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1.
Ann Dermatol ; 36(2): 81-90, 2024 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-38576246

RESUMEN

BACKGROUND: Daily usage of facial masks during coronavirus disease 2019 pandemic influenced on facial dermatoses. OBJECTIVE: This study investigated the impact of mask-wearing habits on facial dermatoses. METHODS: A nationwide, observational, questionnaire-based survey was conducted from July through August 2021, involving 20 hospitals in Korea. RESULTS: Among 1,958 facial dermatoses, 75.9% of patients experienced aggravation or development of new-onset facial dermatoses after wearing masks. In aggravated or newly developed acne patients (543 out of 743), associated factors were healthcare provider, female gender, and a long duration of mask-wearing. Irritating symptoms, xerosis, and hyperpigmentation were more frequently observed in this group. Aggravated or newly developed rosacea patients (515 out of 660) were likely to be female, young, and have a long duration of mask-wearing per day. Seborrheic dermatitis patients who experienced aggravation or de novo development (132 out of 184) were younger, and they more frequently involved the chin and jaw in addition to the nasolabial folds and both cheeks. Contact dermatitis patients (132 out of 147) with aggravation or de novo development tended to be female, involve both cheeks, and complain of pruritus. Aggravated or newly developed atopic dermatitis patients (165 out of 224) were more likely to be female, and had a higher baseline investigator global assessment score before mask-wearing. CONCLUSION: Clinical features and factors related to aggravation were different according to the types of facial dermatoses.

2.
Artículo en Inglés | MEDLINE | ID: mdl-38687283

RESUMEN

BACKGROUND: Trials and real-life studies demonstrated clinically meaningful improvements of disease activity in the majority of patients with moderate to severe atopic dermatitis (AD) treated with the anti-IL-4RA-antibody dupilumab. However, misdiagnosis or confounding skin diseases in particular cutaneous T-cell lymphoma (CTCL) may lead to inadequate response. OBJECTIVE: To investigate the clinical and pathological features of patients with AD who showed insufficient response to dupilumab. METHODS: We reviewed the medical records of 371 patients treated with dupilumab for severe AD. Insufficient response was defined as failure to achieve an improvement of the eczema area severity index (EASI) of at least 50% (EASI-50) at Week 16 and of 75% (EASI-75) at Week 52. Among 46 patients with insufficient response, 35 patients consented to a re-evaluation including a full physical exam, biopsies and laboratory assessments including immunohistochemistry and T-cell receptor gene rearrangement analysis to differentiate CTCL. RESULTS: Of the 371 patients treated with dupilumab, 46 (12.3%) patients showed insufficient response to dupilumab. Of these, 35 underwent further evaluation, and 19 (54.2% of inadequate responders) were finally diagnosed with mycosis fungoides (MF). In these patients, transition to or addition of conventional MF treatment led to clinical improvements. CONCLUSION: Insufficient response to dupilumab treatment may help uncover early MF on an existing AD background.

3.
Ann Dermatol ; 36(1): 35-43, 2024 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-38325432

RESUMEN

BACKGROUND: More than half of acne patients have truncal acne on their chest, back, and shoulders. However, since most studies on acne have focused on the face, data on clinical characteristics and proper management for truncal acne are insufficient. OBJECTIVE: To establish a Korean Acne Rosacea Society (KARS) consensus for experts' perception and treatment patterns of truncal acne. METHODS: We conducted two rounds of the Dephi technique to gather expert opinion and reach a consensus on truncal acne. The first round comprised 48 questionnaires focusing on various aspects such as epidemiology, clinical features, diagnosis, treatment, prognosis and more, while second rounds consisted of 26 questionnaires. RESULTS: A total of 36 dermatologists (36/38 KARS members, 94.7%) completed this survey. In the first-round survey, consensus was reached on 20 out of the 48 questions (41.7%). In the second-round questionnaire, consensus was achieved on 9 of the 26 questions (34.6%). The most unresponsive lesion to truncal acne treatment was scars (atrophic/hypertrophic). The most commonly used treatments for each non-inflammatory and inflammatory truncal acne lesions were selected to use topical retinoids (78.1% of the responders) and oral antibiotics (93.8% of the responders). CONCLUSION: Our study has yielded valuable insights into the epidemiology, clinical manifestations, diagnosis, treatment, and quality of life of patients with truncal acne. We anticipate that this study will inspire further comprehensive research for individuals with truncal acne.

