Your browser doesn't support javascript.
loading
Montrer: 20 | 50 | 100
Résultats 1 - 20 de 21
Filtrer
Plus de filtres










Base de données
Gamme d'année
1.
J Dent Anesth Pain Med ; 24(1): 19-35, 2024 Feb.
Article de Anglais | MEDLINE | ID: mdl-38362260

RÉSUMÉ

Background: This study investigated a safe and effective bolus dose and lockout time for patient-controlled sedation (PCS) with dexmedetomidine for dental treatments. The depth of sedation, vital signs, and patient satisfaction were investigated to demonstrate safety. Methods: Thirty patients requiring dental scaling were enrolled and randomly divided into three groups based on bolus doses and lockout times: group 1 (low dose group, bolus dose 0.05 µg/kg, 1-minute lockout time), group 2 (middle dose group, 0.1 µg/kg, 1-minute), and group 3 (high dose group, 0.2 µg/kg, 3-minute) (n = 10 each). ECG, pulse, oxygen saturation, blood pressure, end-tidal CO2, respiratory rate, and bispectral index scores (BIS) were measured and recorded. The study was conducted in two stages: the first involved sedation without dental treatment and the second included sedation with dental scaling. Patients were instructed to press the drug demand button every 10 s, and the process of falling asleep and waking up was repeated 1-5 times. In the second stage, during dental scaling, patients were instructed to press the drug demand button. Loss of responsiveness (LOR) was defined as failure to respond to auditory stimuli six times, determining sleep onset. Patient and dentist satisfaction were assessed before and after experimentation. Results: Thirty patients (22 males) participated in the study. Scaling was performed in 29 patients after excluding one who experienced dizziness during the first stage. The average number of drug administrations until first LOR was significantly lower in group 3 (2.8 times) than groups 1 and 2 (8.0 and 6.5 times, respectively). The time taken to reach the LOR showed no difference between groups. During the second stage, the average time required to reach the LOR during scaling was 583.4 seconds. The effect site concentrations (Ce) was significantly lower in group 1 than groups 2 and 3. In the participant survey on PCS, 8/10 in group 3 reported partial memory loss, whereas 17/20 in groups 1 and 2 recalled the procedure fully or partially. Conclusion: PCS with dexmedetomidine can provide a rapid onset of sedation, safe vital sign management, and minimal side effects, thus facilitating smooth dental sedation.

2.
Small Methods ; : e2301224, 2024 Jan 09.
Article de Anglais | MEDLINE | ID: mdl-38193264

RÉSUMÉ

Colloidal quantum dots (QDs) are widely regarded as advanced emissive materials with significant potential for display applications owing to their excellent optical properties such as high color purity, near-unity photoluminescence quantum yield, and size-tunable emission color. Building upon these attractive attributes, QDs have successfully garnered attention in the display market as down-conversion luminophores and now venturing into the realm of self-emissive displays, exemplified by QD light-emitting diodes (QD-LEDs). However, despite these advancements, there remains a relatively limited body of research on QD patterning technologies, which are crucial prerequisites for the successful commercialization of QD-LEDs. Thus, in this review, an overview of the current status and prospects of QD patterning technologies to accelerate the commercialization of QD-LEDs is provided. Within this review, a comprehensive investigation of three prevailing patterning methods: optical lithography, transfer printing, and inkjet printing are conducted. Furthermore, several exploratory QD patterning techniques that offer distinct advantages are introduced. This study not only paves the way for successful commercialization but also extends the potential application of QD-LEDs into uncharted frontiers.

4.
Adv Mater ; 34(43): e2205504, 2022 Oct.
Article de Anglais | MEDLINE | ID: mdl-35985813

RÉSUMÉ

Electroluminescence from quantum dots (QDs) is a suitable photon source for futuristic displays offering hyper-realistic images with free-form factors. Accordingly, a nondestructive and scalable process capable of rendering multicolored QD patterns on a scale of several micrometers needs to be established. Here, nondestructive direct photopatterning for heavy-metal-free QDs is reported using branched light-driven ligand crosslinkers (LiXers) containing multiple azide units. The branched LiXers effectively interlock QD films via photo-crosslinking native aliphatic QD surface ligands without compromising the intrinsic optoelectronic properties of QDs. Using branched LiXers with six sterically engineered azide units, RGB QD patterns are achieved on the micrometer scale. The photo-crosslinking process does not affect the photoluminescence and electroluminescence characteristics of QDs and extends the device lifetime. This nondestructive method can be readily adapted to industrial processes and make an immediate impact on display technologies, as it uses widely available photolithography facilities and high-quality heavy-metal-free QDs with aliphatic ligands.

