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1.
J Craniofac Surg ; 34(5): e517-e520, 2023.
Artículo en Inglés | MEDLINE | ID: mdl-37253249

RESUMEN

Aggressive aspergillosis is a life-threatening fungal infection with rapid progress, mainly affecting the maxillofacial area, especially the nose and paranasal sinuses, in patients with immunocompromised conditions such as diabetes mellitus. Aggressive aspergillosis infection should be differentiated from other invasive fungal sinusitis for early recognition with correct prompt treatment. The main treatment is aggressive surgical debridement such as maxillectomy. Although aggressive debridement should be performed, preservation of the palatal flap should be considered for better postoperative outcomes. In this manuscript, we report the case of a diabetic patient with aggressive aspergillosis affecting the maxilla and paranasal sinuses and describe the appropriate surgical management and prosthodontic rehabilitation.


Asunto(s)
Aspergilosis , Diabetes Mellitus , Micosis , Senos Paranasales , Sinusitis , Humanos , Aspergilosis/complicaciones , Aspergilosis/cirugía , Senos Paranasales/cirugía , Sinusitis/microbiología
2.
J Prosthet Dent ; 130(3): 273-277, 2023 Sep.
Artículo en Inglés | MEDLINE | ID: mdl-35184883

RESUMEN

Acrylic resin denture teeth can wear and chip when opposed by zirconia prostheses. This clinical report describes the use of zirconia complete crowns to prevent these problems. The predictability of treatment was improved by using the computer-aided design and computer-aided manufacturing (CAD-CAM) double-scanning method.


Asunto(s)
Resinas Acrílicas , Coronas , Circonio , Diseño Asistido por Computadora , Dentaduras
3.
BMC Oral Health ; 23(1): 33, 2023 01 20.
Artículo en Inglés | MEDLINE | ID: mdl-36670429

RESUMEN

BACKGROUND: Orthodontic brackets provide a favorable environment for Streptococcus mutans biofilm formation, increasing the risk of white spots and dental caries. Manganese oxide (MnO2) nanozyme-doped diatom microbubbler (DM) is a recently developed material for biofilm removal. DM can generate oxygen by catalase-mimicking activity in Hydrogen peroxide (H2O2) solution and move with ejecting oxygen microbubbles to produce a mechanical self-cleansing effect. This study aimed to evaluate the feasibility of DM as a novel bracket cleaner. METHODS: DM was prepared according to the protocol and analyzed using a scanning electron microscope (SEM). We treated S. mutans biofilms grown over bracket with phosphate-buffered saline (PBS group), 0.12% chlorhexidine (CHX group), 3% H2O2 (H2O2 group), and co-treatment with 3 mg/mL of DM and 3% H2O2 (DM group). The biofilm removal effect was analyzed using crystal violet assay, and the results were observed using SEM. The viability of S. mutans in remaining biofilms was evaluated using confocal laser scanning microscopy (CLSM). Finally, we examined the effect of all materials on mature multispecies biofilms formed on debonded brackets. RESULTS: Crystal violet assay results revealed that the CHX group removed more biofilms than the control group, and the DM group removed biofilms more effectively than the CHX group (p < 0.0001). SEM and CLSM images showed that CHX killed S. mutans but failed to remove most biofilms on brackets. However, DM effectively removed biofilms and mature multispecies biofilms on debonded brackets (p < 0.0001). CONCLUSIONS: Co-treatment with DM and H2O2 is effective in removing biofilms on orthodontic brackets compared to conventional antibacterial agents.


Asunto(s)
Caries Dental , Diatomeas , Soportes Ortodóncicos , Humanos , Peróxido de Hidrógeno/farmacología , Compuestos de Manganeso/farmacología , Óxidos/farmacología , Caries Dental/microbiología , Violeta de Genciana/farmacología , Streptococcus mutans , Biopelículas , Antibacterianos/farmacología
4.
J Prosthet Dent ; 127(2): 331-337, 2022 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-33250197

RESUMEN

STATEMENT OF PROBLEM: A digital quantitative occlusal analyzer with claimed lower cost and easier maneuverability has been introduced to replace conventional methods. However, information regarding its performance is scarce. PURPOSE: The purpose of this in vitro study was to evaluate the reliability and repeatability of a newly introduced digital occlusal analysis device (Accura) and to compare it with an established occlusal analyzer (T-scan Novus). MATERIAL AND METHODS: The sensor films of both devices were positioned between titanium maxillary and mandibular models that were equilibrated and arbitrarily mounted on a semiadjustable articulator. Compressive force was applied to the upper arm of the articulator with a universal testing machine, increased gradually to 50 N, and then released automatically. The time and force measurements from the universal testing machine and the tested devices were recorded by operating software programs. Five articulating film sensors of each device were tested 3 times each by 2 examiners and were repeated on consecutive days, totaling 60 trials per device. Reliability was defined as an agreement between the loaded force and measured force. Repeatability was defined as an agreement between repeated measurements of the Accura and T-scan Novus. Intraclass correlation coefficient was calculated for the statistical analysis (α=.05). RESULTS: The calculated intraclass correlation coefficient of the Accura and the universal testing machine was 0.952. The intraclass correlation coefficient of the T-scan Novus and the universal testing machine was 0.963. Intraclass correlation coefficients that were calculated to compare the data acquired from different days were 0.938 for the Accura and 0.911 for the T-scan Novus. CONCLUSIONS: The experimental results indicated that the reliability of both the Accura and T-scan Novus was excellent for measuring occlusal forces. In addition, both the Accura and T-scan Novus exhibited excellent repeatability.