4.
Ann Dermatol ; 35(6): 439-450, 2023 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-38086358

RESUMEN

BACKGROUND: Melanoma is one of the most aggressive and metastatic skin cancers. Although overexpression of Dock180 and Elmo1 has been identified in various cancers, including glioma, ovarian cancer, and breast cancer, their expression and functions in melanoma remain unknown. OBJECTIVE: This study aims to confirm the expression of Dock180 and Elmo1, their underlying mechanisms, and roles in melanoma. METHODS: Both immunohistochemical staining and Western blotting were used to confirm expression of Dock180 and Elmo1 in human melanoma. To identify roles of Dock180 and Elmo1 in cell survival, apoptosis and migration, downregulation of Dock180 or Elmo1 in melanoma cells with small interfering RNA (siRNA) was performed. RESULTS: We identified overexpression of Dock180 and Elmo1 in human melanoma compared to normal skin ex vivo. Inhibition of Dock180 or Elmo1 following siRNA in melanoma cells reduced cell viability and increased apoptosis as supported by increased proportion of cells with Annexin V-PE (+) staining and sub-G0/G1 peak in cell cycle analysis. Moreover, inhibition of Dock180 or Elmo1 regulated apoptosis-related proteins, showing downregulation of Bcl-2, caspase-3, and PARP and upregulation of Bax, PUMA, cleaved caspase-3, and cleaved PARP. Furthermore, knockdown of Dock180 and Elmo1 in melanoma cells reduced cell migration and changed cellular signaling pathways including ERK and AKT. Vemurafenib decreased cell viability in concentration-dependent manner, while transfection with Dock180- or Elmo1-specific siRNA in melanoma cells significantly reduced cell viability. CONCLUSION: Our results suggest that both Dock180 and Elmo1 may be associated with cancer progression, and can be potential targets for treatment of melanoma.

7.
J Dent ; 139: 104746, 2023 12.
Artículo en Inglés | MEDLINE | ID: mdl-37863174

RESUMEN

OBJECTIVES: This study assessed the changes in color stability and biocompatibility of computer-aided design and computer-aided manufacturing (CAD-CAM) glass-ceramics after ultraviolet weathering (UW) aging. METHODS: A total of 300 plate-shaped specimens (12.0 × 14.0 × 1.5 mm3) were prepared using a leucite-reinforced glass-ceramic (IPS Empress CAD; E), a lithium disilicate (IPS e.max CAD; M), and two zirconia-reinforced lithium silicate (Celtra Duo; C, Vita Suprinity; V) glass-ceramics. Specimens were divided into three groups (n = 25, each), subjected to water storage at 37 °C for 24 h (control group), or UW aging at 150 kJ/m2 (first-aged group) or 300 kJ/m2 (second-aged group). The color stability, mechanical and surface properties, and biocompatibility of the CAD-CAM glass-ceramics were investigated experimentally, followed by statistical analysis. RESULTS: The brightness and redness or greenness were reduced in all groups after aging. After the first aging, V exhibited the largest color change and E exhibited the smallest color change. After the second aging, E exhibited the highest nanoindentation hardness and Young's modulus. The surface roughness was the highest for V after the first aging. Furthermore, the hydrophilicity of the materials increased after aging process. The cell proliferation/viability of human gingival fibroblasts was the highest in E before and after aging. Almost all cells survived for all groups based on a live/dead assay. CONCLUSIONS: Leucite-reinforced glass-ceramic exhibit the highest color stability and biocompatibility after aging. The color stability and biocompatibility of CAD-CAM glass-ceramics depend on the aging process and material type. CLINICAL SIGNIFICANCE: Various CAD-CAM glass-ceramics exhibit adequate color stability after UW aging. The leucite-reinforced glass-ceramics exhibit the highest color stability, cell proliferation, and viability after aging. The color stability, mechanical and surface properties, and biocompatibility of the glass-ceramics depend on the aging process and material type.


