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1.
J Prosthet Dent ; 122(2): 154-159, 2019 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-31326149

RESUMO

STATEMENT OF PROBLEM: While glass ionomer cements have many unique properties and advantages, they still lack favorable mechanical properties. EQUIA Forte Fil is a newly developed glass ionomer cement (GIC) with improved mechanical strength. However, research and data on the physical properties of EQUIA Forte Fil are lacking. PURPOSE: The purpose of this in vitro study was to evaluate and compare the compressive, diametral tensile, and flexural strengths of EQUIA Forte Fil with Fuji IX GP and ChemFil Rock, restorative GICs commonly used in dentistry. Moreover, fluoride-releasing properties and surface hardness of the GICs were also assessed. MATERIAL AND METHODS: Ten disk-shaped specimens of each GIC (EQUIA Forte Fil, Fuji IX GP, and ChemFil Rock) were fabricated for mechanical and surface hardness tests by using polydimethylsiloxane (PDMS) molds. The specimens were tested after 24 hours and 7 days of immersion in distilled water at 37 °C. By using a mechanical testing machine, the compressive, diametral tensile, and flexural strengths of each GIC were measured. Fluoride-releasing properties were also evaluated (10 specimens per group). A microhardness tester was used to measure the surface hardness. The mean data were analyzed by using 1- and 2-way ANOVA (α=.05). RESULTS: EQUIA Forte Fil glass ionomer cements exhibited significantly greater (P<.05) flexural strength and surface hardness than Fuji IX GIC specimens. However, no significant difference (P>.05) was observed between the compressive and diametral tensile strength of EQUIA Forte Fil and Fuji IX GIC specimens. ChemFil Rock exhibited higher flexural strength than EQUIA Forte Fil (P>.05) but significantly lower compressive strength and microhardness (P<.05). Tested GICs matured after 1 week of immersion in distilled water, demonstrating a significant improvement in their mechanical properties. All the examined glass ionomers exhibited comparable initial fluoride-releasing properties, whereas EQUIA Forte Fil exhibited significantly higher (P<.05) amounts of fluoride release from the bulk of the material after 4 weeks. CONCLUSIONS: EQUIA Forte Fil is a promising restorative material with superior flexural strength and surface hardness compared with its predecessor, Fuji IX GP, or other commercially available glass ionomers.

2.
J Prosthet Dent ; 122(4): 348-350, 2019 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-31307804

RESUMO

A digital method for capturing the acquired emergence profile from contoured implant interim restorations is described. Three separate digital scans were made by using an intraoral scanner and aligned by using a design software program capable of merging and alignment. The Boolean Difference function was then performed by using a free software program to obtain the emergence profile. This technique may be less time-consuming than analog methods and may be more accurate than existing digital methods.

3.
J Prosthet Dent ; 2019 Jun 18.
Artigo em Inglês | MEDLINE | ID: mdl-31227233

RESUMO

STATEMENT OF PROBLEM: Screw- and cement-based retention mechanisms are used to attach prostheses to dental implants; however, each approach can lead to clinical complications such as crown fracturing or peri-implantitis. A novel abutment and prosthesis retention system has been engineered to achieve the esthetics and retention force of cement-based fixation while maintaining the retrievability of screw-retained restorations. PURPOSE: The purpose of this pilot clinical study was to evaluate the effectiveness of this innovative retention system on posterior tooth restorations. MATERIAL AND METHODS: This clinical study, with up to 6 months of follow-up, included 8 participants with posterior osseointegrated implants who met the eligibility criteria to receive the abutment and shape memory sleeve. Radiographs were used to evaluate crown seating. Crown stability was measured using the Periotest, and occlusal analysis was performed using the Tekscan system and shimstock. Peri-implant health was evaluated by probing, and the plaque and gingival indices were recorded. In addition, patient-reported outcomes were recorded. RESULTS: Minimal differences were observed between baseline and endpoint assessment of the plaque and gingival indices, probing depth, and proximal and occlusal contacts. There were no patient-reported problems or complaints about discomfort. The overall peri-implant health remained unchanged from the baseline evaluations for all participants. Proximal contact around the restoration was present at the baseline and at the conclusion of the study for 7 of the participants. Occlusal contact was observed to be either light (5 participants) or holding (3 participants). In addition, visual inspection of retrieved crowns revealed clean surfaces free of macroparticle ingress, and bacterial accumulation at the coping-abutment interface was not detected. CONCLUSIONS: The safety and efficacy findings of this pilot clinical study suggest that this new shape memory alloy-based retention system may provide a suitable alternative for implant prosthodontics. The retention system allowed for easy prosthesis seating and retrieval.

