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1.
Orthod Craniofac Res ; 2024 Jul 23.
Artículo en Inglés | MEDLINE | ID: mdl-39041290

RESUMEN

OBJECTIVE: The aim of this study was to evaluate retention efficacy by assessing retention stability and patient perspectives according to type of circumferential retainer: the wrap-around circumferential retainer (WCR) and customized clear retainer (CCR). MATERIALS AND METHODS: This cohort follow-up study involved 52 patients aged 18-62 who underwent fixed-appliance orthodontic treatment without extractions or orthognathic surgery. Following screening consenting participants were divided into WCR and CCR groups. All participants before follow-up received fixed retainers for the upper and lower anteriors and respective removable retainers within 2 weeks post-debond. Intraoral scans and lateral cephalograms were taken immediately after debonding (T0) and again 12 months later. Dentoalveolar changes in several measurements were compared to evaluate retention efficacy. Surveys were conducted at 1 month (T1) and 12 months (T2) post-debonding to assess changes in patient experiences. Outcome assessments were blinded. Paired T-tests and independent T-tests were used for intragroup and intergroup comparisons of dentoalveolar measurements, respectively. Survey responses were analysed using the Pearson Chi-Square test. RESULTS: The final assessment included 32 participants. Model analysis revealed no significant differences between the groups, except for maxillary intermolar width (p = .033). In the WCR group, the cephalometric analysis indicated a significant increase in the incisor mandibular plane angle (p = .002) and a decrease in the interincisal angle (p = .014), while changes in the CCR group were statistically non-significant. Patient attitude evaluation showed similar trends for wear time and overall satisfaction. However, a higher percentage of respondents in the WCR group reported irritation when wearing the retainers (p = .037) at T1 and discomfort related to speech (p = .038) at T2. CONCLUSIONS: CCR showed better retention efficacy in terms of lower incisor inclination. Patients experienced relatively less irritation and speech discomfort with CCRs.

2.
J Periodontal Res ; 58(2): 381-391, 2023 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-36641544

RESUMEN

INTRODUCTION: Microbiome from a "healthy cohort" is used as a reference for comparison to cases and intervention. However, the studies with cohort-based clinical research have not sufficiently accounted for the multistability in oral microbial community. The screening is limited to phenotypic features with marked variations in microbial genomic markers. Herein, we aimed to assess the stability of the oral microbiome across time from an intervention-free "healthy" cohort. METHODS: We obtained 33 supragingival samples of 11 healthy participants from the biobank. For each participant, we processed one sample as baseline (T0) and two samples spaced at 1-month (T1) and 3-month (T2) intervals for 16S ribosomal RNA gene sequencing analysis. RESULTS: We observed that taxonomic profiling had a similar pattern of dominant genera, namely, Rothia, Prevotella, and Hemophilus, at all time points. Shannon diversity revealed a significant increase from T0 (p < .05). Bray Curtis dissimilarity was significant (R = -.02, p < .01) within the cohort at each time point. Community stability had negative correlation to synchrony (r = -.739; p = .009) and variance (r = -.605; p = .048) of the species. Clustering revealed marked differences in the grouping patterns between the three time points. For all time points, the clusters presented a substantially dissimilar set of differentially abundant taxonomic and functional biomarkers. CONCLUSION: Our observations indicate towards the presence of multistable states within the oral microbiome in an intervention-free healthy cohort. For a conclusive and meaningful long-term reference, dental clinical research should account for multistability in the personalized therapy approach to improve the identification and classification of reliable markers.


Asunto(s)
Microbiota , Micrococcaceae , Humanos , ARN Ribosómico 16S/genética , Microbiota/genética , Estudios de Cohortes , Biomarcadores , Micrococcaceae/genética
3.
BMC Oral Health ; 23(1): 164, 2023 03 22.
Artículo en Inglés | MEDLINE | ID: mdl-36949457

