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1.
J Clin Periodontol ; 47(7): 788-795, 2020 07.
Artículo en Inglés | MEDLINE | ID: mdl-32390194

RESUMEN

OBJECTIVES: The purpose of this study was to investigate the association between impaired pulmonary function and periodontitis. MATERIALS AND METHODS: From the Third National Health and Nutrition Examination Survey data, we examined the association between pulmonary function and severity of periodontitis using the univariate and multivariate regression models. Moreover, the association between obstructive or restrictive spirometry patterns and periodontitis status was also determined by multivariable logistic regression analysis. RESULTS: A total of 10,645 participants were included in our study. The values of predicted FEV1%, predicted FVC%, and FEV1/FVC were found to gradually decline with increasing severity of periodontitis (p < .001). Obstructive and restrictive pulmonary functions were significantly associated with severity of periodontitis. CONCLUSION: Individuals with a greater degree of periodontitis had poor pulmonary function. However, further long-term cohort studies are required for a comprehensive evaluation.


Asunto(s)
Enfermedades Pulmonares , Periodontitis , Volumen Espiratorio Forzado , Humanos , Pulmón , Encuestas Nutricionales , Periodontitis/complicaciones , Periodontitis/epidemiología , Espirometría
2.
J Formos Med Assoc ; 119(1 Pt 2): 282-289, 2020 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-31208826

RESUMEN

BACKGROUND/PURPOSE: The objective of this 2-arm parallel trial was to test the superiority of self-ligating brackets (SLB) over conventional brackets (CB) in terms of perceived pain for orthodontic patients. METHODS: Patients about to undergo treatment were included to fixed appliance placed with CB or SLB. Eligibility criteria included malocclusion patients whose age between 12 to 40 years and suitable for orthodontic fixed appliance treatment. The main outcome was pain intensity measured by visual analog scale (VAS) with all patients followed at 4 h, 24 h, 3 days, 1 week and 1 month. Randomization was accomplished with a computer-generated list of random numbers. Blinding was applicable for outcome assessment only. Data were analyzed using multi-level nonlinear mixed effect model, Friedman's test and Wilcoxon signed rank test with the Bonferroni correction for multiple tests. RESULTS: Eight-eight patients were randomized in a 1:1 ratio to either SLB or CB. All patients completed the study, and none were lost to follow-up. There were no drop-outs after randomization. Baseline characteristics were similar between groups. The is no statistical significant difference in pain intensity between CB and SLB at 4 h, 24 h, 3 days, 1 week and 1 month. Data were analyzed on an intention-to-treat basis. No serious harm was observed. CONCLUSION: The results of this study indicated no evidence that the pain intensity differs between CB and SLB at 4 h, 24 h, 3 days, 1 week and 1 month.


Asunto(s)
Diseño de Aparato Ortodóncico , Soportes Ortodóncicos , Alambres para Ortodoncia , Dolor/etiología , Adolescente , Adulto , Niño , Femenino , Humanos , Masculino , Maloclusión/terapia , Dimensión del Dolor , Factores de Tiempo , Adulto Joven
3.
Am J Orthod Dentofacial Orthop ; 155(4): 584-591, 2019 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-30935613

RESUMEN

Surgical interventions on the alveolar ridges aimed at facilitating orthodontic tooth movement have been extensively reported. However, unexpected events or complications still occur in daily practice. The purpose of this report was to present a novel 3-dimensional (3D) computer-assisted piezocision guide (CAPG) designed to be translucent for increased visibility, rigid for enhanced support during guidance, and porous for profuse irrigation during procedure. Such a design can function to minimize the risk of surgical complications. In this case, we present a novel 3D-printed CAPG to facilitate a minimally invasive periodontal accelerated osteogenic orthodontics (PAOO) procedure with a guide that provides accuracy, adequate visibility, and greater access for the coolant to reach the surgery site. By navigating the cone-beam computed tomography data, we precisely know the cortical bone thickness, root direction, and interrelations between anatomic structures in an individual situation, which allows us to design our cutting slot for the required length and depth according to the operator's knowledge. Finally, 3D printing was applied, transferring our surgical plan to fabricate the CAPG. Moreover, the well designed pores on the CAPG allow effective irrigation during the piezocision procedure. This minimally invasive procedure was uneventful, and no devitalized tooth or alveolar bone was found.