4.
J Prosthet Dent ; 2019 May 29.
Artigo em Inglês | MEDLINE | ID: mdl-31153616

RESUMO

Digital surgical planning for immediately loaded dental implants can be a predictable and accurate procedure, with the interim prosthesis also designed digitally. If the planning and execution are meticulous, chairside adjustments can be minimized because the outcome should be closely matched to the proposed digital plan. A novel dental implant abutment system made from a shape memory metal could be an answer to the cement versus screw controversy as it uses neither. This new system can provide patients with better esthetics and is biologically favorable.

5.
J Prosthet Dent ; 2019 May 09.
Artigo em Inglês | MEDLINE | ID: mdl-31079888

RESUMO

With the transition to digital workflows, moving from a digital platform to an articulator for laboratory procedures such as adding porcelain or luting titanium abutments is sometimes required. This report describes a technique to facilitate the transfer of jaw-relation records to a digital mounting template. Once digitally mounted, the casts can be printed with mounting plates attached to the temporomandibular joints in the appropriate orientation. They can then be placed in an articulator and used for layering porcelain or luting titanium abutments for screw-retained restorations.

6.
Oral Maxillofac Surg Clin North Am ; 31(3): 427-435, 2019 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-31088711

RESUMO

A case report of a complete arch interim prosthesis executed using digital work flows and with guided implant surgery is presented. The novel shape-memory retained system used to retain the complete dental prosthesis is easily indexed onto the remaining dentition, thereby being both efficient and cost-effective in the short and long term.

8.
Bioanalysis ; 10(9): 633-644, 2018 May 01.
Artigo em Inglês | MEDLINE | ID: mdl-29749254

RESUMO

AIM: Coproporphyrins (CP-I and CP-III) have been identified as possible biomarkers to predict human hepatic organic anion-transporting polypeptides-mediated-drug-interactions for a new drug entering clinical development. RESULTS: The method is applicable to quantify plasma CP-I and CP-III within 0.078-15.0 nM. The results identify and address a number of challenges encountered with porphyrin assays such as photodegradation and interferences. To overcome interferences from ubiquitous porphyrins, a surrogate matrix was used to prepare calibration standards. Quality controls were prepared in plasma and surrogate matrix to ensure parallelism between surrogate matrix and plasma. CONCLUSION: A robust UHPLC-MS/MS assay was developed and validated for CP-I and CP-III in plasma, and is currently applied to clinical studies to confirm suitability of Coproporphyrins as a potential substitute for drug-drug interaction study.


Assuntos
Biomarcadores Farmacológicos/sangue , Cromatografia Líquida de Alta Pressão/métodos , Coproporfirinas/sangue , Transportadores de Ânions Orgânicos/metabolismo , Espectrometria de Massas em Tandem/métodos , Biomarcadores Farmacológicos/química , Coproporfirinas/química , Desenho de Drogas , Interações de Medicamentos , Humanos , Transportadores de Ânions Orgânicos/química , Rifampina/sangue , Rifampina/química , Rosuvastatina Cálcica/sangue , Rosuvastatina Cálcica/química
9.
World Neurosurg ; 115: 138-142, 2018 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-29689400

RESUMO

BACKGROUND: Cases of nail gun injuries to the head and neck are rare, and treatment approach varies with each case based on location and extent of injury. CASE DESCRIPTION: We present a case of a 52-year-old male who fell off a roof holding a pneumatic nail gun and accidentally shot himself with a nail through the right frontal neck region. The nail penetrated the right sternocleidomastoid muscle and extended intracranially through the right occipital condyle with its tip embedded in the right cerebellar hemisphere. The nail coursed between the right distal cervical internal jugular vein and right internal carotid artery. There was no evidence of vascular injury on initial imaging. The barbs of the nail abutted the right sigmoid sinus, making for high risk of tear and intracranial hemorrhage on manual nail extraction. Therefore preemptive coil embolization of the right dural venous sigmoid and occipital sinuses and internal jugular bulb was performed before attempted nail removal. Using biplane fluoroscopy, orthopedic screw removal plyers were successful in snaring the head of the nail. On initial removal attempt, the head of the nail injured the distal right cervical internal carotid artery, requiring endovascular coil embolization. The nail was then successfully extracted from the neck without further immediate complications. CONCLUSION: Use of biplane fluoroscopy and preemptive endovascular embolization makes a nonsurgical approach to penetrating skull base injuries feasible. Despite improving right visual loss related to the right internal carotid artery embolization, the patient had no new focal neurologic deficits on 1-month outpatient follow-up.