Asunto(s)
Cerámica , Porcelana Dental , Humanos , Anciano , Silicatos de Aluminio , Propiedades de Superficie , Diseño Asistido por Computadora , Ensayo de Materiales
8.
Pharmaceutics ; 15(8)2023 Aug 10.
Artículo en Inglés | MEDLINE | ID: mdl-37631336

RESUMEN

The purpose of this study is to evaluate the changes in physical properties and biocompatibilities caused by thermocycling of CAD/CAM restorative materials (lithium disilicate, zirconia reinforced lithium silicate, polymer-infiltrated ceramic network, resin nanoceramic, highly translucent zirconia). A total of 225 specimens were prepared (12.0 × 10.0 × 1.5 mm) and divided into three groups subjected to water storage at 37 °C for 24 h (control group), 10,000 cycles in distilled water at 5-55 °C (first aged group), and 22,000 cycles in distilled water at 5-55 °C (second aged group) [(n= 15, each]). The nanoindentation hardness and Young's modulus (nanoindenter), surface roughness (atomic force microscopy (AFM)), surface texture (scanning electron microscopy (FE-SEM)), elemental concentration (energy dispersive spectroscopy (EDS)) and contact angle were evaluated. The morphology, proliferation and adhesion of cultured human gingival fibroblasts (HGFs) were analyzed. The data were analyzed using one-way ANOVA and Tukey's test (p < 0.05). The results showed that the nanoindentation hardness and Young's modulus were decreased after thermocycling aging. Cell viability and proliferation of the material decreased with aging except for the highly translucent zirconia. Zirconia-reinforced lithium silicate exhibited significantly lower cell viability compared to other materials. The surface roughnesses of all groups increased with aging. Cell viability and Cell adhesion were influenced by various factors, including the surface chemical composition, hydrophilicity, surface roughness, and topography.

9.
J Clin Med ; 12(15)2023 Aug 02.
Artículo en Inglés | MEDLINE | ID: mdl-37568490

RESUMEN

The aim of this prospective study is to investigate implant stability and the reliability of different measuring devices according to implant placement site and duration in patients aged over 65 years. The study evaluated 60 implants (diameter: 3.5/4.0/4.5/5.0 mm and length: 8.5/10.0/11.5 mm) in 60 patients aged ≥ 65 years. The implant placement sites were divided into six evenly distributed sections (n = 10), i.e., maxillary right-posterior, A; maxillary anterior, B; maxillary left-posterior, C; mandibular right-posterior, D; mandibular anterior, E; mandibular left-posterior, F. Participants visited the hospital six times: implant surgery, 1V; stitch removal, 2V; 1-month follow-up, 3V; 2-month follow-up, 4V; before final restoration delivery, 5V; and after final restoration delivery, 6V. The implant stability was evaluated with the Osstell Mentor (ISQ), Periotest M (PTV), and Anycheck (IST). The mean values of ISQ, PTV, and IST were analyzed (α = 0.05). ISQ, PTV, and IST results of 4V and 5V were significantly higher than those of 1V (p < 0.05). The lowest ISQ results occurred in the E location at 4V and 5V (p < 0.05). In all mandibular locations, IST results of 6V were significantly higher than those of 1V, 2V, 3V, and 4V (p < 0.05). ISQ results were negatively correlated with PTV and positively correlated with IST, and PTV was negatively correlated with IST. By considering various factors affecting the stability of the implant, it is necessary to determine the appropriate implant load application time. This could help increase the implant success rate in elderly patients. And as a diagnostic device for implant stability and the evaluation of osseointegration in elderly patients, Anycheck was also able to prove its relative reliability compared to Osstell ISQ Mentor and Periotest M.