Asunto(s)
Procedimientos Quirúrgicos Ortognáticos/métodos , Piezocirugía/métodos , Impresión Tridimensional , Proceso Alveolar/cirugía , Femenino , Humanos , Maloclusión Clase I de Angle/cirugía , Persona de Mediana Edad , Ortodoncia Correctiva/métodos
4.
Am J Infect Control ; 2024 Jan 30.
Artículo en Inglés | MEDLINE | ID: mdl-38301898

RESUMEN

BACKGROUND: This prospective study aimed to explore the effectiveness of an oral care intervention with Tegaderm on the oral mucosal health of intubated patients. METHODS: A total of 70 intubated patients were included and randomly assigned to 1 of 3 groups, clean water brushing teeth (n = 23), brushing teeth combined with mouthwash (BTM) (n = 23), and brushing teeth combined with mouthwash and Tegaderm (BTMT) (n = 24). The Oral Mucositis Assessment Scale (OMAS) was applied to evaluate the patient's oral mucosal health before and after oral care intervention. RESULTS: The BTMT group had lower OMAS scores in almost all regions of the oral cavity, compared to the brushing teeth and BTM groups. The general linear model for repeated measurement indicated the BTMT group had the lowest total OMAS scores from Day 2 to Day 4 after the initiation of baseline OMAS evaluation. Of the 3 intervention groups, the BTMT group had the shortest length of endotracheal intubation. The BTMT group had the lowest incidence rate of ventilator-associated pneumonia; however, no significant between-group differences were found. CONCLUSIONS: BTMT effectively reduced the decline in oral mucosal health that was caused by endotracheal intubation and shortened the length of endotracheal intubation.

5.
Children (Basel) ; 9(7)2022 Jul 18.
Artículo en Inglés | MEDLINE | ID: mdl-35884057

RESUMEN

We conducted this retrospective study to identify potential clinical, polysomnographic, and cephalometric predictors for the treatment outcomes of a tongue-beaded oral appliance (OA) in children with obstructive sleep apnea syndrome (OSAS). In total, 63 patients­50 boys and 13 girls ranging in age from 4 to 16 years­underwent OA treatment nightly for at least 6 months. A baseline digital lateral cephalometric radiograph was obtained for each patient. Multivariate logistic regression analysis was performed to examine predictors for the treatment outcome based on the clinical and cephalometric measurements. Overall, 28 patients responded to the treatment (post-treatment improvement > 50% or apnea−hypopnea index (AHI) < 1/h), and 35 did not (post-treatment improvement < 50% and AHI ≥ 1/h). Significantly larger cranial base angle (SNBa), smaller lower gonial angle (LGo Angle), and shorter length of anterior cranial base (SN) were found in responders. Smaller lower gonial angle (LGo Angle) and smaller anterior cranial base (SN) predict a favorable outcome for pediatric OSAS using a tongue-beaded OA. This finding will equip practitioners with additional insights when selecting suitable candidates for OA therapy in pediatric patients.