RESUMEN

BACKGROUND: The purpose of this study is to evaluate stability of vertical dimension following total arch intrusion using miniscrews by measuring the change during treatment and relapse amount after more than one year of retention. METHODS: Thirty patients (6 men, 24 women) were included in this study. Lateral cephalographs were taken with conventional radiography at the start of treatment (T0), after treatment (T1), and at least one year after treatment (T2). The evaluation was performed by measuring changes of selected parameters during treatment and the extent of relapse after more than one year. RESULTS: During total arch intrusion treatment (T1-T0), anterior and posterior teeth intruded significantly. The mean vertical distance between the maxillary posterior teeth and palatal plane was reduced by 2.30 mm (P < 0.001). The mean vertical distance between the maxillary anterior teeth and palatal plane was reduced by 2.04 mm (P < 0.001). The anterior facial height was also reduced by 2.70 mm (P < 0.001). During retention period (T2-T1), the vertical distance between the maxillary anterior teeth and the palatal plane significantly increased by 0.92 mm (P < 0.001). The anterior facial height increased by 0.81 mm (P < 0.01). CONCLUSIONS: Anterior facial height significantly decreases after treatment. During retention period, relapse of AFH and maxillary anterior teeth observed. There was no correlation between initial amount of AFH, mandibular plane angle, or SNPog and posttreatment AFH relapse. However, there was a significant correlation between the amount of intrusion of anterior and posterior teeth achieved by the treatment and the extent of relapse.


Asunto(s)
Diente , Masculino , Humanos , Femenino , Dimensión Vertical , Maxilar/diagnóstico por imagen , Técnicas de Movimiento Dental/métodos , Cefalometría/métodos , Recurrencia
4.
Clin Oral Investig ; 26(3): 2993-3003, 2022 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-34821980

RESUMEN

OBJECTIVES: This study aimed to assess the success rate and the amount of suture separation after the miniscrew-assisted rapid palatal expansion (MARPE) procedure in relation to the chronological age and sex of the patients. MATERIALS AND METHODS: The periapical radiographs of 215 subjects (95 male; 120 female; range, 6-60 years) who had undergone MARPE treatment were retrospectively analyzed. The success of suture separation was determined and, in suture-separated subjects, the amount of suture separation was evaluated by suture separation ratio calculated from the periapical radiograph obtained after active expansion. Association tests were performed using linear-by-linear association, the Jonckheere-Terpstra test, Fisher's exact test, and the Mann-Whitney U test, and linear regression models were also developed. RESULTS: The success rate of suture separation was 61.05% in male, 94.17% in female, and 79.53% in both sexes. There was a statistically significant association between older age and suture nonseparation in male (p < 0.001), but not in female (p = 0.221). In suture-separated subjects, there was a statistically significant trend toward a low amount of suture separation with older age subgroups in both sexes (p < 0.001); however, there was no statistically significant difference in the amount of suture separation between male and female in all age subgroups. CONCLUSIONS: Older patients treated with MARPE, particularly in male, may have a reduced likelihood of both success in suture separation and sufficient basal bone expansion. CLINICAL RELEVANCE: This study demonstrates that clinicians should consider that the success rate of MARPE and the amount of suture separation may depend on chronological age and sex.


Asunto(s)
Maxilar , Técnica de Expansión Palatina , Femenino , Humanos , Masculino , Hueso Paladar , Estudios Retrospectivos , Suturas
5.
Am J Orthod Dentofacial Orthop ; 162(1): 93-102.e1, 2022 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-35772876

RESUMEN

INTRODUCTION: In this study, we aimed to evaluate and compare the bracket positioning accuracy of the indirect bonding (IDB) transfer tray fabricated in-clinic using the tray printing (TP) and marker-model printing methods (MP). METHODS: The TP group was further divided into 2 groups (single-tray printing [STP] and multiple-tray printing [MTP]) depending on the presence of a tray split created using the 3-dimensional (3D) software. Five duplicated plaster models were used for each of the 3 experimental groups, and a total of 180 artificial teeth, except the second molar, were evaluated in the experiment. The dental model was scanned using a model scanner (E3; 3Shape Dental Systems, Copenhagen, Denmark). Virtual brackets were placed on facial axis points, and the IDB trays were designed and fabricated using a 3D printer (VIDA; EnvisionTEC, Mich). The accuracy of bracket positioning was evaluated by comparing the planned bracket positions and the actual bracket positions using 3D analysis on inspection software. The main effects and first-order interaction effects were analyzed together by analysis for the analysis of variance. RESULTS: The mean distance and height errors were significantly lower in the STP group than those in the MP and MTP groups (P <0.05). The mean distance error was 0.06 mm in the STP group and 0.09 mm in the MP and MTP groups. The mean height error was 0.10 mm in the STP group and 0.15 mm and 0.18 mm in MP and MTP groups, respectively. However, no significant differences were observed in the angular errors among the 3 groups. CONCLUSIONS: The in-office-fabricated IDB system with computer-aided design and 3D printer is clinically applicable after considering the linear and angular errors. We recommend IDB trays fabricated using the STP method owing to the lower frequency of bracket positioning errors and ease of fabrication.


