS) was tested in a Zwick Roll testing machine. Results were analyzed by one-way ANOVA and t-test. Statistically significant differences were defined at the α = 0.05 level. Bond failures were categorized as adhesive, cohesive, or mixed. RESULTS: The SBS values ranged from 3.76 to 6.81 MPa for cements bonded to enamel and from 4.48 to 5.94 MPa for cements bonded to dentin (p > 0.05 between surfaces). There were no statistically significant differences between the SBS values to enamel versus dentin for any given cement type. All cements exhibited adhesive failure at the resin/tooth interface. CONCLUSIONS: Regardless of their clinical simplicity, the self-adhesive resin cements examined in this study exhibit limited bond performance to tooth structures; therefore, these cements must be used with caution.

11.
J Prosthet Dent ; 111(5): 411-5, 2014 May.
Artigo em Inglês | MEDLINE | ID: mdl-24355505

RESUMO

STATEMENT OF PROBLEM: Many self-adhesive cements have been introduced in the past few years, with little or no data regarding their clinical performance. This study investigated the shear bond strength of some recently introduced self-adhesive resin cements. PURPOSE: The purpose of this study was to evaluate the shear bond strength of self-adhesive and conventional resin-based cements to a base metal alloy. MATERIAL AND METHODS: Four groups (10-12 each) that comprised 3 self-adhesive cements (SmartCem2; RelyX Unicem; seT SDI) and a conventional resin-based cement (RelyX ARC) were tested. Cylindrical cement specimens (diameter, 3 mm; height, 3 mm) were applied to nickel-free base metal alloy (Sheradent) disks with a diameter of 12 mm, and the surface was treated with airborne-particle abrasion of 50 µm aluminum oxide. The metal disks were fixed in brass molds specifically designed for the shear bond test device. Test specimens were incubated at 37°C for 24 hours and then the shear bond was tested with a Zwick Roll testing machine at a 0.8 mm/min cross-head speed. In addition, bond failures were investigated and categorized as adhesive, cohesive, or mixed. Shear bond strengths were calculated by dividing the maximum debonding force over the cross-sectional area of each specimen. One-way ANOVA and the Tukey (honestly significant difference) post hoc test were used to test statistical significant differences among the groups (α=.05). RESULTS: Statistical analysis showed significant differences among different resin cements (F=14.34, P<.001). The highest mean shear bond strength was observed for SmartCem2 (14.18 MPa), and the lowest was reported for seT (3.52 MPa). The observed failure mode in all the materials was adhesive in nature, which occurred at the resin-metal interface. CONCLUSIONS: The early bond strength of self-adhesive resin cements varied significantly among the tested materials. SmartCem2 showed the highest bond strength, which was 4 times the strength observed for seT SDI.


Assuntos
Ligas de Cromo/química , Colagem Dentária , Cimentos de Resina/química , Resinas Acrílicas/química , Adesividade , Óxido de Alumínio/química , Bis-Fenol A-Glicidil Metacrilato/química , Corrosão Dentária/métodos , Análise do Estresse Dentário/instrumentação , Humanos , Teste de Materiais , Metacrilatos/química , Polietilenoglicóis/química , Ácidos Polimetacrílicos/química , Poliuretanos/química , Resistência ao Cisalhamento , Estresse Mecânico , Propriedades de Superfície , Temperatura , Fatores de Tempo
12.
J Dent Educ ; 77(1): 99-104, 2013 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-23314473

RESUMO

This study at the Faculty of Dentistry, University of Jordan investigated and evaluated students' attitudes and opinions after attempting a dental objective structured clinical examination (OSCE) for the first time. The OSCE consisted of sixty-seven stations for fourth-year dental students. After the exam, students were asked to voluntarily complete a questionnaire designed to evaluate their attitudes and opinions about the exam. Of the 134 students who participated in the OSCE, 93.2 percent completed the questionnaire; 43.4 percent said they found the exam difficult and 56.6 percent found it easy (p=0.147). Seventy percent reported that the exam was objective, while 30 percent did not (p<0.001); 65.5 percent indicated that it was a better test than traditional patient-based tests, whereas 34.5 percent did not (p<0.001). Sixty-eight percent stated that there were too many stations, while 30.9 percent stated the number of stations was appropriate and 0.8 percent stated there were too few (p<0.001). Of these respondents, 75.6 percent reported the exam was organized, whereas 21.1 percent said the exam was not very well organized and 3.3 percent said the exam was not organized at all (p<0.001). Overall, the students responded that the OSCE was able to test their clinical judgment and skills and it was a better method for evaluating their clinical skills; most preferred to have such tests in the future. Although the students reported the exam had too many stations, they perceived that it was well organized and that the time allocated for each station was appropriate. These dental students perceived that the OSCE was a suitable method to test operative dentistry clinical judgment and skills.