Asunto(s)
Fuerza de la Mordida , Articuladores Dentales , Maxilar , Reproducibilidad de los Resultados , Programas Informáticos
5.
J Prosthet Dent ; 2022 Jun 10.
Artículo en Inglés | MEDLINE | ID: mdl-35691713

RESUMEN

STATEMENT OF PROBLEM: When scanning implant abutments, an incomplete scan is often obtained because of a subgingival location or restricted accessibility. Whether these problems can be overcome with a novel scanning technique with digital superimposition of the custom abutment is unclear. PURPOSE: The purpose of this in vitro study was to evaluate the effect of the process of superimposing the custom abutment library data onto the scanned abutment data on the accuracy of the digital scan with an intraoral scanner. MATERIAL AND METHODS: A model with a single implant was prepared. The custom abutment of the corresponding implant was produced and was scanned with a laboratory scanner to produce the custom abutment library data. The custom abutment was connected to the implant, and the model was scanned with a laboratory scanner for the reference data. The custom abutment and adjacent teeth were scanned 10 times with an intraoral scanner. Thus, 10 files were saved as the first test group (IOS). After transferring 10 files of the group IOS to a computer-aided design (CAD) software program (exocad DentalCAD), the custom abutment library data were superimposed on the corresponding abutments, and the results were saved as the second test group (S-Exo). For the third test group (S-Den), the same superimposing process was performed as for the group S-Exo but by using another CAD software program (Dental System). The accuracy of the files of the 3 test groups was evaluated by comparing them with the reference file by using a 3D inspection software program. Statistical analysis was performed with 1-way repeated measures ANOVA (α=.05). RESULTS: The RMS of the IOS group decreased significantly from 42.1 ±1.1 µm to 36.37 ±0.74 µm for the S-Exo group and 36.89 ±0.69 µm for the S-Den group after superimposition (P<.05). InTOL increased significantly from 88.17 ±0.75% to 91.57 ±0.56% in the S-Exo group and 91.31 ±0.56% in the S-Den group (P<.05). For the mean 3D discrepancy of all 66 points along the margin and 16 points of interest, the IOS group showed significantly higher discrepancy than the superimposed groups (P<.05), implying that the accuracy of scanned data with the intraoral scanner increased after superimposition with the abutment library data. No significant difference was found according to the type of software program (P>.05). CONCLUSIONS: The process of superimposing the titanium custom abutment with the prescanned custom abutment library data improved the accuracy of a digital scan made with an intraoral scanner.

6.
J Prosthet Dent ; 2022 Mar 01.
Artículo en Inglés | MEDLINE | ID: mdl-35246320

RESUMEN

STATEMENT OF PROBLEM: Duplicating mandibular movement with a semi-adjustable articulator has been reported to lack accuracy. However, although previous studies have analyzed articulator movement, few have compared excursive tooth contact on the articulator with tooth contact during actual mandibular movement. PURPOSE: The purpose of this clinical study was to evaluate the concordance of semi-adjustable articulator contacts with intraoral contacts during eccentric movements by using a T-scan occlusal analysis system. MATERIAL AND METHODS: Forty-two participants with normal occlusion and without signs of temporomandibular disorder were analyzed for the reproducibility of eccentric tooth contact on a semi-adjustable articulator. Maxillary casts made from irreversible hydrocolloid impressions were mounted on a semi-adjustable articulator with the facebow. The condylar inclination of the articulator was set by using interocclusal records. Three recordings of right and left excursive mandibular movement and protrusive mandibular movement were made in the supine position by using the T-scan v9.1. The same procedure was then performed with the articulator. The results of complete mandibular movement from T-scan measurements were divided into 4 time points for analysis: T0, T1, T2, and T3. The concordance of intraoral and articulator occlusal contacts was evaluated at each point, and the occlusal force for each tooth was compared. Overall concordance and concordance of the working and nonworking sides were also calculated. Repeated measures analysis of variance was used to analyze differences between the concordance of intraoral and articulator contacts according to mandibular movement direction, time, and working and nonworking sides (α=.01). RESULTS: For all teeth, concordance between the intraoral and articulator occlusal contacts during excursive mandibular movement was greatest at T0, decreasing at T1 and T2, and increasing at T3. No significant differences were found in the concordance among the right lateral, left lateral, and protrusive excursion (P>.01). The concordance of working side occlusal contacts during lateral excursion was significantly lower at T3 than that at T0 (P<.01). CONCLUSIONS: When comparing intraoral and articulator contacts during lateral eccentric mandibular movement, concordance was affected by time and working or nonworking side. Reproducibility of initial eccentric tooth contact on a semi-adjustable articulator appeared to be reliable. However, occlusal adjustment of the working side might be required after prosthesis delivery.