6.
J Dent Sci ; 13(3): 263-266, 2018 Sep.
Artículo en Inglés | MEDLINE | ID: mdl-30895130

RESUMEN

BACKGROUND/PURPOSE: It was found that body temperature would be gradually increased during pediatric full mouth rehabilitation surgery. Although the etiology is unknown, here, we introduced an effective method to maintain normothermia during this kind of surgery. MATERIALS AND METHODS: Following IRB approval, the medical records of pediatric patients who received full mouth rehabilitation surgery from Jan. 2014 through Jun. 2016 were collected. All the patients included were managed by a "tent-like draping" with a forced-air warmer (Life-Air 1000, Progressive Dynamics Inc.). The temperature of the forced-air was changed from 38 °C to cool ambient temperature when the body temperature higher than 36 °C. The body temperatures (preoperative, periodic during operation, and postoperative) and the maximum body temperature changes during operation were recorded. The data was compared with the results of a previous report. RESULTS: Total 37 patients were enrolled. The maximum temperature change during operation was 2.08 ± 0.6 °C. The incidence of body temperature higher than 37.5 °C during operation was 10.8% (4/37). Compare to the previous report in which the patients received the same operation with ordinary surgical draping, the maximum temperature change and the incidence of body temperature higher than 37.5 °C during operation were significantly lower in patients received "tent-like draping" (2.08 ± 0.64 °C vs 2.50 ± 1.17 °C, p < 0.001; and 10.8% (4/37) vs 32.4% (11/34), p < 0.05, respectively). CONCLUSION: The increase of body temperature during pediatric full mouth rehabilitation surgery can be effectively controlled by ambient forced-air cooling using tent-like draping.

7.
Arch Oral Biol ; 90: 19-26, 2018 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-29524788

RESUMEN

OBJECTIVE: Homeostasis of intracellular pH (pHi) plays vital roles in many cell functions, such as proliferation, apoptosis, differentiation and metastasis. Thus far, Na+-H+ exchanger (NHE), Na+-HCO3- co-transporter (NBC), Cl-/HCO3- exchanger (AE) and Cl-/OH- exchanger (CHE) have been identified to co-regulate pHi homeostasis. However, functional and biological pHi-regulators in human dental pulp stem cells (hDPSCs) have yet to be identified. DESIGN: Microspectrofluorimetry technique with pH-sensitive fluorescent dye, BCECF, was used to detect pHi changes. NH4Cl and Na+-acetate pre-pulse were used to induce intracellular acidosis and alkalosis, respectively. Isoforms of pHi-regulators were detected by Western blot technique. RESULTS: The resting pHi was no significant difference between that in HEPES-buffered (nominal HCO3--free) solution or CO2/HCO3-buffered system (7.42 and 7.46, respectively). The pHi recovery following the induced-intracellular acidosis was blocked completely by removing [Na+]o, while only slowed (-63%) by adding HOE694 (a NHE1 specific inhibitor) in HEPES-buffered solution. The pHi recovery was inhibited entirely by removing [Na+]o, while adding HOE 694 pulse DIDS (an anion-transporter inhibitor) only slowed (-55%) the acid extrusion. Both in HEPES-buffered and CO2/HCO3-buffered system solution, the pHi recovery after induced-intracellular alkalosis was entirely blocked by removing [Cl-]o. Western blot analysis showed the isoforms of pHi regulators, including NHE1/2, NBCe1/n1, AE1/2/3/4 and CHE in the hDPSCs. CONCLUSIONS: We demonstrate for the first time that resting pHi is significantly higher than 7.2 and meditates functionally by two Na+-dependent acid extruders (NHE and NBC), two Cl--dependent acid loaders (CHE and AE) and one Na+-independent acid extruder(s) in hDPSCs. These findings provide novel insight for basic and clinical treatment of dentistry.


Asunto(s)
Equilibrio Ácido-Base/fisiología , Citoplasma/metabolismo , Pulpa Dental/metabolismo , Homeostasis/fisiología , Células Madre/metabolismo , Desequilibrio Ácido-Base , Ácidos/farmacología , Cloruro de Amonio , Antiportadores/metabolismo , Apoptosis , Tampones (Química) , Diferenciación Celular , Proliferación Celular , Citoplasma/efectos de los fármacos , Guanidinas/farmacología , Humanos , Concentración de Iones de Hidrógeno , Bombas Iónicas/efectos de los fármacos , Bombas Iónicas/metabolismo , Metástasis de la Neoplasia , Isoformas de Proteínas , Sodio/farmacología , Simportadores de Sodio-Bicarbonato/metabolismo , Intercambiador 1 de Sodio-Hidrógeno/metabolismo , Intercambiadores de Sodio-Hidrógeno/metabolismo , Células Madre/efectos de los fármacos , Sulfonas/farmacología
8.
J Periodontol ; 78(6): 1120-8, 2007 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-17539727