Assuntos
Artéria Carótida Interna/cirurgia , Embolização Terapêutica , Veias Jugulares/cirurgia , Base do Crânio/patologia , Encéfalo/irrigação sanguínea , Encéfalo/patologia , Artéria Carótida Interna/diagnóstico por imagem , Embolização Terapêutica/métodos , Humanos , Veias Jugulares/diagnóstico por imagem , Masculino , Pessoa de Meia-Idade , Tomografia Computadorizada por Raios X/métodos
10.
J Prosthet Dent ; 120(3): 447-453, 2018 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-29703674

RESUMO

STATEMENT OF PROBLEM: Conventional approaches to adhesive bonding are not applicable to zirconia restorations. Recently, an etching solution, Zeta Etching Solution (ZES), has been introduced for etching the surface of zirconia. The effects of this etching solution on the bond strength and mechanical properties of zirconia are unknown. PURPOSE: The purpose of this in vitro study was to examine the effects of ZES on the bond strength and surface hardness of zirconia. MATERIAL AND METHODS: Two different types of partially stabilized tetragonal polycrystalline zirconia (TZP), Prettau zirconia (group P) and anterior Prettau (group AP), were evaluated with and without ZES etching. Each group was bonded to a zirconia substrate by using an adhesive resin cement. After 24 hours of storage in distilled water, the bond strength of the zirconia was analyzed. Vickers hardness was determined by using a microhardness tester. Scanning electron microscopy was used to analyze the surface microstructure and determine the mode of failure for each specimen. Results were analyzed and compared using 1-way ANOVA and Student t tests (α=.05). RESULTS: Scanning electron microscopy analysis showed that etching the surface of zirconia with ZES etching solution for 60 minutes changed the morphological characteristics and microstructure of zirconia, making the surface more irregular. The changes were more pronounced for AP specimens. Etching with ZES significantly increased the shear bond strength of zirconia (P<.05) in AP specimens. The bond strength of Prettau (P group) specimens after ZES etching did not increase significantly (P>.05). An adhesive failure mode was observed for P zirconia specimens, whereas zirconia specimens exhibited a cohesive mode of failure. No significant decrease (P>.05) was observed in the mean Vickers hardness numbers. CONCLUSIONS: Within the limitations of this in vitro study, it was concluded that etching in ZES for 30 minutes significantly enhanced the shear bond strength of highly translucent anterior Prettau (AP) zirconia restorations. Moreover, etching with ZES did not adversely affect the surface hardness of the zirconia specimens tested.

11.
J Prosthodont ; 26(8): 670-671, 2017 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-28940797

RESUMO

This clinical report describes the unusual appearance of radiopacities, lobular in nature, observed on a dental panoramic image of an edentulous patient. Upon questioning, the patient described a history of recently having hydroxylapatite-based dermal filler placed in her right and left cheeks to reduce wrinkles and enhance cosmetic appearance. The localization and shape of the radiopacities were consistent with the placement of the dermal filler.


Assuntos
Preenchedores Dérmicos , Boca Edêntula/diagnóstico por imagem , Radiografia Panorâmica , Feminino , Humanos , Pessoa de Meia-Idade
12.
J Prosthet Dent ; 118(4): 455-461, 2017 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-28385446

RESUMO

Of the available regenerative treatment options, craniofacial tissue regeneration using mesenchymal stem cells (MSCs) shows promise. The ability of stem cells to produce multiple specialized cell types along with their extensive distribution in many adult tissues have made them an attractive target for applications in tissue engineering. MSCs reside in a wide spectrum of postnatal tissue types and have been successfully isolated from orofacial tissues. These dental- or orofacial-derived MSCs possess self-renewal and multilineage differentiation capacities. The craniofacial system is composed of complex hard and soft tissues derived from sophisticated processes starting with embryonic development. Because of the complexity of the craniofacial tissues, the application of stem cells presents challenges in terms of the size, shape, and form of the engineered structures, the specialized final developed cells, and the modulation of timely blood supply while limiting inflammatory and immunological responses. The cell delivery vehicle has an important role in the in vivo performance of stem cells and could dictate the success of the regenerative therapy. Among the available hydrogel biomaterials for cell encapsulation, alginate-based hydrogels have shown promising results in biomedical applications. Alginate scaffolds encapsulating MSCs can provide a suitable microenvironment for cell viability and differentiation for tissue regeneration applications. This review aims to summarize current applications of dental-derived stem cell therapy and highlight the use of alginate-based hydrogels for applications in craniofacial tissue engineering.