Assuntos
Educação em Odontologia , Avaliação Educacional , Estudantes de Odontologia/psicologia , Atitude , Avaliação Educacional/métodos , Feminino , Humanos , Jordânia , Masculino , Inquéritos e Questionários
13.
Biomaterials ; 25(25): 5621-30, 2004 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-15159078

RESUMO

Since bone repair may occur, following endochondral ossification, we have investigated the behaviour of chondrocytes isolated from nasal septum cartilage of foetal rats and cultured up to 21 days in the presence of a melt-derived bioactive glass (Bioglass 45S5) and a less reactive glass with 60 wt% silica content (60S). In both cultures, chondrocytes proliferate and form typical cartilaginous nodules on day 5 of cultures. However, on day 12, the nodules in contact with 45S5 granules became darker than in 60S cultures, corresponding to the emergence of matrix biomineralization. Transmission electron microscopy showed a collagen-rich matrix composed of densely packed fibres and mineralized foci formed of needle-shaped crystals in contact with an electron-dense layer located at the periphery of the material. The specific activity of alkaline phosphatase was significant higher in 45S5 cultures on day 15 than in 60S cultures. Real time RT-PCR was used to monitor gene expression levels of specific chondrogenic markers. The transcription factor Sox9 was expressed throughout the culture period, but with no significant differences between the two kinds of cultures. In contrast, Runx2 expression was higher in experiment cultures on day 12. Type II collagen mRNA and aggrecan, showed an almost similar expression pattern with a strong expression at the beginning of cultures but higher in experiment cultures. Indian hedgehog was strongly expressed between day 9 and 12 with a significant stimulation in 45S5 cultures. Similarly, type X collagen mRNA seemed to be up-regulated in 45S5 cultures on day 20. In conclusion, this study shows hat 45S5 Bioglass has the ability to support the growth of chondrocytes and to stimulate some chondrogenic molecular markers.


Assuntos
Cerâmica/farmacologia , Condrócitos/efeitos dos fármacos , Expressão Gênica/efeitos dos fármacos , Agrecanas , Fosfatase Alcalina/metabolismo , Animais , Diferenciação Celular/efeitos dos fármacos , Células Cultivadas , Condrócitos/metabolismo , Condrócitos/ultraestrutura , Colágeno Tipo II/genética , Colágeno Tipo X/genética , Subunidade alfa 1 de Fator de Ligação ao Core , Matriz Extracelular/metabolismo , Proteínas da Matriz Extracelular/genética , Expressão Gênica/genética , Vidro , Proteínas Hedgehog , Proteínas de Grupo de Alta Mobilidade/genética , Lectinas Tipo C , Microscopia Eletrônica de Transmissão , Microscopia de Contraste de Fase , Septo Nasal/citologia , Proteínas de Neoplasias/genética , Proteoglicanas/genética , Ratos , Ratos Sprague-Dawley , Reação em Cadeia da Polimerase Via Transcriptase Reversa , Fatores de Transcrição SOX9 , Transativadores/genética , Fatores de Transcrição/genética
14.
Connect Tissue Res ; 43(2-3): 524-8, 2002.
Artigo em Inglês | MEDLINE | ID: mdl-12489209

RESUMO

In this study, we investigated the behavior of fetal rat osteoblasts cultured up to 23 days on a bioactive apatite-wollastonite glass-ceramic (AW) and on the same material on which a carbonated apatite layer was formed by a biomimetic process (AWa). The specific activity of alkaline phosphatase activity was about 30% increased on AWa compared to AW disks at the last day of culture. Scanning electron microscopic (SEM) observations of the material surfaces after scrapping off the cell layers revealed that mineralized bone nodules remained attached to both surfaces but in larger numbers on AWa. The AWa/bone interfaces were also analyzed after fracturing the disks and by transmission electron microscopy (TEM). All these results indicated the importance of the surface composition in supporting differentiation of osteogenic cells and the subsequent apposition of bone matrix. Furthermore, prefabrication of a biological apatite layer by a biomimetic method could improve our knowledge of biomineralization processes and could find application as bone-repairing material.


Assuntos
Materiais Biomiméticos , Osso e Ossos , Fosfatase Alcalina/metabolismo , Animais , Apatitas/farmacologia , Engenharia Biomédica , Materiais Biomiméticos/metabolismo , Materiais Biomiméticos/farmacologia , Calcificação Fisiológica , Diferenciação Celular/efeitos dos fármacos , Células Cultivadas , Cerâmica/farmacologia , Microscopia Eletrônica de Varredura , Osteoblastos/citologia , Osteoblastos/metabolismo , Osteoblastos/ultraestrutura , Ratos/embriologia , Ácido Silícico/farmacologia
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