Asunto(s)
Recubrimiento Dental Adhesivo , Soportes Ortodóncicos , Diseño Asistido por Computadora , Recubrimiento Dental Adhesivo/métodos , Humanos , Modelos Dentales , Impresión Tridimensional
6.
BMC Oral Health ; 22(1): 114, 2022 04 08.
Artículo en Inglés | MEDLINE | ID: mdl-35395801

RESUMEN

BACKGROUND: This prospective randomized clinical trial aimed to evaluate the immediate and short-term skeletal, dentoalveolar, and periodontal effects of rapid palatal expansion (RPE) and miniscrew-assisted RPE (MARPE) in adolescent and young adult patients. METHODS: This study followed a two-arm, parallel, randomized clinical trial design that recruited patients with transverse maxillary deficiency in a 1:1 allocation ratio. Forty patients (14 men and 26 women) requiring maxillary expansion were randomly allocated to the RPE (n = 20, age = 14.0 ± 4.5) or MARPE (n = 20, age = 14.1 ± 4.2) groups. The assignment was performed via computer-generated block randomization, with a block size of four. Upon identical (35 turns) amount of expansion, low-dose cone-beam computed tomography images were taken before treatment (T0), immediately after expansion (T1), and after a 3-month consolidation period (T2). The primary outcome of this study comprised the assessment of midpalatal suture separation. Secondary outcomes included, skeletal, dentoalveolar, and periodontal measurements, which were performed at each time point. RESULTS: The frequency of midpalatal suture separation was 90% (18/20) and 95% (19/20) for the RPE and MARPE groups, respectively. A greater increase in nasal width in the molar region (M-NW) and greater palatine foramen (GPF) was observed immediately after the expansion (T1-T0) and consolidation periods (T2-T0) in the MARPE group compared to the RPE group (P < 0.05). The MARPE and RPE groups showed similar dentoalveolar changes except for the maxillary width (PM-MW, M-MW). The MARPE group presented greater bilateral first premolar (PM-MW) and molar (M-MW) maxillary width in relation to the RPE group (P < 0.05). Through the expansion and consolidation periods (T2-T0), lesser buccal displacement of the anchor teeth was observed in the MARPE group (PM-BBPT, PM-PBPT, M-BBPT [mesial and distal roots], and M-PBPT)( P < 0.05). CONCLUSIONS: Midpalatal suture separation was observed in 90% and 95% of patients in the RPE and MARPE groups, respectively. Both RPE and MARPE groups exhibited significant triangular basal bone expansion and skeletal relapse during consolidation. Under identical amounts of expansion, the MARPE group showed lower decrease in the skeletal, dentoalveolar and periodontal variables after consolidation. The reinforcement of RPE with miniscrews contributes to the maintenance of the basal bone during consolidation period. Trial registration WHO Institutional Clinical Trials Registry Platform (IRB No. KCT0006871 / Registration date 27/12/2021).


Asunto(s)
Técnica de Expansión Palatina , Tomografía Computarizada de Haz Cónico Espiral , Adolescente , Niño , Tomografía Computarizada de Haz Cónico/métodos , Femenino , Humanos , Masculino , Maxilar/diagnóstico por imagen , Maxilar/cirugía , Recurrencia Local de Neoplasia , Hueso Paladar/diagnóstico por imagen , Estudios Prospectivos , Adulto Joven
7.
Orthod Craniofac Res ; 24 Suppl 1: 48-58, 2021 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-33275826