7.
J Prosthet Dent ; 127(5): 784.e1-784.e7, 2022 May.
Artículo en Inglés | MEDLINE | ID: mdl-35221037

RESUMEN

STATEMENT OF PROBLEM: Although 3-dimensional (3D)-printed resin prostheses are widely used, studies on the effects of the manufacturing parameters of 3D printing on the color stability and stainability of these prostheses are lacking. PURPOSE: The purpose of this in vitro study was to investigate the effects of layer thickness and printing orientation on the color stability and stainability of a 3D-printed resin. In addition, the influence of roughness and water contact angle was evaluated. MATERIAL AND METHODS: Color changes (ΔE00) in tooth-colored resin specimens produced by 3D printing with 2 different layer thicknesses and 3 different printing orientations and immersed in 3 types of aging media (distilled water, coffee solution, and wine) were evaluated (n=10). The CIELab color values were measured with a spectrophotometer at baseline and different time points (1, 3, 7, 15, and 30 days). The surface roughness (Ra) of resin specimens was measured at various time points (baseline, 7, 15, and 30 days) by confocal laser scanning microscopy after immersion in coffee solution (n=15). The water contact angle was determined by using the sessile drop method (n=10). The ΔE00 values were analyzed by using the 3-way repeated measures ANOVA followed by the Bonferroni test and Dunnett T3 test (α=.05). Ra values were analyzed by 3-way repeated measures ANOVA (α=.05). The water contact angle data were analyzed by 2-way ANOVA (α=.05). RESULTS: The 3-way repeated measures ANOVA showed that layer thickness, printing orientation, and storage time significantly influenced the ΔE00 values of the 3D-printed resin specimens in each aging medium (P<.001). The ΔE00 values in the 0-degree subgroups were significantly lower than those in the 45- and 90-degree subgroups (P<.05). The ΔE00 values in the 25-µm thick groups were significantly higher than those in the 100-µm thick groups (P<.05). The ΔE00 values demonstrated an increase up to 15 days in all aging media. In distilled water, the ΔE00 values of the specimens increased or decreased depending on the groups, whereas in the coffee solution, the values decreased after 15 days (P<.001); in red wine, the values demonstrated a continuous increase up to 30 days in all groups (P<.001). The 3-way repeated measures ANOVA showed that the Ra values did not change significantly with immersion time (P=.444). The 2-way ANOVA showed that the water contact angle was not significantly affected by layer thickness (P=.921) or printing orientation (P=.062). CONCLUSIONS: Layer thickness and printing orientation affected the color stability and stainability of the 3D-printed resin. The discoloration of the 3D-printed resin differed with time, depending on the type of aging media used.


Asunto(s)
Café , Resinas Compuestas , Color , Ensayo de Materiales , Impresión Tridimensional , Propiedades de Superficie , Agua
8.
Int J Mol Sci ; 22(10)2021 May 11.
Artículo en Inglés | MEDLINE | ID: mdl-34064719

RESUMEN

Inflammation is a major cause of several chronic diseases and is reported to be recovered by the immuno-modulation of mesenchymal stem cells (MSCs). While most studies have focussed on the anti-inflammatory roles of MSCs in stem cell therapy, the impaired features of MSCs, such as the loss of homeostasis by systemic aging or pathologic conditions, remain incompletely understood. In this study, we investigated whether the altered phenotypes of human placenta-derived MSCs (hPD-MSCs) exposed to inflammatory cytokines, including TNF-α and IFN-γ, could be protected by MIT-001, a small anti-inflammatory and anti-necrotic molecule. MIT-001 promoted the spindle-like shape and cytoskeletal organization extending across the long cell axis, whereas hPD-MSCs exposed to TNF-α/IFN-γ exhibited increased morphological heterogeneity with an abnormal cell shape and cytoskeletal disorganization. Importantly, MIT-001 improved mitochondrial distribution across the cytoplasm. MIT-001 significantly reduced basal respiration, ATP production, and cellular ROS levels and augmented the spare respiratory capacity compared to TNF-α/IFN-γ-exposed hPD-MSCs, indicating enhanced mitochondrial quiescence and homeostasis. In conclusion, while TNF-α/IFN-γ-exposed MSCs lost homeostasis and mitochondrial quiescence by becoming over-activated in response to inflammatory cytokines, MIT-001 was able to rescue mitochondrial features and cellular phenotypes. Therefore, MIT-001 has therapeutic potential for clinical applications to treat mitochondrion-related inflammatory diseases.


