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1.
J Clin Orthod ; 57(5): 291-297, 2023 May.
Artigo em Inglês | MEDLINE | ID: mdl-37317540
2.
Ultrason Sonochem ; 92: 106261, 2023 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-36516722

RESUMO

One of the earliest and most prevalent processing methods to increase the shelf-life of foods is drying. In recent years, there has been an increased demand to improve product quality while lowering processing times, expenses, and energy usage in the drying process. Pre-treatments are therefore effectively used before drying to enhance heat and mass transfer, increase drying efficiency, and lessen degradation of final product quality. When food is dried, changes are expected in its taste, color, texture, and physical, chemical, and microbial properties. This has led to the need for research and development into the creation of new and effective pre-treatment technologies including high-pressure processing, pulsed electric field, ultraviolet irradiation, and ultrasound. Sound waves that have a frequency >20 kHz, which is above the upper limit of the audible frequency range, are referred to as "ultrasound". Ultrasonication (US) is a non-thermal technology, that has mechanical, cavitational, and sponge effects on food materials. Ultrasound pre-treatment enhances the drying characteristics by producing microchannels in the food tissue, facilitating internal moisture diffusion in the finished product, and lowering the barrier to water migration. The goal of ultrasound pre-treatment is to save processing time, conserve energy, and enhance the quality, safety, and shelf-life of food products. This study presents a comprehensive overview of the fundamentals of ultrasound, its mechanism, and how the individual effects of ultrasonic pre-treatment and the interactive effects of ultrasound-assisted technologies affect the drying kinetics, bioactive components, color, textural, and sensory qualities of food. The difficulties that can arise when using ultrasound technology as a drying pretreatment approach, such as inadequate management of heat, the employment of ultrasound at a limited frequency, and the generation of free radicals, have also been explained.


Assuntos
Dessecação , Manipulação de Alimentos , Manipulação de Alimentos/métodos , Dessecação/métodos , Cinética , Fenômenos Químicos , Alimentos
3.
Ultrason Sonochem ; 92: 106279, 2023 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-36580835

RESUMO

In this study, the pesticide (acetamiprid, deltamethrin, and pyridaben) removal and physicochemical quality improvement of vine (Vitis vinifera) leaf were examined using ultrasonic and traditional cleaning for 5, 10, and 15 min. After an ultrasonic cleaning procedure at 37 kHz for 10 min, acetamiprid, deltamethrin, and pyridaben in vine leaf were reduced by 54.76, 58.22, and 54.55 %, respectively. Furthermore, the total phenolic content (TPC) in vine leaf increased to 13.45 mg GAE/g DW compared to that in control samples using traditional cleaning (10.37 mg GAE/g DW), but there were no significant differences in DPPH radical scavenging activity. After 15 min of conventional cleaning, the total chlorophyll and total carotenoid content of leaves were found to be lowest among all samples, at 6.52 mg/kg and 0.48 mg/kg, respectively. In conclusion, when compared to conventional cleaning methods, ultrasonic cleaning with no chemicals or heat treatment has proven to be a successful and environmentally friendly application in reducing commonly used pesticides and improving the physicochemical qualities of leaves.


Assuntos
Praguicidas , Vitis , Vitis/química , Praguicidas/análise , Fenóis/análise , Folhas de Planta/química , Extratos Vegetais/química , Antioxidantes/química
4.
J Esthet Restor Dent ; 35(1): 291-298, 2023 01.
Artigo em Inglês | MEDLINE | ID: mdl-36478642

RESUMO

BACKGROUND: Transverse maxillary deficiency, typically characterized by the clinical manifestations of unilateral or bilateral crossbite, is a common orthodontic discrepancy. The primary goal of maxillary expansion should be to obtain a nearly maximum width increase in the basal bone of the constricted maxilla and to avoid the dental expansion of the anchor teeth. The introduction of miniscrew anchorage-supported rapid maxillary expansion (MARPE) devices has helped increase the feasibility of obtaining nonsurgical transverse correction in late adolescents and young adults with optimum orthopedic effects. However, the success rate of MARPE shows a negative correlation with age. Although MARPE offers an effective method for correcting a transverse skeletal deficiency, given the appliance cost and increased risk for complications, it could present challenges for adult patients and practitioners in daily practice. AIMS: In this article, current advances in maxillary skeletal expansion are summarized, and a new MARPE concept is introduced. CONCLUSION: The new MARPE design offers several advantages to other existing methods: (1) it can be installed directly to the patient in the clinical setting with no additional laboratory waiting times. (2) It is purely a bone-borne appliance. (3) The appliance is designed to be placed in the thickest part of the anterior palate to maximize the cortical and trabecular bone support. (4) Allows for bicortical placement of the miniscrews with no perforations in the nasal floor. Finally, (5) offers an esthetic and minimalistic approach to maxillary skeletal expansion in late adolescent and adult patients.


Assuntos
Má Oclusão , Técnica de Expansão Palatina , Adulto Jovem , Adolescente , Humanos , Maxila/cirurgia , Tomografia Computadorizada de Feixe Cônico , Palato
5.
Ultrason Sonochem ; 90: 106184, 2022 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-36194948

RESUMO

Impact of various ultrasound pretreatment and microwave drying parameters on the qualitative and antioxidant characteristics of Inula viscosa (L.) was investigated in this study. The leaves of Inula viscosa (L.) were sonicated for 10, 20, and 30 min in an ultrasonic bath (37 kHz, 150 Watts). Microwave drying was done at three distinct times (1, 3, and 5 min) and with three different microwave power levels (100, 180, and 300 Watts). Microwave dried samples were tested for color characteristics (L*, a*, b*), chlorophyll, carotenoid, total phenol, and antioxidant content. All dried samples were prepared by infusing them in hot water as tea, and the sensorial properties of teas including odor, color, aroma, and overall acceptability were evaluated by panelists. For 10, 20, and 30 min of ultrasound pretreatment, the L* values of leaves varied from 37.70 to 49.76, 34.97 to 46.25, and 27.88 to 43.34, respectively. The total carotenoid concentration ranged from 0.12 to 0.32 mg/g DW, while the total chlorophyll content was from 0.44 to 0.94 mg/g DW. The antioxidant activity of Inula viscosa (L.) leaves that were dried at 300 Watts for 5 min did not change significantly as a result of ultrasound pretreatment. There was a significant positive correlation between aroma and TPC, as well as between color and overall acceptability. The darkest-colored teas were deemed preferable by the panelists.


Assuntos
Antioxidantes , Inula , Micro-Ondas , Ultrassom , Carotenoides , Clorofila , Cor
6.
Gen Dent ; 55(4): 320-4, 2007.
Artigo em Inglês | MEDLINE | ID: mdl-17682641

RESUMO

Although implant-supported restorations often are preferred for the replacement of missing teeth, their high cost means that they can be given only to patients who can afford them. The clinical reports in this article describe interim conservative restorations made after orthodontic treatment to achieve esthetics, phonation, and function until implant-supported dentures were made. In all cases, the patients who received fiber-reinforced resin composite fixed partial dentures returned for follow-up visits at three-month intervals and reported no complaints during a year of follow-up visits. The desired esthetics can be achieved with temporary conservative treatment until the implant dentures are applied; if this treatment meets the patient's esthetic expectations, the final restoration can be fabricated according to these contours.


Assuntos
Prótese Adesiva , Prótese Parcial Temporária , Arcada Parcialmente Edêntula/reabilitação , Mantenedor de Espaço em Ortodontia , Adulto , Implantes Dentários , Feminino , Humanos , Masculino , Maxila
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