Assuntos
Atitude do Pessoal de Saúde , Odontologia , Face , Células-Tronco Mesenquimais , Crânio , Engenharia Tecidual , Humanos , Boca/citologia , Regeneração , Crânio/citologia
13.
J Prosthodont ; 26(4): 339-343, 2017 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-28295831

RESUMO

PURPOSE: The decision by prosthodontic residency program directors to employ the Match process highlights the need to understand applicant priorities that influence their choice of which programs to rank highly. The purpose of this study is to determine the factors that were most important to residents when choosing from among nonmilitary based prosthodontics dental residency programs in the United States. MATERIALS AND METHODS: Following completion of a pilot study, all currently enrolled prosthodontic residents at nonmilitary residency programs were invited to participate via the internet. The study consisted of a survey instrument asking residents to rank 26 possible factors that might impact an applicant's choice of residency program. In addition, the instrument collected other possible influencing variables including gender and debt load. Mean rank scores were compared to determine the most and least important factors. Kruskal-Wallis test was used to compare specific factors between the possible influencing variables. RESULTS: Two hundred and thirty residents completed the survey instrument, representing a 54.1% response rate of possible participants. With regard to factors influencing program choice, reputation of the residency program was the factor ranked the highest by participants, followed in descending order by the program director's personality, curriculum content, access to use of the latest digital technology, and opportunities for dental implant placement. Quality of schools for children, community outreach opportunities, and the ability to moonlight were ranked as the least important factors. Male and female residents ranked factors such as tuition/stipend, curriculum content, and community outreach opportunities significantly differently. Depending on debt load, residents ranked the factors tuition/stipend, ability to moonlight, curriculum content, and safety of the area where the program is differently. CONCLUSIONS: Current prosthodontic residents valued the reputation of the program as the most important factor when applying to residency. Participant gender and debt load influence the factors chosen by residents as more or less important. These data will assist prosthodontic educators position their programs in the best possible light to attract applicants to their programs.


Assuntos
Escolha da Profissão , Internato e Residência , Prostodontia/educação , Feminino , Humanos , Masculino , Inquéritos e Questionários , Estados Unidos
14.
J Prosthet Dent ; 117(1): 8-12, 2017 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-27622784

RESUMO

An innovative abutment system has recently been developed to address the well-known limitations of screw- and cement-retained implant restorations. This abutment system offers retrievability by replacing the cement layer with a precision-engineered nickel-titanium sleeve that switches between shapes that lock and unlock the prosthesis. The avoidance of cement precludes cement-related periimplant complications, while the elimination of occlusal screw access holes may enable predictable control over occlusion and improve the structural integrity of the prosthesis. By eliminating the need for cement clean up, occlusal access closure, and occlusal adjustments after insertion, the dentist is afforded more time to attend to the patient's general needs. This paper describes the design rationale for and clinical treatment using this novel abutment system.


Assuntos
Dente Suporte , Projeto do Implante Dentário-Pivô/métodos , Técnica de Moldagem Odontológica , Prótese Dentária Fixada por Implante/métodos , Humanos , Titânio
15.
Dent Mater ; 32(10): e251-e261, 2016 10.
Artigo em Inglês | MEDLINE | ID: mdl-27520495