RESUMEN

Previously, in the case of malocclusion owing to skeletal discrepancy in adults, the amount of tooth movement was limited since there was no reliable skeletal anchorage device. The only way to treat this case was by repositioning the maxilla and mandible via orthognathic surgery, but most patients are reluctant to undergo surgery owing to the risk and expenses incurred. However, with the current introduction and use of miniscrews as temporary anchorage devices, the entire dental arch can be relocated to a target position without surgery, thus broadening the scope of non-surgical orthodontic treatment compared to the past. For a non-surgical approach to improve skeletal discrepancy, anteroposterior, vertical and transverse displacements of the dental arch are necessary. In this case, the localization of the centre of resistance of the whole arch must precede the appliance design with an appropriate biomechanical design. Especially, in the transverse dimension, the envelope of discrepancy is reportedly narrow, and the tooth movement must accompany the orthopaedic correction involving the midpalatal suture expansion. Recently, in adults with transverse maxillomandibular discrepancy, miniscrew-assisted rapid palatal expansion (MARPE) can be performed. Moreover, compared to surgically assisted rapid palatal expansion, MARPE reduces the cost to the patient and achieves clinically acceptable stable maxillary expansion. In this article, we will discuss the role of total arch movement and MARPE in widening the scope of non-surgical orthodontic treatment, despite the inherent limitations of miniscrews' mechanical aspects.


Asunto(s)
Métodos de Anclaje en Ortodoncia , Técnica de Expansión Palatina , Adulto , Humanos , Mandíbula , Maxilar , Diseño de Aparato Ortodóncico , Técnicas de Movimiento Dental
8.
Clin Oral Investig ; 25(11): 6321-6333, 2021 Nov.
Artículo en Inglés | MEDLINE | ID: mdl-33822289

RESUMEN

OBJECTIVES: This study investigated the association of changes in cementum protein-1 (CEMP-1), dentine phosphoprotein (DPP), and c-terminal cross-linked telopeptide of type I collagen (CTX-I) levels in human gingival crevicular fluid (GCF) under constant load with external root resorption volume and amount of tooth movement. MATERIALS AND METHODS: In total, 11 healthy adult patients (mean age, 23.5 years [range, 18.3-37.7]; four men and seven women) were enrolled. GCF samples were obtained from premolars at T0, T1 (1 day), T2 (1 week), T3 (2 weeks), T4 (4 weeks), and T5 (8 weeks) under constant 100-gm buccal tipping force. Opposite premolars were used as controls. Teeth were extracted at T5, followed by quantification of external root resorption volume and histological analysis. RESULTS: In the test group, T5/T0 ratios of CEMP-1 and DPP levels, differential CEMP-1 levels between T5 and T0, and differential DPP levels between T2 and T0 correlated positively with root resorption volume (r = 0.734, 0.730, 0.627, and 0.612, respectively, all p < 0.05). CEMP-1 levels at T0 and T3 correlated negatively with root resorption volume (r = -0.603 and -0.706; all p < 0.05). CTX-I levels at T5 correlated positively with the amount of tooth movement (r = 0.848, p < 0.01). CONCLUSIONS: Alterations in CEMP-1 and DPP levels in human GCF at specific timepoints during orthodontic treatment may be associated with different degrees of external root resorption. CLINICAL RELEVANCE: This study demonstrates that changes in the levels of tissue-specific biomarkers in GCF may facilitate early detection of external root resorption during orthodontic tooth movement.


Asunto(s)
Resorción Radicular , Adulto , Diente Premolar , Biomarcadores/análisis , Femenino , Líquido del Surco Gingival/química , Humanos , Masculino , Técnicas de Movimiento Dental , Adulto Joven
9.
Int J Mol Sci ; 22(1)2021 Jan 03.
Artículo en Inglés | MEDLINE | ID: mdl-33401545

RESUMEN

Poly(methyl methacralyate) (PMMA) has long been used in dentistry as a base polymer for dentures, and it is recently being used for the 3D printing of dental materials. Despite its many advantages, its susceptibility to microbial colonization remains to be overcome. In this study, the interface between 3D-printed PMMA specimens and oral salivary biofilm was studied following the addition of zwitterionic materials, 2-methacryloyloxyethyl phosphorylcholine (MPC) or sulfobetaine methacrylate (SB). A significant reduction in bacterial and biofilm adhesions was observed following the addition of MPC or SB, owing to their protein-repellent properties, and there were no significant differences between the two test materials. Although the mechanical properties of the tested materials were degraded, the statistical value of the reduction was minimal and all the properties fulfilled the requirements set by the International Standard, ISO 20795-2. Additionally, both the test materials maintained their resistance to biofilm when subjected to hydrothermal fatigue, with no further deterioration of the mechanical properties. Thus, novel 3D-printable PMMA incorporated with MPC or SB shows durable oral salivary biofilm resistance with maintenance of the physical and mechanical properties.