Asunto(s)
Citoesqueleto/fisiología , Células Madre Mesenquimatosas/fisiología , Mitocondrias/fisiología , Compuestos Orgánicos/farmacología , Placenta/citología , Citoesqueleto/efectos de los fármacos , Femenino , Humanos , Células Madre Mesenquimatosas/citología , Células Madre Mesenquimatosas/efectos de los fármacos , Mitocondrias/efectos de los fármacos , Consumo de Oxígeno , Placenta/efectos de los fármacos , Placenta/metabolismo , Embarazo , Especies Reactivas de Oxígeno/metabolismo
9.
Chem Rev ; 118(4): 1664-1690, 2018 02 28.
Artículo en Inglés | MEDLINE | ID: mdl-29336552

RESUMEN

Biological cells are complex living machines that have garnered significant attention for their potential to serve as a new generation of therapeutic and delivery agents. Because of their secretion, differentiation, and homing activities, therapeutic cells have tremendous potential to treat or even cure various diseases and injuries that have defied conventional therapeutic strategies. Therapeutic cells can be systemically or locally transplanted. In addition, with their ability to express receptors that bind specific tissue markers, cells are being studied as nano- or microsized drug carriers capable of targeted transport. Depending on the therapeutic targets, these cells may be clustered to promote intercellular adhesion. Despite some impressive results with preclinical studies, there remain several obstacles to their broader development, such as a limited ability to control their transport, engraftment, secretion and to track them in vivo. Additionally, creating a particular spatial organization of therapeutic cells remains difficult. Efforts have recently emerged to resolve these challenges by engineering cell surfaces with a myriad of bioactive molecules, nanoparticles, and microparticles that, in turn, improve the therapeutic efficacy of cells. This review article assesses the various technologies developed to engineer the cell surfaces. The review ends with future considerations that should be taken into account to further advance the quality of cell surface engineering.


Asunto(s)
Tratamiento Basado en Trasplante de Células y Tejidos , Animales , Bioingeniería , Rastreo Celular , Propiedades de Superficie
10.
Arch Gynecol Obstet ; 300(4): 975-980, 2019 10.
Artículo en Inglés | MEDLINE | ID: mdl-31440822

RESUMEN

PURPOSE: This study aimed to present cases involving in vitro fertilization (IVF) cycles in patients with stage IA endometrial adenocarcinoma (EC) who underwent fertility-sparing conservative treatment. METHODS: Twenty-two patients who underwent IVF cycles in a single fertility center between May 2005 and February 2017 after progestin treatment for stage IA EC were chosen for this study. Outcomes of IVF cycles were analyzed retrospectively. RESULTS: Women of a median age of 34 years (range 26-41 years) underwent a total of 49 embryo transfers within an average of 2 months after their last progestin treatment. The clinical pregnancy rate per transfer was 26.5%, implantation rate was 16.7%, and live birth rate was 14.3%. The cumulative clinical pregnancy rate was 50% (11/22), resulting in 6 live births (27.3%) within 3 cycles of embryo transfer. The median endometrial thickness on the day of human chorionic gonadotropin injection in 34 fresh cycles was 9.0 mm (range 4-10 mm) in live births, 7.5 mm (range 6-9 mm) in miscarriages, and 6.0 mm (range 4-15 mm) in no pregnancy cases. During a median post-cancer treatment follow-up period of 41 months (range 9-150 months), 6 (27.3%) women underwent definitive hysterectomy for EC relapse. CONCLUSIONS: This study showed an acceptable cumulative pregnancy rate after the IVF procedure in patients with early-stage EC who were treated conservatively. Considering the high relapse rate, it is of great importance that these patients are closely monitored after the IVF cycles.


Asunto(s)
Preservación de la Fertilidad , Fertilización In Vitro , Aborto Espontáneo , Adulto , Tasa de Natalidad , Implantación del Embrión , Transferencia de Embrión/métodos , Neoplasias Endometriales/tratamiento farmacológico , Femenino , Humanos , Nacimiento Vivo , Recurrencia Local de Neoplasia/epidemiología , Embarazo , Índice de Embarazo , Estudios Retrospectivos
11.
J Assist Reprod Genet ; 35(9): 1623-1630, 2018 Sep.
Artículo en Inglés | MEDLINE | ID: mdl-30006788