5.
Nat Nanotechnol ; 17(9): 952-958, 2022 Sep.
Article de Anglais | MEDLINE | ID: mdl-35953539

RÉSUMÉ

Colloidal quantum dots (QDs) stand at the forefront of a variety of photonic applications given their narrow spectral bandwidth and near-unity luminescence efficiency. However, integrating luminescent QD films into photonic devices without compromising their optical or transport characteristics remains challenging. Here we devise a dual-ligand passivation system comprising photocrosslinkable ligands and dispersing ligands to enable QDs to be universally compatible with solution-based patterning techniques. The successful control over the structure of both ligands allows the direct patterning of dual-ligand QDs on various substrates using commercialized photolithography (i-line) or inkjet printing systems at a resolution up to 15,000 pixels per inch without compromising the optical properties of the QDs or the optoelectronic performance of the device. We demonstrate the capabilities of our approach for QD-LED applications. Our approach offers a versatile way of creating various structures of luminescent QDs in a cost-effective and non-destructive manner, and could be implemented in nearly all commercial photonics applications where QDs are used.

6.
Nat Mater ; 21(2): 246-252, 2022 Feb.
Article de Anglais | MEDLINE | ID: mdl-34795403

RÉSUMÉ

The potential profile and the energy level offset of core-shell heterostructured nanocrystals (h-NCs) determine the photophysical properties and the charge transport characteristics of h-NC solids. However, limited material choices for heavy metal-free III-V-II-VI h-NCs pose challenges in comprehensive control of the potential profile. Herein, we present an approach to such a control by steering dipole densities at the interface of III-V-II-VI h-NCs. The controllable heterovalency at the interface is responsible for interfacial dipole densities that result in the vacuum-level shift, providing an additional knob for the control of optical and electrical characteristics of h-NCs. The synthesis of h-NCs with atomic precision allows us to correlate interfacial dipole moments with the NCs' photochemical stability and optoelectronic performance.

7.
ACS Nano ; 15(12): 20332-20340, 2021 Dec 28.
Article de Anglais | MEDLINE | ID: mdl-34866380

RÉSUMÉ

The state-of-the-art quantum dot (QD) based light-emitting diodes (QD-LEDs) reach near-unity internal quantum efficiency thanks to organic materials used for efficient hole transportation within the devices. However, toward high-current-density LEDs, such as augmented reality, virtual reality, and head-up display, thermal vulnerability of organic components often results in device instability or breakdown. The adoption of a thermally robust inorganic hole transport layer (HTL), such as NiO, becomes a promising alternative, but the large energy offset between the NiO HTL and the QD emissive layer impedes the efficient operation of QD-LEDs. Here, we demonstrate bright and stable all-inorganic QD-LEDs by steering the orientation of molecular dipoles at the surfaces of both the NiO HTL and QDs. We show that the molecular dipoles not only induce the vacuum level shift that helps alleviate the energy offset between the NiO HTL and QDs but also passivate the surface trap states of the NiO HTL that act as nonradiative recombination centers. With the facilitated hole injection into QDs and suppressed electron leakage toward trap sites in the NiO HTL, we achieve all-inorganic QD-LEDs with high external quantum efficiency (6.5% at peak) and brightness (peak luminance exceeding 77 000 cd/m2) along with prolonged operational stability. The approaches and results in the present study provide the design principles for high-performance all-inorganic QD-LEDs suited for next-generation light sources.