RESUMO

OBJECTIVE: Remineralization and demineralization are processes that compete in the oral environment. At this time, numerous therapeutic agents are being developed to promote remineralization (precipitation) or suppress demineralization (dissolution). To evaluate the relative efficacy of such treatments, there is a need for non-invasive, real-time, high-resolution quantifications of topographical changes occurring during demineralization and remineralization. METHODS: Vertical scanning interferometry (VSI) is demonstrated to be a quantitative method to assess reactions, and topographical changes occurring on enamel surfaces following exposure to demineralizing, and remineralizing liquids. RESULTS: First, the dissolution rate of enamel was compared to that of synthetic hydroxyapatite (HAP) under acidic conditions (pH=4). Second, VSI was used to compare the remineralization effects of F(-)-based and CCP-ACP agents. The former produced a remineralization rate of ≈349nm/h, similar to simulated body fluid (SBF; concentration 4.6×) while the latter produced a remineralization rate of ≈55nm/h, corresponding to 1.7× SBF. However, the precipitates formed by the CCP-ACP agent are found to demineralize 2.7× slower than that produced by its F(-)-counterpart. SIGNIFICANCE: Based on this new VSI-based data, a remineralization factor (RF) and demineralization (DF) factor benchmarked, respectively, to 1× SBF and the demineralization rate of human enamel are suggested as figures of merit of therapeutic performance of dental treatments. Taken together, the outcomes offer new insights that can inform clinicians and researchers on the selection of remineralization strategies.


Assuntos
Interferometria , Desmineralização do Dente , Remineralização Dentária , Cariostáticos , Esmalte Dentário , Humanos
16.
J Prosthodont Res ; 60(1): 20-2, 2016 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-26481058

RESUMO

PURPOSE: To recapitulate a 2003 study inquiring of US dental schools whether they teach the face bow transfer by means of a survey in order to determine if compliance with clinical evidence has improved. METHODS: The same 54 dental schools surveyed in 2003 were asked the same question regarding whether they teach the use of the face bow transfer in the complete denture curriculum. RESULTS: Teaching of the face bow transfer has increased in prevalence from 84% of surveyed schools in 2003 to 93.75% of surveyed schools in 2015. CONCLUSIONS: This finding is especially interesting in light of the fact that there is no compelling evidence supporting the use of the face bow transfer with regard to improving patient outcomes. With respect to the continued unjustified teaching of the face bow transfer, some possible reasons for non-compliance with best available evidence are presented using the medical literature for reference.


Assuntos
Planejamento de Dentadura/instrumentação , Odontologia Baseada em Evidências , Aparelhos de Tração Extrabucal , Prostodontia/educação , Aparelhos de Tração Extrabucal/estatística & dados numéricos , Humanos
17.
Am J Pharm Educ ; 77(4): S2, 2013 May 13.
Artigo em Inglês | MEDLINE | ID: mdl-23716757

RESUMO

Despite pharma's recent sea change in approach to drug discovery and development, U.S. pharmaceutical sciences graduate programs are currently maintaining traditional methods for master's and doctoral student education. The literature on graduate education in the biomedical sciences has long been advocating educating students to hone soft skills like communication and teamwork, in addition to maintaining excellent basic skills in research. However, recommendations to date have not taken into account the future trends in the pharmaceutical industry. The AACP Graduate Education Special Interest Group has completed a literature survey of the trends in the pharmaceutical industry and graduate education in order to determine whether our graduate programs are strategically positioned to prepare our graduates for successful careers in the next few decades. We recommend that our pharmaceutical sciences graduate programs take a proactive leadership role in meeting the needs of our future graduates and employers. Our graduate programs should bring to education the innovation and collaboration that our industry also requires to be successful and relevant in this century.


Assuntos
Indústria Farmacêutica/tendências , Educação de Pós-Graduação em Farmácia/tendências , Sociedades Farmacêuticas/tendências , Comportamento Cooperativo , Currículo , Difusão de Inovações , Indústria Farmacêutica/normas , Educação de Pós-Graduação em Farmácia/normas , Previsões , Guias como Assunto , Humanos , Comunicação Interdisciplinar , Relações Interinstitucionais , Liderança , Sociedades Farmacêuticas/normas
18.
J Pharm Biomed Anal ; 54(2): 368-78, 2011 Jan 25.
Artigo em Inglês | MEDLINE | ID: mdl-20926216

RESUMO

The work described in this paper involves development of a high-throughput on-line microfluidic sample extraction method using capillary micro-columns packed with MIP beads coupled with tandem mass spectrometry for the analysis of urinary NNAL. The method was optimized and matrix effects were evaluated and resolved. The method enabled low sample volume (200 µL) and rapid analysis of urinary NNAL by direct injection onto the microfluidic column packed with molecularly imprinted beads engineered to NNAL. The method was validated according to the FDA bioanalytical method validation guidance. The dynamic range extended from 20.0 to 2500.0 pg/mL with a percent relative error of ±5.9% and a run time of 7.00 min. The lower limit of quantitation was 20.0 pg/mL. The method was used for the analysis of NNAL and NNAL-Gluc concentrations in smokers' urine.