RESUMEN

PURPOSE: The aim of this study is to analyze women's opinions and their decision making processes regarding elective oocyte cryopreservation (OC). METHODS: One hundred twenty-four women who had elective OC counseling at the CHA Seoul Fertility Center were asked to complete a survey after their first visit. Data collection regarding age, marital status, monthly income, occupation, religion, reproductive history, questions about the participant's view on their own fecundity, and future parenthood were included. The modified Reproductive Concerns After Cancer scale and the Decisional Conflict Scale were used for analysis. RESULTS: The participants' mean age was 37.1 ± 4.8 years old. Eighty-six percent of the participants had regular periods. Ninety-two percent thought it was important to have their own biological offspring, and 86% were willing to pursue OC. Forty-nine percent appeared to have high DCS scores regarding making a decision of OC. Sixty-eight percent pursued OC, and the mean number of oocytes cryopreserved per patient was 10.5 ± 8.3. Multivariate analysis revealed that age was the only factor associated with high DCS scores (P = 0.002). Feeling less fertile than other women of same age and low DCS scores were the factors associated with pursuing OC (P = 0.02 and 0.004, respectively) after adjusting for possible confounding factors, including age. CONCLUSIONS: Older women had more difficulties in making decisions about OC. Adjusting for age, women who thought that they were less fertile than other women of same age and those with lower decisional conflict were more likely to pursue OC. Further studies should focus on the validation of older women's decisional conflicts regarding OC.


Asunto(s)
Criopreservación/métodos , Toma de Decisiones , Preservación de la Fertilidad/métodos , Oocitos/crecimiento & desarrollo , Adolescente , Adulto , Anciano , Consejo , Femenino , Fertilidad/fisiología , Humanos , Encuestas y Cuestionarios
12.
Arch Gynecol Obstet ; 297(3): 791-796, 2018 03.
Artículo en Inglés | MEDLINE | ID: mdl-29264647

RESUMEN

PURPOSE: Supplementation of growth hormone (GH) during controlled ovarian stimulation (COS) has been suggested to improve ovarian response. Despite potential benefits in poor responders, multiple injections of GH during COS are inconvenient. We conducted a randomized controlled study to evaluate the efficacy and safety of sustained-release human GH in poor responders undergoing in vitro fertilization (IVF). METHODS: This was a single-center, randomized, open-label, parallel study. Infertile women who satisfied the Bologna criteria for poor responders were randomized into GH treatment and control groups. The treatment group received a sustained-release GH (Eutropin Plus® 20 mg) three times before and during COS (mid-luteal, late luteal, and menstrual cycle day 2). The baseline characteristics and IVF outcomes were compared between the two groups. RESULTS: A total of 127 patients were included in the analysis. The mean age was 39.6 years and mean anti-Müllerian hormone level was 0.6 ng/ml. There was no significant difference in the baseline characteristics between GH treatment and control groups. The number of follicles on the human chorionic gonadotropin triggering day (3.1 ± 2.3 vs. 2.4 ± 1.6, P = 0.043) and the proportion of metaphase II oocytes (67.5 vs. 52.3%, P = 0.030) were higher in the GH group than in controls. The percentage of clinical and ongoing pregnancy and miscarriage was not different between the two groups. CONCLUSION: Supplementation of sustained-release GH before and during COS improved ovarian response, with an increase in mature oocytes in poor responders. Further studies are needed to ensure this benefit in general infertility patients.


Asunto(s)
Gonadotropina Coriónica , Transferencia de Embrión/métodos , Fertilización In Vitro/métodos , Hormona del Crecimiento/uso terapéutico , Oocitos/metabolismo , Inducción de la Ovulación/métodos , Adulto , Hormona Antimülleriana , Preparaciones de Acción Retardada , Implantación del Embrión/efectos de los fármacos , Femenino , Hormona del Crecimiento/administración & dosificación , Humanos , Infertilidad Femenina/tratamiento farmacológico , Embarazo , Índice de Embarazo , Estudios Prospectivos , Resultado del Tratamiento
13.
Phytother Res ; 31(11): 1795-1804, 2017 Nov.
Artículo en Inglés | MEDLINE | ID: mdl-28921708

RESUMEN

Scopoletin is a bioactive component in many edible plants and fruits. This study investigated the effects of scopoletin on hepatic steatosis and inflammation in a high-fat diet fed type 1 diabetic mice by comparison with metformin. Scopoletin (0.01%, w/w) or metformin (0.5%, w/w) was provided with a high-fat diet to streptozotocin-induced diabetic mice for 11 weeks. Both scopoletin and metformin lowered blood glucose and HbA1c , serum ALT, TNF-α and IL-6 levels, glucose intolerance, and hepatic lipid accumulation compared with the diabetic control group. Scopoletin or metformin down-regulated hepatic gene expression of triglyceride (Pparg, Plpp2, and Dgat2) and cholesterol (Hmgcr) synthesis as well as inflammation (Tlr4, Myd88, Nfkb1, Tnfa, and Il6), while it up-regulated Cyp7a1 gene. Hepatic PPARγ and DGAT2 protein levels were also down-regulated in scopoletin or metformin group compared with the control group. Scopoletin or metformin also inhibited hepatic fatty acid synthase and phosphatidate phosphohydrolase activities. These results suggest that scopoletin protects against diabetes-induced steatosis and inflammation by inhibiting lipid biosynthesis and TLR4-MyD88 pathways. Copyright © 2017 John Wiley & Sons, Ltd.