8.
Small ; 17(32): e2101204, 2021 Aug.
Article de Anglais | MEDLINE | ID: mdl-34242488

RÉSUMÉ

Due to their anisotropic structure, quantum rods (QRs) feature unique properties that differ from quantum dots, such as suppression of non-radiative Auger recombination and linearly polarized light emission. Despite many potential advantages, the progress of QR-based light-emitting diodes (QR-LEDs) is left behind due to the difficulty in aligning QRs. In this study, polarized electroluminescence emission is reported in high-performance QR-LEDs by employing the Langmuir-Blodgett (LB) technique. The adoption of the LB technique successfully produces a highly dense and smooth QR film with a high degree of alignment. As a result, the aligned QR films exhibit polarized photoluminescence emission with a degree of linear polarization of 2.1. Advantageous features of the LB technique, such as nondestructiveness, precise thickness control, and the nonnecessity of an additional matrix material, allow to fabricate QR-LEDs with the same procedure as the standard spin coating-based scheme. The device is fabricated via the LB technique, which shows excellent device performance, such as the low turn-on voltage of 1.8 V, peak luminance of 56 287 cd m-2 , and peak external quantum efficiency (EQE) of 10.33%. Furthermore, these devices clearly exhibit an indication of polarized electroluminescence emission, which opens new opportunities for QRs in display technologies.

9.
Int J Med Sci ; 18(6): 1432-1441, 2021.
Article de Anglais | MEDLINE | ID: mdl-33628100

RÉSUMÉ

Background: Orthognathic surgery requires red blood cell (RBC) transfusions more frequently than other oral and maxillofacial surgeries. The purpose of this study was to identify reliable predictors for RBC transfusion during bimaxillary orthognathic surgery (BOS). Methods: This retrospective study reviewed 1,616 electronic medical records of patients who underwent BOS during a 5-year period at Seoul National University Dental Hospital. The perioperative variable data were collected from electronic medical records and analyzed by dividing patients into the two groups (non-transfusion and transfusion group). Results: Of the 1,616 patients, 1,311 patients were excluded. The remaining 305 patients were divided into non-transfusion (NTF, n = 256) and transfusion (TF, n = 49) groups. Univariate logistic regression analysis revealed that age, body mass index, the presence of several adjunctive surgeries (including genioplasty, extraction, and mandibular angle reduction), preoperative hemoglobin (Hb) and prothrombin time, surgical time, amount of fluid infusion and blood loss, and mean pulse rate during surgery were significant factors predicting RBC transfusion. Multivariate logistic regression analysis revealed that preoperative Hb and blood loss amount during surgery were significantly related to RBC transfusion in BOS patients. Conclusion: Since blood loss amounts could not be measured preoperatively, we found that the independent predictor associated with RBC transfusion during BOS was a low preoperative Hb level.


Sujet(s)
Perte sanguine peropératoire/statistiques et données numériques , Transfusion d'érythrocytes/statistiques et données numériques , Hémoglobines/analyse , Procédures de chirurgie orthognathique/effets indésirables , Adolescent , Adulte , Facteurs âges , Perte sanguine peropératoire/prévention et contrôle , Indice de masse corporelle , Femelle , Humains , Durée du séjour/statistiques et données numériques , Mâle , Durée opératoire , Période préopératoire , Temps de prothrombine , Reproductibilité des résultats , Études rétrospectives , Appréciation des risques/méthodes , Facteurs de risque , Jeune adulte
10.
J Dent Anesth Pain Med ; 20(5): 293-301, 2020 Oct.
Article de Anglais | MEDLINE | ID: mdl-33195807

RÉSUMÉ

BACKGROUND: The success rate of intubation under direct laryngoscopy is greatly influenced by laryngoscopic grade using the Cormack-Lehane classification. However, it is not known whether grade under direct laryngoscopy can also affects the success rate of nasotracheal intubation using a fiberoptic bronchoscpe, so this study investigated the same. In addition, we investigated other factors that influence the success rate of fiberoptic nasotracheal intubation (FNI). METHODS: FNI was performed by 18 anesthesiology residents under general anesthesia in patients over 15 years of age who underwent elective oral and maxillofacial operations. In all patients, the Mallampati grade was measured. Laryngeal view grade under direct laryngoscopy, and the degree of secretion and bleeding in the oral cavity was measured and divided into 3 grades. The time required for successful FNI was measured. If the intubation time was > 5 minutes, it was evaluated as a failure and the airway was managed by another method. The failure rate was evaluated using appropriate statistical method. Receiver operating characteristic (ROC) curves and area under the curve (AUC) were also measured. RESULTS: A total of 650 patients were included in the study, and the failure rate of FNI was 4.5%. The patient's sex, age, height, weight, Mallampati, and laryngoscopic view grade did not affect the success rate of FNI (P > 0.05). BMI, the number of FNI performed by residents (P = 0.03), secretion (P < 0.001), and bleeding (P < 0.001) grades influenced the success rate. The AUCs of bleeding and secretion were 0.864 and 0.798, respectively, but the AUC of BMI, the number of FNI performed by residents, Mallampati, and laryngoscopic view grade were 0.527, 0.616, 0.614, and 0.544, respectively. CONCLUSION: Unlike in intubation under direct laryngoscopy, in the case of FNI, oral secretion and nasal bleeding had a significant effect on FNI difficulty than Mallampati grade or Laryngeal view grade.