Asunto(s)
Materiales Biocompatibles/farmacología , Biopelículas/efectos de los fármacos , Resinas Compuestas/química , Materiales Dentales/farmacología , Boca/efectos de los fármacos , Polímeros/química , Impresión Tridimensional/instrumentación , Adhesión Bacteriana , Biopelículas/crecimiento & desarrollo , Humanos , Ensayo de Materiales , Metacrilatos/química , Boca/microbiología , Fosforilcolina/análogos & derivados , Fosforilcolina/química , Streptococcus mutans/efectos de los fármacos , Streptococcus mutans/metabolismo
10.
Am J Orthod Dentofacial Orthop ; 159(1): 30-40, 2021 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-33127204

RESUMEN

INTRODUCTION: We evaluated soft-tissue thickness changes after bimaxillary surgery according to vertical facial patterns in patients with skeletal Class III malocclusion with mandibular prognathism. METHODS: Forty-three Korean patients (16 men and 27 women; mean age, 22.6 ± 4.1 years) with skeletal Class III malocclusion who underwent bimaxillary surgery were divided into 2 groups: normal-angle group (N group) and high-angle group (H group), on the basis of the presurgical angle of the mandibular plane relative to the sella-nasion plane (SN-MP). Changes in hard-tissue landmarks and soft-tissue thickness before and after surgery were analyzed from reconstructed 3-dimensional cone-beam computed tomography images. Postoperative soft-tissue thickness in both groups was compared with that in 40 patients with normal skeletal Class I malocclusion in the reference group. RESULTS: Group N (27°-37°) and group H (>37°) did not differ significantly in terms of sex and age before surgery. Preoperative pogonion (Pog) thickness was significantly less in group H (9.7 ± 1.6 mm) than in group N (10.8 ± 1.9 mm) (P = 0.042). Adjusted multiple linear regression analysis showed a weak positive linear relationship between the SN-MP before surgery and soft-tissue Pog thickness change (R2 of 0.361; P = 0.001) after surgery, but the area below the lower lips was not completely normalized despite surgery. CONCLUSIONS: The thickness of the soft-tissue Pog may increase slightly after surgery in patients with skeletal Class III malocclusion with a higher preoperative mandibular plane angle, but normalization in the area cannot be completely achieved despite surgery.


Asunto(s)
Maloclusión de Angle Clase III , Mandíbula , Adolescente , Adulto , Cefalometría , Cara/diagnóstico por imagen , Femenino , Humanos , Masculino , Maloclusión de Angle Clase III/diagnóstico por imagen , Maloclusión de Angle Clase III/cirugía , Mandíbula/diagnóstico por imagen , Mandíbula/cirugía , Maxilar/diagnóstico por imagen , Maxilar/cirugía , Adulto Joven
11.
Am J Orthod Dentofacial Orthop ; 159(2): 158-166, 2021 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-33243706

RESUMEN

INTRODUCTION: The aim of this research was to verify that ultraviolet light (UV)-photofunctionalization improves the success rate and biomechanical stability of miniscrews regardless of length, and to evaluate the comparability of biomechanical stability between UV-photofunctionalized miniscrews with short lengths and untreated miniscrews with conventional lengths. METHODS: Eight male beagles (age, 12-15 months; weight, 10-13 kg) received a total of 64 miniscrews, including 7-mm and 4-mm untreated and UV-photofunctionalized, acid-etched miniscrews with the use of a random block design. The cumulative success rates were examined in all studied groups. The insertion and removal torques and screw mobility were measured. Microcomputed tomographic scans and histomorphometric analyses were performed at 8 weeks postoperatively. RESULTS: The success rates of 7-mm UV-untreated and UV-photofunctionalized miniscrews were 87.5% and 100%, respectively, vs 43.8% for the 4-mm UV-untreated and 4-mm UV-photofunctionalized miniscrews. The rates were significantly different in accordance with the length (P <0.001). There were no differences in the insertion and removal torque and screw mobility between groups according to the length or UV treatment. However, the 4-mm UV-untreated miniscrews yielded a mean bone area ratio of 6.35 ± 7.43%, whereas the 7-mm UV-photofunctionalized miniscrew yielded a mean ratio of 32.17 ± 8.34% (P = 0.037). CONCLUSIONS: The UV-photofunctionalization significantly increased the biomechanical stability and led to increased bone and miniscrew contact area in dogs with miniscrews of the same length. However, the most important factor that affected the success rate of the miniscrew was the length.