Asunto(s)
Diabetes Mellitus Experimental/tratamiento farmacológico , Hígado Graso/tratamiento farmacológico , Inflamación/tratamiento farmacológico , Escopoletina/farmacología , Animales , Glucemia/efectos de los fármacos , Colesterol/sangre , Diabetes Mellitus Experimental/inducido químicamente , Dieta Alta en Grasa , Suplementos Dietéticos , Hígado Graso/sangre , Intolerancia a la Glucosa , Hemoglobinas/análisis , Interleucina-6/sangre , Hígado/efectos de los fármacos , Masculino , Metformina/farmacología , Ratones , Ratones Endogámicos C57BL , Factor 88 de Diferenciación Mieloide/metabolismo , Receptor Toll-Like 4/metabolismo , Triglicéridos/sangre , Factor de Necrosis Tumoral alfa/sangre
14.
J Prosthet Dent ; 117(4): 532-538, 2017 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-27847157

RESUMEN

STATEMENT OF PROBLEM: A simplified mounting technique that adopts an average condylar guidance has been advocated. Despite this, the experimental explanation of how average settings differ from individual condylar guidance remains unclear. PURPOSE: The purpose of this in vitro study was to examine potential occlusal error by using average condylar guidance settings during nonworking side movement of the articulator. MATERIAL AND METHODS: Three-dimensional positions of the nonworking side maxillary first molar at various condylar and incisal settings were traced using a laser displacement sensor attached to the motorized stages with biaxial freedom of movement. To examine clinically relevant occlusal consequences of condylar guidance setting errors, the vertical occlusal error was defined as the vertical-axis positional difference between the average setting trace and the other condylar guidance setting trace. In addition, the respective contribution of the condylar and incisal guidance to the position of the maxillary first molar area was analyzed by multiple regression analysis using the resultant coordinate data. RESULTS: Alteration from individual to average settings led to a positional difference in the maxillary first molar nonworking side movement. When the individual setting was lower than average, vertical occlusal error occurred, which might cause occlusal interference. The vertical occlusal error ranged from -2964 to 1711 µm. In addition, the occlusal effect of incisal guidance was measured as a partial regression coefficient of 0.882, which exceeded the effect of condylar guidance, 0.431. CONCLUSIONS: Potential occlusal error as a result of adopting an average condylar guidance setting was observed. The occlusal effect of incisal guidance doubled the effect of condylar guidance.


Asunto(s)
Oclusión Dental , Cóndilo Mandibular/anatomía & histología , Articuladores Dentales , Humanos , Técnicas In Vitro , Maxilar/anatomía & histología , Diente Molar/anatomía & histología , Dimensión Vertical
15.
J Prosthet Dent ; 117(6): 735-742, 2017 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-27914668

RESUMEN

STATEMENT OF PROBLEM: Whether the implant abutment in implant-assisted removable partial dentures (IARPDs) functions as a natural removable partial denture (RPD) tooth abutment is unknown. PURPOSE: The purpose of this 3-dimensional finite element study was to analyze the biomechanical behavior of implant crown, bone, RPD, and IARPD. MATERIAL AND METHODS: Finite element models of the partial maxilla, teeth, and prostheses were generated on the basis of a patient's computed tomographic data. The teeth, surveyed crowns, and RPDs were created in the model. With the generated components, four 3-dimensional finite element models of the partial maxilla were constructed: tooth-supported RPD (TB), implant-supported RPD (IB), tooth-tissue-supported RPD (TT), and implant-tissue-supported RPD (IT) models. Oblique loading of 300 N was applied on the crowns and denture teeth. The von Mises stress and displacement of the denture abutment tooth and implant system were identified. RESULTS: The highest von Mises stress values of both IARPDs occurred on the implants, while those of both natural tooth RPDs occurred on the frameworks of the RPDs. The highest von Mises stress of model IT was about twice that of model IB, while the value of model TT was similar to that of model TB. The maximum displacement was greater in models TB and TT than in models IB and IT. Among the 4 models, the highest maximum displacement value was observed in the model TT and the lowest value was in the model IB. CONCLUSIONS: Finite element analysis revealed that the stress distribution pattern of the IARPDs was different from that of the natural tooth RPDs and the stress distribution of implant-supported RPD was different from that of implant-tissue-supported RPD. When implants are used for RPD abutments, more consideration concerning the RPD design and the number or location of the implant is necessary.