10.
Ann Dermatol ; 35(3): 173-182, 2023 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-37290951

RESUMEN

BACKGROUND: Currently, there is no consensus on the treatment of psoriasis in Korean patients. OBJECTIVE: This study aimed to establish a consensus on the basic therapeutic principles for Korean patients with plaque psoriasis. METHODS: Using the modified Delphi method, a steering committee proposed 53 statements for the first Delphi round, which covered five subjects: (1) the goal of treatment and evaluation of disease severity, (2) topical therapy, (3) phototherapy, (4) conventional systemic therapy, and (5) biologic therapy. The panel of dermatologists scored the level of agreement for each statement on a ten-point scale with scores ranging from 1 (strongly disagree) to 10 (strongly agree). After discussing the results of the first round, the committee reformulated 41 statements. Finally, consensus was defined as more than 70% of the second round scores being ≥7. RESULTS: The panel participants strongly agreed that the ideal treatment goals for Korean patients with plaque psoriasis should include complete skin clearance and high dermatological quality of life. A strong consensus was also reached on the use of topical agents for psoriasis of any severity, the consideration of phototherapy before biologics therapy, the conventional systemic agents for moderate-to-severe psoriasis, and the recommendation of biologic for retractable psoriasis to conventional systemic therapy and phototherapy. CONCLUSION: This modified Delphi panel established an expert consensus on the therapeutic approach for Korean patients with plaque psoriasis. This consensus may improve the treatment outcomes for psoriasis in Korea.

11.
Ann Dermatol ; 35(3): 217-228, 2023 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-37290955

RESUMEN

BACKGROUND: Recent studies suggest that MEK1/2 inhibitors, including binimetinib, significantly improve malignant melanoma (MM) patient survival. Growing evidence suggests that phytochemicals, especially curcumin, can overcome drug resistance in cancer cells through a variety of mechanisms. OBJECTIVE: This study aims to examine curcumin's efficacy in vitro combined with binimetinib in human MM cells. METHODS: We used 2D monolayer and 3D spheroid human epidermal melanocyte culture models, HEMn-MP (human epidermal melanocytes, neonatal, moderately pigmented), and two human MM cell lines, G361 and SK-MEL-2, to evaluate cell viability, proliferation, migration, death, and reactive oxygen species (ROS) production following single therapy treatment, with either curcumin or binimetinib, or a combination of both. RESULTS: Compared to MM cells treated with single therapy, those with combination therapy showed significantly decreased cell viability and increased ROS production. We observed apoptosis following both single and combination therapies. However only those who had had combination therapy had necroptosis. CONCLUSION: Collectively, our data demonstrates that curcumin exerts significant synergistic anticancer effects on MM cells by inducing ROS and necroptosis when combined with binimetinib. Therefore, a strategy of adding curcumin to conventional anticancer agents holds promise for treating MM.

12.
Clin Oral Implants Res ; 34(6): 575-581, 2023 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-36920314

RESUMEN

OBJECTIVES: This study aimed to evaluate the effect of aging on the changes in implant stability over time following implant placement. MATERIALS AND METHODS: A total of 104 patients in four age ranges (group 1: <60 years, group 2: 61-70 years, group 3: 71-80 years, and group 4: >80 years) were included. Bone-level tapered implants were placed without implementing any bone augmentation procedure. The final torque value displayed on the implant engine during implant insertion was recorded. Cone-beam computed tomography (CBCT) was performed immediately after surgery to analyze the bone quality around the implant. Implant stability was measured immediately after surgery and 2, 4, and 8 weeks after surgery. RESULTS: In the CBCT image, higher grayscale values were observed in the order of group 1, group 2, and groups 3/4, with statistical significance (p < .05). There was no significant difference in the insertion torque values between age groups (p ≥ .05). Groups 1 and 2 showed lower implant stability values after 2 and 4 weeks compared to immediately and 8 weeks after surgery (p < .05); however, groups 3 and 4 showed no significant difference between the results measured at different timepoints (p ≥ .05). CONCLUSIONS: Implant treatment in elderly patients is successful showing a settled implant stability over time following implant placement when the implant is appropriately engaged in the alveolar bone in the absence of bone augmentation.


Asunto(s)
Implantes Dentales , Humanos , Anciano , Lactante , Estudios Prospectivos , Implantación Dental Endoósea/métodos , Huesos , Densidad Ósea , Torque , Tomografía Computarizada de Haz Cónico/métodos
13.
J Dent ; 130: 104450, 2023 03.
Artículo en Inglés | MEDLINE | ID: mdl-36773741