11.
ACS Nano ; 14(12): 17496-17504, 2020 Dec 22.
Article de Anglais | MEDLINE | ID: mdl-33252236

RÉSUMÉ

The charge injection imbalance into the quantum dot (QD) emissive layer of QD-based light-emitting diodes (QD-LEDs) is an unresolved issue that is detrimental to the efficiency and operation stability of devices. Herein, an integrated approach to harmonize the charge injection rates for bright and stable QD-LEDs is proposed. Specifically, the electronic characteristics of the hole transport layer (HTL) is delicately designed in order to facilitate the hole injection from the HTL into QDs and confine the electron overflow toward the HTL. The well-defined exciton recombination zone by the engineered QDs and HTL results in high performance with a peak luminance exceeding 410 000 cd/m2, suppressed efficiency roll-off characteristics (ΔEQE < 5% between 200 and 200 000 cd/m2), and prolonged operational stability. The electric and optoelectronic analyses reveal the charge carrier injection mechanism at the interface between the HTL and QDs and provides the design principle of QD heterostructures and charge transport layers for high-performance QD-LEDs.

12.
J Dent Anesth Pain Med ; 20(3): 155-160, 2020 Jun.
Article de Anglais | MEDLINE | ID: mdl-32617410

RÉSUMÉ

Submental or submandibular intubation has been reported to cause fewer complications than tracheostomy. However, the risk of infection is always inherent because oral wounds are exposed to microbial flora and bacteria in the oral cavity. A novel technique of submandibular intubation was devised to reduce infection and injury to the soft tissues. We would like to report a novel safe technique that can be performed in patients requiring submental or submandibular intubation. This is the first report of submandibular intubation using a sterile disposable camera cable drape. This novel technique of submandibular intubation is safer, more sterile, easier, and less invasive than conventional submandibular intubation.

13.
Nat Commun ; 11(1): 2874, 2020 Jun 08.
Article de Anglais | MEDLINE | ID: mdl-32513918

RÉSUMÉ

Establishing multi-colour patterning technology for colloidal quantum dots is critical for realising high-resolution displays based on the material. Here, we report a solution-based processing method to form patterns of quantum dots using a light-driven ligand crosslinker, ethane-1,2-diyl bis(4-azido-2,3,5,6-tetrafluorobenzoate). The crosslinker with two azide end groups can interlock the ligands of neighbouring quantum dots upon exposure to UV, yielding chemically robust quantum dot films. Exploiting the light-driven crosslinking process, different colour CdSe-based core-shell quantum dots can be photo-patterned; quantum dot patterns of red, green and blue primary colours with a sub-pixel size of 4 µm × 16 µm, corresponding to a resolution of >1400 pixels per inch, are demonstrated. The process is non-destructive, such that photoluminescence and electroluminescence characteristics of quantum dot films are preserved after crosslinking. We demonstrate that red crosslinked quantum dot light-emitting diodes exhibiting an external quantum efficiency as high as 14.6% can be obtained.