Asunto(s)
Prótesis Dental de Soporte Implantado , Dentadura Parcial Removible , Fenómenos Biomecánicos , Coronas , Pilares Dentales , Diseño de Implante Dental-Pilar , Análisis del Estrés Dental , Análisis de Elementos Finitos , Humanos , Imagenología Tridimensional
16.
Bioorg Med Chem Lett ; 26(19): 4655-4660, 2016 10 01.
Artículo en Inglés | MEDLINE | ID: mdl-27575482

RESUMEN

Peucedanum japonicum Thunb is a medicinal plant belonging to the family Umbelliferae. This study evaluated the anti-diabetic and anti-obesity effects of cis-3',4'-diisovalerylkhellactone (cDIVK) isolated from Peucedanum japonicum Thunb leaves. cDIVK (30 and 50µM) effectively inhibited adipocyte differentiation and fat accumulation, whereas it stimulated glucose uptake compared with the control in 3T3-L1 cells. cDIVK significantly increased AMPK activation and suppressed protein and mRNA expression of major adipogenic transcriptional factors such as C/EBPα, PPARγ and SREBP-1c in 3T3-L1 cells. In addition, cDIVK had potential α-glucosidase inhibitory activity. These results indicated that cDIVK may act as a natural dual therapeutic agent for diabetes and obesity.


Asunto(s)
Fármacos Antiobesidad/farmacología , Apiaceae/química , Cumarinas/farmacología , Hipoglucemiantes/farmacología , Hojas de la Planta/química , Células 3T3-L1 , Adipocitos/efectos de los fármacos , Animales , Espectroscopía de Resonancia Magnética con Carbono-13 , Diferenciación Celular/efectos de los fármacos , Cromatografía Líquida de Alta Presión , Ratones , Espectroscopía de Protones por Resonancia Magnética , Espectrofotometría Ultravioleta
17.
Implant Dent ; 23(5): 529-33, 2014 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-25192155

RESUMEN

PURPOSE: The purpose of this study was to investigate in vivo histomorphometric differences in initial bone response to modified sand-blasted, large-grit, acid-etched (modSLA), and fluoride-modified (F-mod) implant surfaces in rabbit tibia models. MATERIALS AND METHODS: Field emission scanning electron microscopy (FE-SEM), confocal laser scanning microscopy (CLSM), and x-ray photoelectron spectroscopy (XPS) were used to determine surface characteristics. Each of 3 live New Zealand white rabbits received an F-mod implant in one tibia and a modSLA implant in the other. After 1 week, the rabbits were killed, and the undecalcified histologic slides were prepared. Bone-to-implant contact (BIC) ratio and bone area (BA) were calculated in a defined area under a light microscope. RESULTS: FE-SEM, CLSM, and XPS showed that the modSLA surface was significantly rougher than the F-mod, and that the F-mod surface had a very small amount of fluoride. However, despite these surface variances, histomorphometric analyses revealed no significant differences in either BIC or BA. CONCLUSIONS: Our results suggest that the in vivo effects of increased hydrophilicity, when added to a titanium dental implant surface, on early bone response may be similar to the effects of surface fluoride treatment.


Asunto(s)
Implantes Dentales , Fluoruros/química , Oseointegración , Titanio/química , Animales , Interacciones Hidrofóbicas e Hidrofílicas , Conejos , Propiedades de Superficie
18.
Indian J Exp Biol ; 52(7): 683-91, 2014 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-25059036

RESUMEN

Ursolic acid (UA) is a pentacyclic triterpenoid compound that naturally occurs in fruits, leaves and flowers of medicinal herbs. This study investigated the dose-response efficacy of UA (0.01 and 0.05%) on glucose metabolism, the polyol pathway and dyslipidemia in streptozotocin/nicotinamide-induced diabetic mice. Supplement with both UA doses reduced fasting blood glucose and plasma triglyceride levels in non-obese type 2 diabetic mice. High-dose UA significantly lowered plasma free fatty acid, total cholesterol and VLDL-cholesterol levels compared with the diabetic control mice, while LDL-cholesterol levels were reduced with both doses. UA supplement effectively decreased hepatic glucose-6-phosphatase activity and increased glucokinase activity, the glucokinase/glucose-6-phosphatase ratio, GLUT2 mRNA levels and glycogen content compared with the diabetic control mice. UA supplement attenuated hyperglycemia-induced renal hypertrophy and histological changes. Renal aldose reductase activity was higher, whereas sorbitol dehydrogenase activity was lower in the diabetic control group than in the non-diabetic group. However, UA supplement reversed the biochemical changes in polyol pathway to normal values. These results demonstrated that low-dose UA had preventive potency for diabetic renal complications, which could be mediated by changes in hepatic glucose metabolism and the renal polyol pathway. High-dose UA was more effective anti-dyslipidemia therapy in non-obese type 2 diabetic mice.