Asunto(s)
Métodos de Anclaje en Ortodoncia , Oseointegración , Animales , Tornillos Óseos , Huesos , Perros , Masculino , Titanio , Torque , Rayos Ultravioleta
12.
J Chem Phys ; 152(12): 124110, 2020 Mar 31.
Artículo en Inglés | MEDLINE | ID: mdl-32241122

RESUMEN

ACE-Molecule (advanced computational engine for molecules) is a real-space quantum chemistry package for both periodic and non-periodic systems. ACE-Molecule adopts a uniform real-space numerical grid supported by the Lagrange-sinc functions. ACE-Molecule provides density functional theory (DFT) as a basic feature. ACE-Molecule is specialized in efficient hybrid DFT and wave-function theory calculations based on Kohn-Sham orbitals obtained from a strictly localized exact exchange potential. It is open-source oriented calculations with a flexible and convenient development interface. Thus, ACE-Molecule can be improved by actively adopting new features from other open-source projects and offers a useful platform for potential developers and users. In this work, we introduce overall features, including theoretical backgrounds and numerical examples implemented in ACE-Molecule.

13.
Int J Mol Sci ; 21(23)2020 Nov 29.
Artículo en Inglés | MEDLINE | ID: mdl-33260367

RESUMEN

Biofilms are formed on surfaces inside the oral cavity covered by the acquired pellicle and develop into a complex, dynamic, microbial environment. Oral biofilm is a causative factor of dental and periodontal diseases. Accordingly, novel materials that can resist biofilm formation have attracted significant attention. Zwitterionic polymers (ZPs) have unique features that resist protein adhesion and prevent biofilm formation while maintaining biocompatibility. Recent literature has reflected a rapid increase in the application of ZPs as coatings and additives with promising outcomes. In this review, we briefly introduce ZPs and their mechanism of antifouling action, properties of human oral biofilms, and present trends in anti-biofouling, zwitterionic, dental materials. Furthermore, we highlight the existing challenges in the standardization of biofilm research and the future of antifouling, zwitterated, dental materials.


Asunto(s)
Materiales Biocompatibles/farmacología , Biopelículas/efectos de los fármacos , Materiales Dentales/farmacología , Adhesión Bacteriana/efectos de los fármacos , Humanos , Boca/microbiología , Polímeros/química , Polímeros/farmacología
14.
Int J Mol Sci ; 21(17)2020 Aug 24.
Artículo en Inglés | MEDLINE | ID: mdl-32846976

RESUMEN

The surface molecular chemistry, such as amine functionality, of biomaterials plays a crucial role in the osteogenic activity of relevant cells and tissues during hard tissue regeneration. Here, we examined the possibilities of creating amine functionalities on the surface of titanium by using the nonthermal atmospheric pressure plasma jet (NTAPPJ) method with humidified ammonia, and the effects on human mesenchymal stem cell (hMSC) were investigated. Titanium samples were subjected to NTAPPJ treatments using nitrogen (N-P), air (A-P), or humidified ammonia (NA-P) as the plasma gas, while control (C-P) samples were not subjected to plasma treatment. After plasma exposure, all treatment groups showed increased hydrophilicity and had more attached cells than the C-P. Among the plasma-treated samples, the A-P and NA-P showed surface oxygen functionalities and exhibited greater cell proliferation than the C-P and N-P. The NA-P additionally showed surface amine-related functionalities and exhibited a higher level of alkaline phosphatase activity and osteocalcin expression than the other samples. The results can be explained by increases in fibronectin absorption and focal adhesion kinase gene expression on the NA-P samples. These findings suggest that NTAPPJ technology with humidified ammonia as a gas source has clinical potential for hard tissue generation.