14.
ACS Appl Mater Interfaces ; 12(9): 10563-10570, 2020 Mar 04.
Article de Anglais | MEDLINE | ID: mdl-32048828

RÉSUMÉ

The rising demand for eradicating hazardous substances in the workplace has motivated vigorous researches on environmentally sustainable manufacturing processes of colloidal quantum dots (QDs) for their optoelectronic applications. Despite remarkable achievements witnessed in QD materials (e.g., Pb- or Cd-free QDs), the progress in the eco-friendly process is far falling behind and thus the practical use of QDs. Herein, a complete "green" process of QDs, which excludes environmentally unfriendly elements from QDs, ligands, or solvents, is presented. The implant of mono-2-(methacryloyloxy)ethyl succinate (MMES) ligands renders InP/ZnSexS1-x QDs dispersed in eco-friendly polar solvents that are widely accepted in the industry while keeping the photophysical properties of QDs unchanged. The MMES-capped QDs show exceptional colloidal stabilities in a range of green polar solvents that permit uniform inkjet printing of QD dispersion. In addition, MMES-capped QDs are also compatible with commercially available photo-patternable resins, and the cross-linkable moiety within MMES further facilitates the achievement in the formation of well-defined, micrometer-scale patterning of QD optical films. The presented materials, all composed of simple, scalable, and environmentally safe compounds, promise low environmental impact during the processing of QDs and thus will catalyze the practicable use of QDs in a variety of optoelectronic devices.

15.
J Dent Anesth Pain Med ; 19(5): 295-300, 2019 Oct.
Article de Anglais | MEDLINE | ID: mdl-31723670

RÉSUMÉ

Complex regional pain syndrome (CRPS) is rare, characterized by pain from diverse causes, and presents as extreme pain even with minor irritation. General anesthesia may be required for dental treatment because the pain may not be controlled with local anesthesia. However, treatment under general anesthesia is also challenging. A 38-year-old woman with CRPS arrived for outpatient dental treatment under general anesthesia. At the fourth general anesthesia induction, she experienced severe pain resulting from her right toe touching the dental chair. Anesthesia was induced to calm her and continue the treatment. After 55 minutes of general anesthesia, the patient still complained of extreme toe pain. Subsequently, two administrations for intravenous sedation were performed, and discharge was possible in the recovery room approximately 5 h after the pain onset. The pain was not located at the dental treatment site. Although the major factor causing pain relief was unknown, ketamine may have played a role.

16.
Maxillofac Plast Reconstr Surg ; 41(1): 41, 2019 Dec.
Article de Anglais | MEDLINE | ID: mdl-31649902

RÉSUMÉ

BACKGROUNDS: The purpose of this study is to discuss the total joint reconstruction surgery for a patient with recurrent ankylosis in bilateral temporomandibular joints (TMJs) using three-dimensional (3D) virtual surgical planning, computer-aided manufacturing (CAD/CAM)-fabricated surgical guides, and stock TMJ prostheses. CASE PRESENTATION: A 66-year-old female patient, who had a history of multiple TMJ surgeries, complained of severe difficulty in eating and trismus. The 3D virtual surgery was performed with a virtual surgery software (FACEGIDE, MegaGen implant, Daegu, South Korea). After confirmation of the location of the upper margin for resection of the root of the zygoma and the lower margin for resection of the ankylosed condyle, and the position of the fossa and condyle components of stock TMJ prosthesis (Biomet, Jacksonville, FL, USA), the surgical guides were fabricated with CAD/CAM technology. Under general anesthesia, osteotomy and placement of the stock TMJ prosthesis (Biomet) were carried out according to the surgical planning. At 2 months after the operation, the patient was able to open her mouth up to 30 mm without complication. CONCLUSION: For a patient who has recurrent ankylosis in bilateral TMJs, total joint reconstruction surgery using 3D virtual surgical planning, CAD/CAM-fabricated surgical guides, and stock TMJ prostheses may be an effective surgical treatment option.