Asunto(s)
Diabetes Mellitus Experimental/tratamiento farmacológico , Diabetes Mellitus Tipo 2/tratamiento farmacológico , Dislipidemias/tratamiento farmacológico , Glucosa/metabolismo , Polímeros/metabolismo , Transducción de Señal/efectos de los fármacos , Triterpenos/farmacología , Animales , Antineoplásicos Fitogénicos/farmacología , Western Blotting , Complicaciones de la Diabetes/etiología , Complicaciones de la Diabetes/patología , Complicaciones de la Diabetes/prevención & control , Diabetes Mellitus Experimental/complicaciones , Diabetes Mellitus Experimental/metabolismo , Diabetes Mellitus Tipo 2/complicaciones , Diabetes Mellitus Tipo 2/metabolismo , Dislipidemias/etiología , Dislipidemias/patología , Glucoquinasa/metabolismo , Transportador de Glucosa de Tipo 2/genética , Glucosa-6-Fosfatasa/metabolismo , Glucógeno/metabolismo , Hiperglucemia/complicaciones , Enfermedades Renales/etiología , Enfermedades Renales/patología , Enfermedades Renales/prevención & control , Masculino , Ratones , Ratones Endogámicos ICR , Ratones Endogámicos NOD , ARN Mensajero/genética , Reacción en Cadena en Tiempo Real de la Polimerasa , Reacción en Cadena de la Polimerasa de Transcriptasa Inversa , Ácido Ursólico
19.
Maxillofac Plast Reconstr Surg ; 46(1): 17, 2024 May 10.
Artículo en Inglés | MEDLINE | ID: mdl-38727979

RESUMEN

BACKGROUND: Immediate implant placement has gained popularity due to its several advantages. However, immediate placement has its challenges, including concerns about primary stability and bone formation around the implant. The aim of the present study is to evaluate the clinical outcomes of tapered, sand-blasted, and acid-etched internal submerged dental implants in various regions of the jaw bones and to provide a positional rationale for immediate implant placement. METHODS: Between 2009 and 2018, a single surgeon at Seoul National University Dental Hospital in Seoul, Korea, immediately inserted 49 dental implants with tapered bone-level design after extraction, in a total of 34 patients. The clinical outcomes were collected and evaluated, focusing on location of implant placement and marginal bone loss (MBL), with consideration of other parameters such as implant diameter and length. RESULTS: Of 49 immediately installed Luna® (Shinhung Co., Seoul, Korea) dental implants, 23 were placed in the mandible, and 26 were set in the maxilla. The mean age of patients at the time of installation was 65.91 years, ranging from 40 to 86 years. The average follow-up period was 7.43 years, with a range of 5 to 14 years. After a 5-year retrospective evaluation of tapered, sand-blasted, and acid-etched internal submerged dental implants for immediate implant placement, the cumulative survival rate was 93.88%, with 100% survival rate in the mandible and premolar region of both the maxilla and mandible. CONCLUSIONS: After a 5-year evaluation, tapered, sand-blasted, and acid-etched internal submerged dental implants demonstrated good efficacy for immediate placement in various locations within the dental arches, exhibiting effective clinical performance.

20.
Bioengineering (Basel) ; 11(3)2024 Mar 12.
Artículo en Inglés | MEDLINE | ID: mdl-38534546

RESUMEN

Narrow-diameter implants (NDI) serve as a solution for treating limited bone volume in the anterior mandible. This study aimed to evaluate the one-year clinical outcomes of various NDIs in the mandibular incisor area after immediate loading in partially edentulous patients. This single-center, prospective, single-blinded, randomized controlled trial study included 21 patients, with 7 patients in each of the following groups: control (BLT NC SLActive®; Straumann), experimental group 1 (CMI IS-III Active® S-Narrow; Neobiotech), and experimental group 2 (CMI IS-III Active® Narrow; Neobiotech). Using full digital flow, two fixtures were placed in each patient and immediately provisionalized on the day of surgery. Evaluations encompassed periapical radiographs, implant stability quotient (ISQ), implant stability test (IST) readings, per-implant soft tissue health, patient satisfaction surveys, and esthetic score assessments. Definitive prostheses were delivered twelve weeks post-surgery (CRiS, number: KCT0007300). Following exclusions due to low stability values (n = 2), fixture failure (n = 5), and voluntary withdrawal (n = 1), the implant success rate for patients completing all clinical protocols stood at 100%. The resulting patient failure rates in the control, experimental group 1, and experimental group 2 were 50.0%, 42.9%, and 14.3%, respectively. There were no significant differences between the groups in terms of marginal bone loss, soft tissue health, patient satisfaction, and esthetic scores. Narrow implants showed superior clinical outcomes, followed by S-Narrow and Straumann implants. Calculated one-year survival rates at the implant level were 66.7% for the control group, 85.7% for experimental group 1, and 100% for experimental group 2. All three types of NDIs showed acceptable clinical and radiographic results during the year-long observation period.

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