RESUMEN

BACKGROUND: Porphyromonas gingivalis is recognized as one of the major periodontal pathogens in chronic periodontitis, a common infectious disease characterized by inflammation and destruction of periodontal tissues. Several animal models with P. gingivalis have been used in periodontitis studies. Additionally, multiple approaches have also been applied to measuring alveolar bone loss in periodontitis models, including histomorphometry, morphometry, and radiography. The aims of this study were to assess periodontal inflammatory lesions after P. gingivalis-induced periodontitis and use this model to compare three approaches for assessing alveolar bone loss. METHODS: Twelve-week-old male C57BL/6 mice were divided into two groups: 48 P. gingivalis-infected and 52 untreated control mice. Periodontitis was induced by wrapping P. gingivalis-soaked ligatures around the left maxillary second molar and changing the ligatures every other day. Mice were euthanized on days 0, 3, 7, and 10 after ligature placement, for a total of 12 experimental and 13 control mice per time point. Epithelial downgrowth, inflammation, and osteoclast activity were evaluated; alveolar bone loss was determined by histomorphometry, morphometry, and microcomputed tomography. RESULTS: The P. gingivalis-infected group showed significantly increased epithelial downgrowth (P <0.05), inflammation (P <0.05), alveolar bone loss (P <0.05), and osteoclast activity (P <0.05) throughout the experimental period compared to the controls. All three methods yielded efficient evaluation of alveolar bone loss. CONCLUSIONS: Our results show evidence that the P. gingivalis-soaked ligature-induced murine model mounts an adequate inflammatory response and exhibits periodontal tissue breakdown compatible with other models of periodontal disease. In addition, alveolar bone loss can accurately be quantified using any of the three alveolar bone analyses presented in this article.


Asunto(s)
Pérdida de Hueso Alveolar/patología , Proceso Alveolar/patología , Enfermedades Maxilares/patología , Porphyromonas gingivalis/aislamiento & purificación , Pérdida de Hueso Alveolar/microbiología , Proceso Alveolar/microbiología , Animales , Placa Dental/microbiología , Epitelio/crecimiento & desarrollo , Masculino , Enfermedades Maxilares/microbiología , Ratones , Microcomputadores , Modelos Animales , Osteoclastos/enzimología , Periodontitis/microbiología , Periodontitis/patología , Tomografía Computarizada por Rayos X/métodos
9.
PLoS One ; 12(7): e0182370, 2017.
Artículo en Inglés | MEDLINE | ID: mdl-28759627

RESUMEN

Allergic rhinitis (AR) is associated with various developmental issues that affecting dentition. We aimed to determine whether AR is associated with an increased risk of traumatic dental injuries (TDIs) in Taiwanese individuals. We used the Taiwan National Health Insurance Research Database (NHIRD) to conduct a nested case-control study. We compared an AR cohort with a matched cohort of patients without AR. New TDI cases were determined during our study period. To compare TDI risk between our study cohorts, we used Cox proportional regression analysis, and hazard ratios (HR) with 95% confidence intervals (CI) were calculated to quantify the association between AR exposure and TDI risk. In total, 76749 patients with AR (31715 male; 45034 female) were identified. In the AR and the non-AR cohorts, 312 patients in total had TDI. Patients with AR had a significantly higher risk of TDI than those without AR (aHR = 1.92; 95% CI = 1.459-2.525; P < 0.001). The risk of TDI was markedly higher in the AR cohort, except in the 3-12-year-old group, and with a CCI ≥ 1. AR patients had a future risk of TDI, indicating a potentially linked disease pathophysiology. The association between AR and TDI is greater among general patients. Clinicians and caregivers should be aware of potential TDI co-morbidity in patients with AR.