17.
ACS Appl Mater Interfaces ; 11(43): 40252-40259, 2019 Oct 30.
Article de Anglais | MEDLINE | ID: mdl-31590488

RÉSUMÉ

Balanced charge injection promises high efficiency of quantum dot-based light-emitting diodes (QD-LEDs). The most widely used approach to realize charge injection balance impedes the injection rate of the dominant charge carrier with energetic barriers. However, these approaches often accompany unwanted outcomes (e.g., the increase in operation voltage) that sacrifice the operational stability of devices. Herein, a "positive incentive" approach is proposed to enhance the efficiency and the operational stability of QD-LEDs. Specifically, the supply of hole, an inferior carrier than its counterpart, is facilitated by adopting a thin fullerene (C60) interlayer at the interface between the hole injection layer (MoOX) and hole transport layer (4,4'-bis(9-carbazolyl)-1,1'-biphenyl). The C60 interlayer boosts the hole current by eliminating the universal energy barrier, lowers the operation voltage of QD-LEDs, and enhances the charge balance in the QD emissive layer within the working device. Consequently, QD-LEDs benefitting from the adoption of the C60 interlayer exhibit significantly enhanced device efficiency and operation stability. Grounded on the quantitative assessment of the charge injection imbalance within the QD emissive layer, the impact of electrical parameters of QD-LEDs on their optoelectronic performance and operational stability is also discussed.

18.
J Dent Anesth Pain Med ; 19(4): 181-189, 2019 Aug.
Article de Anglais | MEDLINE | ID: mdl-31501776

RÉSUMÉ

Local anesthetic systemic toxicity (LAST) refers to the complication affecting the central nervous system (CNS) and cardiovascular system (CVS) due to the overdose of local anesthesia. Its reported prevalence is 0.27/1000, and the representative symptoms range from dizziness to unconsciousness in the CNS and from arrhythmias to cardiac arrest in the CVS. Predisposing factors of LAST include extremes of age, pregnancy, renal disease, cardiac disease, hepatic dysfunction, and drug-associated factors. To prevent the LAST, it is necessary to recognize the risk factors for each patient, choose a safe drug and dose of local anesthesia, use vasoconstrictor , confirm aspiration and use incremental injection techniques. According to the treatment guidelines for LAST, immediate application of lipid emulsion plays an important role. Although lipid emulsion is commonly used for parenteral nutrition, it has recently been widely used as a non-specific antidote for various types of drug toxicity, such as LAST treatment. According to the recently published guidelines, 20% lipid emulsion is to be intravenously injected at 1.5 mL/kg. After bolus injection, 15 mL/kg/h of lipid emulsion is to be continuously injected for LAST. However, caution must be observed for >1000 mL of injection, which is the maximum dose. We reviewed the incidence, mechanism, prevention, and treatment guidelines, and a serious complication of LAST occurring due to dental anesthesia. Furthermore, we introduced lipid emulsion that has recently been in the spotlight as the therapeutic strategy for LAST.

19.
J Dent Anesth Pain Med ; 19(4): 239-244, 2019 Aug.
Article de Anglais | MEDLINE | ID: mdl-31501783

RÉSUMÉ

The effectiveness of dental implants in patients with disability, who are non-compliant during treatment, is controversial because of their poor oral health. Thus, oral health-care and management in such patients is concerning. Moreover, limited information is available on prognosis after implant placement. Herein, we describe a patient with schizophrenia who underwent dental implantation under multiple inductions of general anesthesia (5 times) and required conservative treatment and tooth extraction for multiple dental caries and retained roots because of inadequate oral health-care. Postoperatively, fracture of the prosthodontics and progression of dental caries were observed, and with 3 additional inductions of general anesthesia, conservative treatment, implant surgery, and prosthesis implantation were conducted. Postoperative 12-month follow-up since the last prosthesis implantation showed successful results. For patients with schizophrenia, multiple implantation can reduce horizontal bone loss and achieve aesthetic results compared to treatment with removable prosthodontics and could serve as an alternative treatment modality.

20.
J Korean Assoc Oral Maxillofac Surg ; 41(4): 208-12, 2015 Aug.
Article de Anglais | MEDLINE | ID: mdl-26339581

RÉSUMÉ

Keratocystic odontogenic tumor (KCOT) is a common benign tumor of osseous lesions in dental and maxillofacial practice. We describe three cases of large KCOT located in the posterior part of the mandible extending to the angle and ramus region, which were enucleated via sagittal split osteotomy (SSO) of the mandible. There are cases in which a conventional enucleation procedure does not ensure complete excision of the entire lesion without damage to vital structures like the inferior alveolar nerve. In such cases, a SSO approach could be a better choice than conventional methods. The purpose of this article is to describe our experience using unilateral mandibular SSO for removal of a KCOT from the mandible.

SÉLECTION CITATIONS
DÉTAIL DE RECHERCHE
...