Asunto(s)
Aminas/química , Diferenciación Celular , Células Madre Mesenquimatosas/fisiología , Gases em Plasma/farmacología , Andamios del Tejido/química , Titanio/química , Amoníaco/química , Técnicas de Cultivo de Célula/instrumentación , Técnicas de Cultivo de Célula/métodos , Diferenciación Celular/efectos de los fármacos , Células Cultivadas , Materiales Biocompatibles Revestidos/química , Materiales Biocompatibles Revestidos/farmacología , Humanos , Ensayo de Materiales , Osteoblastos/efectos de los fármacos , Osteoblastos/fisiología , Osteogénesis/efectos de los fármacos , Osteogénesis/fisiología , Propiedades de Superficie/efectos de los fármacos
15.
Cleft Palate Craniofac J ; 56(6): 827-830, 2019 07.
Artículo en Inglés | MEDLINE | ID: mdl-30453769

RESUMEN

Patients with cleft lip and palate sometimes have a retruded maxilla. Here, we describe the case of a young man in whom crowding of the maxillary teeth and an anteroposterior discrepancy of the maxilla were resolved by premaxillary distraction osteogenesis (DO) using 3 individual intraoral distractors. Our experience in this patient confirms that premaxillary DO with 3 intraoral distractors and preoperative simulation can achieve stable maxillary advancement and arch expansion without impairing velopharyngeal incompetence.


Asunto(s)
Labio Leporino , Fisura del Paladar , Osteogénesis por Distracción , Cefalometría , Humanos , Masculino , Maxilar , Osteotomía Le Fort
16.
Chemistry ; 24(47): 12354-12358, 2018 Aug 22.
Artículo en Inglés | MEDLINE | ID: mdl-29473970

RESUMEN

Machine learning based on big data has emerged as a powerful solution in various chemical problems. We investigated the feasibility of machine learning models for the prediction of activation energies of gas-phase reactions. Six different models with three different types, including the artificial neural network, the support vector regression, and the tree boosting methods, were tested. We used the structural and thermodynamic properties of molecules and their differences as input features without resorting to specific reaction types so as to maintain the most general input form for broad applicability. The tree boosting method showed the best performance among others in terms of the coefficient of determination, mean absolute error, and root mean square error, the values of which were 0.89, 1.95, and 4.49 kcal mol-1 , respectively. Computation time for the prediction of activation energies for 2541 test reactions was about one second on a single computing node without using accelerators.

17.
J Oral Maxillofac Surg ; 76(8): 1753-1762, 2018 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-29549017

RESUMEN

PURPOSE: The aim of the present study was to compare the long-term stability of bimaxillary surgery using an intraoral vertical ramus osteotomy (IVRO) with and without presurgical orthodontic treatment. MATERIALS AND METHODS: The present retrospective study included 31 consecutive patients with skeletal Class III malocclusions who had undergone bimaxillary surgery (Le Fort I osteotomy and bilateral IVRO). Patients were divided into 2 groups based on treatment type: pre-orthodontic orthognathic surgery (POGS; n = 17) and conventional surgery with presurgical orthodontic treatment (CS; n = 14). Lateral cephalograms were obtained before surgery, 1 day after surgery, 1 month after surgery, 1 year after surgery, and 2 years after surgery to evaluate skeletal and soft tissue changes between the 2 groups. Data were analyzed using χ2 tests, Mann-Whitney U tests, repeated-measures analyses of variance, and independent t tests. RESULTS: There was no significant difference in skeletal or soft tissue measurements-with the exception of the angle between the sella-and-nasion plane and the occlusal plane (SN-OP; P < .001)-between the CS and POGS groups at 2 years after IVRO. The SN-OP had increased in the CS group but decreased in the POGS group at 2 years after surgery. CONCLUSIONS: These findings suggest that POGS and CS have similar long-term stability in patients with skeletal Class III malocclusion.