RESUMEN

OBJECTIVES: To investigate the influence of thermal cycling and mechanical loading (TCML) aging on fracture resistance and wear behavior of various chairside computer-aided-designed/computer-assisted-manufactured (CAD/CAM) premolar crowns cemented on standardized tooth abutments. METHODS: Eighty chairside CAD/CAM crowns were prepared using lithium disilicate (IPS e.max CAD; EM), zirconia-infiltrated lithium silicate (Celtra Duo; CD), polymer-infiltrated ceramic network (Vita Enamic; VE), and resin nanoceramics (Cerasmart; CS) (n = 20). The specimens were divided into two groups (n = 10). In one group, they were subjected to TCML: thermocycling (6000 cycles in distilled water at 5-55 °C) and mechanical loading (50 N for 1.2 × 106 cycles), while in control group they were stored in distilled water (37 °C for 24 h). The fracture load, height loss, and volume wear of the crowns were measured after TCML. Fractography was performed on fractured specimens. Data were analyzed using analysis of variance and multiple comparison tests (α=0.05). RESULTS: The mean fracture loads of EM and CD were significantly higher than those of EC and CS (p<0.05). There was no significant change in the fracture load of any CAD/CAM crowns after TCML (p>0.05). CS exhibited a significantly higher volume wear than the other materials investigated. The wear tracts of all TCML crowns acted as failure origins during the fracture test. CONCLUSIONS: The fracture resistance of glass-ceramic CAD/CAM crowns was significantly higher than that of resin composite crowns. A 5-year TCML aging did not affect the fracture resistance of CAD/CAM crowns investigated. However, TCML treatment produces a larger wear track in CS than in other materials. CLINICAL SIGNIFICANCE: Appropriate chairside CAD/CAM restorative material should be selected for successful clinical practice after considering the fracture and wear resistance of the crowns.


Asunto(s)
Cerámica , Fracaso de la Restauración Dental , Porcelana Dental , Coronas , Materiales Dentales , Resinas Compuestas , Diseño Asistido por Computadora , Agua , Ensayo de Materiales , Análisis del Estrés Dental
14.
J Dent Educ ; 87(2): 198-207, 2023 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-36176031

RESUMEN

PURPOSE/OBJECTIVES: This study aimed to evaluate a nonface-to-face crown designing module in a preclinical dental course. METHODS: Free dental planning software (Blue Sky Plan) was installed on the personal computers of dental college students, and a #46 full veneer crown designing practice was performed individually. An online survey was conducted on the computers' specification and main usage of the students, the practice process, and results. Statistical analysis was conducted to analyze the association between variables, such as "operating system," "central processing unit ," "number of cores," "random-access memory (RAM)," "graphic card," and task performance. RESULTS: Of the D2 students, 75.4% (52 of 69) responded to the survey. Overall, 96% of the respondents used their computers, and all respondents had no problem running the program. Most of the students marked their level of computer literacy as intermediate and had purchased the computers for the purpose of performing light work. The most common specifications of the computer were Intel i5, quad core, 8 GB RAM, and Windows 10. Students had little experience with computer-aided design/computer-aided manufacturing before the class. The relationship between computer specifications and task performance was not statistically significant. CONCLUSIONS: Overall, students with intermediate-level computer literacy used computers with less than the recommended specifications of the program; however, they were able to run the program and individually proceed with modules to submit results. Using an individually available crown designing program can provide an opportunity to diversify curricula and broaden students' perspectives even under circumstances like the COVID-19 pandemic that limits intimate face-to face classes.


Asunto(s)
COVID-19 , Pandemias , Humanos , Prostodoncia/educación , Estudiantes de Odontología , Diseño Asistido por Computadora
15.
Ann Dermatol ; 34(6): 451-460, 2022 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-36478427

RESUMEN

BACKGROUND: Rosacea is a chronic inflammatory disease which requires treatment to maintain remission. OBJECTIVE: Recently, the effect of Demodex mites in recurrence of rosacea has been described. Although there is limited data, previous reports have suggested that oral metronidazole demonstrated efficacy in treatment of rosacea. METHODS: Fifty-eight Korean patients with rosacea who received treatment with oral minocycline (50 mg twice daily) only or with two-week of oral metronidazole (250 mg thrice daily) were evaluated retrospectively. Their responses were evaluated by Investigator's Global Assessment (IGA), Clinician's Erythema Assessment (CEA), and patient's Global Assessment. The recurrence rate and odds ratio of risk factors for recurrence were also estimated. RESULTS: The combination treatment group reported earlier clinical improvement and lower mean IGA and CEA than the monotherapy group. Approximately 48% of patients with combination treatment did not show relapse within 24 weeks, which is significantly higher than that in the monotherapy group (p=0.042). CONCLUSION: Add-on therapy of oral metronidazole appeared to be a significant protective factor for recurrence of rosacea (p<0.05). This study suggests that oral metronidazole can be added to oral minocycline to reduce relapses in rosacea patients with tolerable safety.