Asunto(s)
Rinitis Alérgica/epidemiología , Traumatismos de los Dientes/epidemiología , Adolescente , Adulto , Estudios de Casos y Controles , Niño , Preescolar , Femenino , Humanos , Masculino , Persona de Mediana Edad , Taiwán
10.
Sci Rep ; 6: 33581, 2016 09 20.
Artículo en Inglés | MEDLINE | ID: mdl-27645567

RESUMEN

Cephalometric tracing is a standard analysis tool for orthodontic diagnosis and treatment planning. The aim of this study was to develop and validate a fully automatic landmark annotation (FALA) system for finding cephalometric landmarks in lateral cephalograms and its application to the classification of skeletal malformations. Digital cephalograms of 400 subjects (age range: 7-76 years) were available. All cephalograms had been manually traced by two experienced orthodontists with 19 cephalometric landmarks, and eight clinical parameters had been calculated for each subject. A FALA system to locate the 19 landmarks in lateral cephalograms was developed. The system was evaluated via comparison to the manual tracings, and the automatically located landmarks were used for classification of the clinical parameters. The system achieved an average point-to-point error of 1.2 mm, and 84.7% of landmarks were located within the clinically accepted precision range of 2.0 mm. The automatic landmark localisation performance was within the inter-observer variability between two clinical experts. The automatic classification achieved an average classification accuracy of 83.4% which was comparable to an experienced orthodontist. The FALA system rapidly and accurately locates and analyses cephalometric landmarks in lateral cephalograms, and has the potential to significantly improve the clinical work flow in orthodontic treatment.


Asunto(s)
Cefalometría/métodos , Cefalometría/normas , Cabeza/anatomía & histología , Cabeza/diagnóstico por imagen , Procesamiento de Imagen Asistido por Computador , Adolescente , Adulto , Anciano , Automatización , Niño , Curaduría de Datos , Femenino , Cabeza/anomalías , Humanos , Interpretación de Imagen Asistida por Computador , Procesamiento de Imagen Asistido por Computador/métodos , Procesamiento de Imagen Asistido por Computador/normas , Masculino , Persona de Mediana Edad , Vigilancia en Salud Pública , Radiografía/métodos , Radiografía/normas , Reproducibilidad de los Resultados , Adulto Joven
12.
J Dent Sci ; 11(2): 189-195, 2016 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-30894970

RESUMEN

BACKGROUND/PURPOSE: Most mandibular first molars have two roots. A major common variation of this tooth is the presence of a distolingual root, which is a common Mongoloid trait in certain populations. The aim of this article was to examine crown morphology in relation to the presence of the distolingual root. MATERIALS AND METHODS: Using dental casts, the crown morphology of 141 mandibular first molars from 71 Taiwanese individuals was analyzed. Periapical radiographs were used to detect distolingual roots. The length and width of the crowns and the crown units (i.e., trigonid and talonid) were measured. Ten intercuspal distances and five cusp angles were examined. RESULTS: The buccolingual dimension of the crown and its ratio to the mesiodistal dimension were significantly increased in molars with a distolingual root, compared to molars without a distolingual root. Mesiodistal crown dimensions were similar; however, the crown unit dimensions were different: molars with a distolingual root had a shorter mesiodistal trigonid dimension but a longer talonid dimension, compared to molars without a distolingual root. The intercuspal distances from the three buccal cusps to the distolingual cusp were significantly longer, however, the distance between the mesiobuccal cusp and mesiolingual cusp was significantly shorter in teeth with a distolingual root than in teeth without a distolingual root. A significantly wider mesiolingual angle and narrower distolingual angle were observed in molars with a distolingual root, compared to molars without a distolingual root. CONCLUSION: The presence of a distolingual root significantly increased the buccolingual dimension of the crown and the location of distolingual cusp is significantly closer to the lingual side.

13.
Med Image Anal ; 31: 63-76, 2016 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-26974042

RESUMEN

Dental radiography plays an important role in clinical diagnosis, treatment and surgery. In recent years, efforts have been made on developing computerized dental X-ray image analysis systems for clinical usages. A novel framework for objective evaluation of automatic dental radiography analysis algorithms has been established under the auspices of the IEEE International Symposium on Biomedical Imaging 2015 Bitewing Radiography Caries Detection Challenge and Cephalometric X-ray Image Analysis Challenge. In this article, we present the datasets, methods and results of the challenge and lay down the principles for future uses of this benchmark. The main contributions of the challenge include the creation of the dental anatomy data repository of bitewing radiographs, the creation of the anatomical abnormality classification data repository of cephalometric radiographs, and the definition of objective quantitative evaluation for comparison and ranking of the algorithms. With this benchmark, seven automatic methods for analysing cephalometric X-ray image and two automatic methods for detecting bitewing radiography caries have been compared, and detailed quantitative evaluation results are presented in this paper. Based on the quantitative evaluation results, we believe automatic dental radiography analysis is still a challenging and unsolved problem. The datasets and the evaluation software will be made available to the research community, further encouraging future developments in this field. (http://www-o.ntust.edu.tw/~cweiwang/ISBI2015/).