Asunto(s)
Maloclusión de Angle Clase III/cirugía , Osteotomía Maxilar/métodos , Procedimientos Quirúrgicos Ortognáticos/métodos , Adolescente , Cefalometría , Femenino , Humanos , Masculino , Ortodoncia Correctiva , Osteotomía Le Fort , Osteotomía Sagital de Rama Mandibular/métodos , Estudios Retrospectivos , Resultado del Tratamiento , Adulto Joven
18.
Phys Chem Chem Phys ; 19(15): 10177-10186, 2017 Apr 12.
Artículo en Inglés | MEDLINE | ID: mdl-28374031

RESUMEN

Density functional theory (DFT) has been an essential tool for electronic structure calculations in various fields. In particular, its hybrid method including the Hartree-Fock (HF) exchange term remarkably improves the reliability of DFT for chemical applications and computational material design. There are two different types of exchange-correlation potential that can be derived from hybrid functionals. The conventional approach adopts a non-multiplicative potential including the non-local HF exchange operator. Herein, we propose to use a local multiplicative potential as an alternative for accurate excited state calculations. We show that such a local potential can be derived from existing global hybrid functionals using the optimized effective potential method. As a proof-of-concept, we chose PBE0 and investigated its performance for the Caricato benchmark set. Unlike the conventional one, the local potential produced orbital energy gaps with no strong dependence on the mixing ratio as a good approximation for optical excitations. Furthermore, its time-dependent DFT resulted in a surprisingly small mean absolute error even with a local density approximation kernel, surpassing all reported values with various popular functionals. In particular, most excitations were dictated by single orbital transitions due to physically meaningful virtual orbitals, which is beneficial to clear interpretations in the molecular orbital picture.

19.
J Formos Med Assoc ; 116(4): 313-321, 2017 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-27421175

RESUMEN

BACKGROUND/PURPOSE: Few studies have evaluated craniofacial growth in boys and girls with idiopathic short stature (ISS) during growth hormone (GH) treatment. The aim of this study was to evaluate the effect of GH treatment on craniofacial growth in children with ISS, compared with those with growth hormone deficiency (GHD). METHODS: This study included 36 children (mean age, 11.3 ± 1.8 years) who were treated with GH consecutively. Lateral cephalograms were analyzed before and 2 years after start of GH treatment. RESULTS: There were no significant differences in age and sex between ISS and GHD groups and the reference group from semilongitudinal study (10 boys and 8 girls from each group). Before treatment, girls with ISS showed a skeletal Class II facial profile compared with the GHD and reference groups (p = 0.003). During GH treatment, the amount of maxillary length increased beyond norm in the ISS and GHD groups in boys (p = 0.035) > 3 standard deviation score (SDS). Meanwhile, mandibular ramus height (p = 0.001), corpus length, and total mandibular length (p = 0.007 for both) increased more in girls with ISS than in girls with GHD. Lower and total anterior facial heights increased more in girls with ISS than in girls with GHD (p = 0.021 and p = 0.007, respectively), > 7-11 SDS. CONCLUSION: GH should be administered carefully when treating girls with ISS, because GH treatment has great effects on vertical overgrowth of the mandible and can result in longer face.


Asunto(s)
Enanismo Hipofisario/tratamiento farmacológico , Trastornos del Crecimiento/tratamiento farmacológico , Hormona de Crecimiento Humana/administración & dosificación , Mandíbula/crecimiento & desarrollo , Maxilar/crecimiento & desarrollo , Adolescente , Estatura/efectos de los fármacos , Peso Corporal/efectos de los fármacos , Niño , Femenino , Hormona de Crecimiento Humana/efectos adversos , Humanos , Masculino , Mandíbula/efectos de los fármacos , Maxilar/efectos de los fármacos , República de Corea , Caracteres Sexuales
20.
J Comput Chem ; 37(24): 2193-201, 2016 09 15.
Artículo en Inglés | MEDLINE | ID: mdl-27431905

RESUMEN

We investigated the performance of heterogeneous computing with graphics processing units (GPUs) and many integrated core (MIC) with 20 CPU cores (20×CPU). As a practical example toward large scale electronic structure calculations using grid-based methods, we evaluated the Hartree potentials of silver nanoparticles with various sizes (3.1, 3.7, 4.9, 6.1, and 6.9 nm) via a direct integral method supported by the sinc basis set. The so-called work stealing scheduler was used for efficient heterogeneous computing via the balanced dynamic distribution of workloads between all processors on a given architecture without any prior information on their individual performances. 20×CPU + 1GPU was up to ∼1.5 and ∼3.1 times faster than 1GPU and 20×CPU, respectively. 20×CPU + 2GPU was ∼4.3 times faster than 20×CPU. The performance enhancement by CPU + MIC was considerably lower than expected because of the large initialization overhead of MIC, although its theoretical performance is similar with that of CPU + GPU. © 2016 Wiley Periodicals, Inc.

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