Assuntos
Butanóis/urina , Glucuronatos/urina , Nitrosaminas/urina , Polímeros/química , Piridinas/urina , Espectrometria de Massas em Tandem/métodos , Adulto , Calibragem , Cromatografia Líquida/métodos , Feminino , Humanos , Masculino , Microfluídica/métodos , Pessoa de Meia-Idade , Impressão Molecular , Estrutura Molecular , Peso Molecular , Sistemas On-Line , Controle de Qualidade , Padrões de Referência , Reprodutibilidade dos Testes , Fatores de Tempo
19.
Crit Rev Toxicol ; 40(4): 305-27, 2010 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-20210694

RESUMO

Tobacco use constitutes a leading cause of mortality and morbidity worldwide. Tobacco-specific nitrosamines (TSNAs) are an important class of biomarkers for tobacco carcinogen uptake. The current review focuses on the issues and developments in analysis of these compounds in human biological matrices. The two most widely used techniques for TSNA bioanalysis are gas chromatography coupled with thermal energy analysis and liquid chromatography coupled with mass spectrometry, employing various sample preparation techniques. The review provides an overview of the tools and techniques currently available for TSNA bioanalysis that will help towards the ultimate goal of understanding the mechanisms of cancer caused by the use of tobacco products. A contrast and comparison of the important aspects of bioanalysis such as sample preparation, compound detection, and throughput is discussed for the thermal energy analysis- and mass spectrometry-based techniques. Complex sample extraction procedures, throughput, and the ability to validate are important issues of concern for the gas chromatography-thermal energy analysis-based methods. On the other hand, addressing ion suppression matrix effects remains an important challenge for hyphenated mass spectrometry-based methods. The review also provides an extensive summary of analytical procedures for various studies measuring tobacco-specific nitrosamines in different biological matrices.


Assuntos
Cromatografia Gasosa/métodos , Cromatografia Líquida/métodos , Espectrometria de Massas/métodos , Nitrosaminas/análise , Tabaco/química , Técnicas de Laboratório Clínico , Humanos , Neoplasias/etiologia , Nicotina/análise , Nitrosaminas/química , Pesquisa , Fumar , Tabaco sem Fumaça/análise
20.
Pharm Res ; 27(5): 786-95, 2010 May.
Artigo em Inglês | MEDLINE | ID: mdl-20229134

RESUMO

PURPOSE: To develop a unique in vitro aqueous fluid-capacity-limited dissolution system for the kinetic assessment of respirable aerosol drug particles from inhaler products. METHODS: Aerosol particles of 5 inhaled corticosteroids (ICSs) from 7 inhaler products were collected in the aerodynamic 2.1-3.3 or 4.7-5.8 mum on the filter membranes using the Andersen cascade impactor. Each filter membrane was then placed onto the donor compartment of the Transwell(R) system, where addition of 0.04ml aqueous fluid initiated aerosol ICS dissolution and permeation across its supporting membrane at 37 degrees C and approximately 100% humidity. RESULTS: The % profiles of dissolution and permeation were apparent first-order or pseudo-zero-order, reaching varying 1.9-95.0% by 5 h. Their kinetics overall conformed to the ICS aqueous solubility. With increasing aerosol mass, however, the profiles decelerated, attributed to undissolved ICSs left by the limited dissolution fluid capacity. The profiles could be also product-specific, as beclomethasone dipropionate aerosols from QVAR dissolved faster than those from VANCERIL, whereas fluticasone propionate aerosols from two different inhaler products exhibited comparable profiles. The 2.1-3.3 mum aerosols dissolved faster than the 4.7-5.8 mum aerosols. CONCLUSIONS: Aerosol ICS dissolution into the limited aqueous fluid volume differed kinetically due to ICS solubility and aerosol mass, size, formulation and/or generation.


Assuntos
Aerossóis/química , Preparações Farmacêuticas/administração & dosagem , Administração por Inalação , Corticosteroides/administração & dosagem , Corticosteroides/química , Química Farmacêutica , Filtração , Cinética , Membranas Artificiais , Nebulizadores e Vaporizadores , Tamanho da Partícula , Permeabilidade , Preparações Farmacêuticas/química , Solubilidade , Soluções , Água
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