Asunto(s)
Algoritmos , Benchmarking/métodos , Benchmarking/normas , Interpretación de Imagen Radiográfica Asistida por Computador/métodos , Radiografía Dental/métodos , Radiografía Dental/normas , Cefalometría/normas , Humanos , Intensificación de Imagen Radiográfica/normas , Interpretación de Imagen Radiográfica Asistida por Computador/normas , Radiografía de Mordida Lateral/normas , Reproducibilidad de los Resultados , Sensibilidad y Especificidad , Taiwán
14.
Ann Biomed Eng ; 43(4): 1024-35, 2015 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-25331100

RESUMEN

In this study, cell-material adhesive strength and cellular mechanical properties were measured using atomic force microscopy (AFM) to track cell attachment and osteogenic differentiation. First, chitosan substrates were treated with simulated body fluid (SBF) for various periods, resulting in substrates with different osteoconductivity. The X-ray diffraction (XRD), energy-dispersive X-ray spectroscopy (EDS) and in vitro tests revealed that the biomimeticity and osteoconductivity of substrates increased with increasing time of SBF treatment. When the SBF immersion exceeded 14 days, the chitosan substrates exhibited their highest biocompatibility and osteoconductivity. AFM measurements indicated specifically high adhesive forces between SBF-treated chitosan and osteogenic cells, causing better cell attachment. The results demonstrate that cell adhesion was controlled by cell-material adhesive strength, which were in turn controlled via the SBF treatment time. The adhesive strength between cells and material also accounted for the chitosan substrates' specific selectivity toward osteogenic cells. A two-step increase in mechanical strength was observed for the nucleus and cytoplasm of osteogenic cells. The results indicate that through the use of AFM, the real-time cell-material interforce and cellular mechanics can be identified. The adhesive strength was positively correlated to the cell attachment, and the second increase in the Young's modulus of nucleus and cytoplasm was correlated to early osteogenic differentiation.


Asunto(s)
Materiales Biomiméticos/química , Regeneración Ósea , Quitosano/química , Durapatita/química , Ensayo de Materiales , Microscopía de Fuerza Atómica , Animales , Diferenciación Celular , Línea Celular Tumoral , Humanos , Ratones , Osteogénesis , Propiedades de Superficie
15.
IEEE Trans Med Imaging ; 34(9): 1890-900, 2015 Sep.
Artículo en Inglés | MEDLINE | ID: mdl-25794388

RESUMEN

Cephalometric analysis is an essential clinical and research tool in orthodontics for the orthodontic analysis and treatment planning. This paper presents the evaluation of the methods submitted to the Automatic Cephalometric X-Ray Landmark Detection Challenge, held at the IEEE International Symposium on Biomedical Imaging 2014 with an on-site competition. The challenge was set to explore and compare automatic landmark detection methods in application to cephalometric X-ray images. Methods were evaluated on a common database including cephalograms of 300 patients aged six to 60 years, collected from the Dental Department, Tri-Service General Hospital, Taiwan, and manually marked anatomical landmarks as the ground truth data, generated by two experienced medical doctors. Quantitative evaluation was performed to compare the results of a representative selection of current methods submitted to the challenge. Experimental results show that three methods are able to achieve detection rates greater than 80% using the 4 mm precision range, but only one method achieves a detection rate greater than 70% using the 2 mm precision range, which is the acceptable precision range in clinical practice. The study provides insights into the performance of different landmark detection approaches under real-world conditions and highlights achievements and limitations of current image analysis techniques.


Asunto(s)
Puntos Anatómicos de Referencia/diagnóstico por imagen , Cefalometría/métodos , Cabeza/diagnóstico por imagen , Procesamiento de Imagen Asistido por Computador/métodos , Adolescente , Adulto , Niño , Cabeza/anatomía & histología , Humanos , Persona de Mediana Edad , Radiografía Dental , Adulto Joven
16.
Colloids Surf B Biointerfaces ; 115: 1-7, 2014 Mar 01.
Artículo en Inglés | MEDLINE | ID: mdl-24317428

RESUMEN

Ozone oxidation can easily produce peroxides containing active free radicals that can be used for the surface modification of biomaterials. This process is highly efficient and nontoxic. In this research, naringin, an HMG-CoA reductase inhibitor that can promote bone formation, was immobilized onto a chitosan film using ozone activation. First, a chitosan film was treated by ozone to produce peroxides; these peroxides were then quantified and their amount was optimized by an iodide assay. For the in vitro delivery of naringin, a chitosan-naringin substrate was immersed in phosphate-buffered saline to quantify the released amount of naringin. It was found that the immobilized naringin was slowly released over the course of two weeks, where its concentration in the medium was controlled by this delivery process. The results of cell culture showed that cell viability and early osteogenic differentiation, as measured by alkaline phosphatase expression, were promoted with the immobilized naringin on chitosan substrates. The expression of osteogenic proteins, including type-I collagen, bone siloprotein, and osteocalcin, were also enhanced. According to the results of Smad1 and Smad6 phosphorylation, immobilized naringin on ozonated chitosan substrates would be able to initiate bone morphogenetic protein-Smad signaling by activating receptor Smad and by suppressing inhibitory Smad. The results in this research demonstrated that the naringin-chitosan substrate produced by biocompatible ozone activation was highly osteoconductive without cytotoxicity.


Asunto(s)
Quitosano/química , Flavanonas/farmacología , Ozono/farmacología , Ingeniería de Tejidos/métodos , Fosfatasa Alcalina/metabolismo , Animales , Diferenciación Celular/efectos de los fármacos , Supervivencia Celular/efectos de los fármacos , Células Cultivadas , Colágeno Tipo I/metabolismo , Sialoproteína de Unión a Integrina/metabolismo , Osteocalcina/metabolismo , Osteogénesis/efectos de los fármacos , Peróxidos/análisis , Fosforilación/efectos de los fármacos , Ratas , Proteínas Smad/metabolismo , Espectrofotometría Infrarroja
17.
ACS Chem Neurosci ; 4(8): 1229-35, 2013 Aug 21.
Artículo en Inglés | MEDLINE | ID: mdl-23705903

RESUMEN

Engineering the cellular microenvironment has great potential to create a platform technology toward engineering of tissue and organs. This study aims to engineer a neural microenvironment through fabrication of three-dimensional (3D) engineered collagen matrixes mimicking in-vivo-like conditions. Collagen was chemically modified with a pentapeptide epitope consisting of isoleucine-lysine-valine-alanine-valine (IKVAV) to mimic laminin structure supports of the neural extracellular matrix (ECM). Three-dimensional collagen matrixes with and without IKVAV peptide modification were fabricated by freeze-drying technology and chemical cross-linking with glutaraldehyde. Structural information of 3D collagen matrixes indicated interconnected pores structure with an average pore size of 180 µm. Our results indicated that culture of dorsal root ganglion (DRG) cells in 3D collagen matrix was greatly influenced by 3D culture method and significantly enhanced with engineered collagen matrix conjugated with IKVAV peptide. It may be concluded that an appropriate 3D culture of neurons enables DRG to positively improve the cellular fate toward further acceleration in tissue regeneration.


Asunto(s)
Colágeno/química , Matriz Extracelular/química , Ganglios Espinales/química , Laminina/química , Neuronas/química , Fragmentos de Péptidos/química , Animales , Técnicas de Cultivo de Célula/métodos , Hipoxantina Fosforribosiltransferasa/metabolismo , Proteínas Asociadas a Microtúbulos/metabolismo , Nestina/metabolismo , Reacción en Cadena en Tiempo Real de la Polimerasa , Porcinos , Ingeniería de Tejidos/métodos
18.
Biomed Mater ; 5(5): 054117, 2010 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-20876961

RESUMEN

Chitosan, a biocompatible material that has been widely used in bone tissue engineering, is believed to have a high affinity to osteoblastic cells. This research is the first to prove this hypothesis. By using atomic force microscopy (AFM) with a chitosan-modified cantilever, quantitative evaluation of the interforce between chitosan and cells was carried out. A chitosan tip functionalized with Arg-Gly-Asp (RGD) was also used to measure the interforce between RGD-chitosan and osteoblastic cells. This research concluded by examining cell adhesion and spreading of chitosan substrates as further characterization of the interactions between cells and chitosan. The force measured by AFM showed that the interforce between chitosan and osteoblasts was the highest (209 nN). The smallest adhesion force (61.8 nN) appeared between chitosan and muscle fibroblasts, which did not demonstrate any osteoblastic properties. This result proved that there was a significant interaction between chitosan and bone cells, and correlated with the observations of cell attachment and spreading. The technique developed in this research directly quantified the adhesion between chitosan and cells. This is the first study to demonstrate that specific interaction exists between chitosan and osteoblasts.


Asunto(s)
Materiales Biocompatibles/metabolismo , Quitosano/metabolismo , Microscopía de Fuerza Atómica/métodos , Osteoblastos/citología , Materiales Biocompatibles/química , Adhesión Celular , Células Cultivadas , Quitosano/química , Fibroblastos/citología , Fibroblastos/metabolismo , Humanos , Oligopéptidos/química , Osteoblastos/metabolismo , Osteoblastos/fisiología , Osteoblastos/ultraestructura , Osteocitos/metabolismo , Ingeniería de Tejidos/métodos
19.
Am J Orthod Dentofacial Orthop ; 125(1): 65-70, 2004 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-14718881

RESUMEN

To determine the influence of various bracket base designs on bond strength and debond interface, 6 types of metal interlock brackets of different sizes and with different base designs were evaluated. The bracket base types and mesh sizes tested were as follows: retention groove base (Dynalock, Unitek, Monrovia, Calif), circular concave base (Accuarch appliance Formula-R, Tomy, Tokyo, Japan), double mesh with 5.1 x 10(-2) mm2 mesh size (Ultratrimm, Dentaurum, Ispringen, Germany), double mesh, 3.1 x 10(-2) mm2 (Minidiagonali Roth, Leone, Florence, Italy), double mesh, 3.1 x 10(-2) mm2 (Tip-edge Rx-I, TP Orthodontics, LaPorte Ind), and double mesh, 2.9 x 10(-2) mm2 (Mini Diamond, Ormco, Glendora, Calif). The Unitek bracket is cast in 1 piece; the other brackets are welded together. Brackets were bonded to human teeth and then debonded on a testing machine. The debond interface was recorded and analyzed with scanning electron microscopy and energy-dispersive x-ray spectrometry, and the distribution of interfaces was determined. The ranking of bond strength of individual bases (kg/base) from highest to lowest was Tomy, Dentaurum, Unitek, Leone, TP Orthodontics, and Ormco. The ranking of bonding strength per area squared MPa from highest to lowest was Tomy, Dentaurum, Leone, Unitek, TP Orthodontics, and Ormco. Debond in interfaces occurred between the bracket and resin, within the resin, or between the resin and enamel. The most debonded interfaces were between the bracket and resin and between the resin and enamel. The Tomy bracket, with its circular concave base, produced greater bond strength than did the mesh-based brackets; among the mesh-based brackets, Dentaurum, with the larger mesh size, produced greater bond strength than the brackets with smaller mesh sizes. The Unitek bracket, with its 1-piece cast base with retention grooves, ranked in the midrange of bond strength.


Asunto(s)
Recubrimiento Dental Adhesivo/normas , Análisis del Estrés Dental , Diseño de Aparato Ortodóncico , Soportes Ortodóncicos , Análisis de Varianza , Desconsolidación Dental , Ensayo de Materiales , Propiedades de Superficie
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