16.
J Prosthet Dent ; 128(1): 79-88, 2022 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-33546857

RESUMEN

STATEMENT OF PROBLEM: The properties of dental computer-aided design and computer-aided manufacturing (CAD-CAM) materials vary. Studies regarding the effects of aging on the properties of these materials are lacking. PURPOSE: The purpose of this in vitro study was to evaluate the changes in the mechanical and surface properties of different CAD-CAM materials after thermocycling and mechanical loading. MATERIAL AND METHODS: In total, 150 bar-shaped specimens (17.0×4.0×2.0 mm) were prepared from feldspathic glass-ceramic (VM; Vitablocs Mark II), lithium disilicate glass-ceramic (EX; IPS e.max CAD), zirconia-reinforced lithium silicate glass-ceramic (CD; Celtra Duo), polymer-infiltrated ceramic network (VE; Vita Enamic), and resin-nanoceramic (CS; Cerasmart). Each type was divided into 2 groups (n=15; each). One group was subjected to thermocycling in distilled water at 5 °C to 55 °C for 6000 cycles and 50 N mechanical loading for 1.2×106 cycles. The other group was stored in 37 °C water for 24 hours. Nanoindentation hardness, Young modulus, and 3-point flexural strength were measured for the analyses of the mechanical properties. Surface roughness, surface microstructure, and elemental composition were measured to analyze the surface characteristics. Statistical analyses were performed with 1-way ANOVA with the Tukey HSD post hoc test, independent samples t test, Kruskal-Wallis test with Bonferroni post hoc test, Mann-Whitney U test, and 2-way ANOVA (α=.05). RESULTS: Before and after aging, CS exhibited the lowest hardness (1.20 to 1.04 GPa) and Young modulus (13.76 to 13.48 GPa) values (P<.05). EX exhibited the highest flexural strengths (393.43 to 391.86 MPa), and VM exhibited the lowest (109.98 to 112.73 MPa) values (P<.05). CS exhibited the highest surface roughness (Sa and Sq; 10.60 to 28.82, 14.21 to 38.27 nm) values (P<.05). After aging, the hardness and Young modulus of VM, EX, and VE decreased significantly (P<.001). No significant difference was observed in the flexural strengths of the CAD-CAM materials (P>.05). Significant increases were observed in the surface roughness of all the materials (P<.05), with altered microstructures. Except for the flexural strength, the mechanical properties and surface characteristics of the CAD-CAM materials were significantly affected by the material type after aging. CONCLUSIONS: Before and after aging, resin-nanoceramic exhibited the lowest hardness and Young modulus, and the highest surface roughness. Lithium disilicate glass-ceramic exhibited the highest flexural strength and feldspathic glass-ceramic exhibited the lowest value. After aging, increased surface roughness and microstructure alterations were observed. Significant interactions between aging process and material type were found for the mechanical properties and surface characteristics except for the flexural strength.


Asunto(s)
Cerámica , Porcelana Dental , Cerámica/química , Diseño Asistido por Computadora , Materiales Dentales/química , Resistencia Flexional , Dureza , Ensayo de Materiales , Propiedades de Superficie , Agua
18.
Materials (Basel) ; 14(11)2021 Jun 06.
Artículo en Inglés | MEDLINE | ID: mdl-34204092

RESUMEN

The aim of this in vitro study was to investigate the fracture resistance, fracture failure pattern, and fractography of four types of chairside computer-aided design/computer-aided manufacturing (CAD/CAM) restoration materials in teeth and titanium abutments fabricated using a standardization method. An artificial mandibular left first premolar prepared for all-ceramic crown restoration was scanned. Forty extracted mandibular molars and cylindrical titanium specimens were milled into a standardized shape. A total of eighty CAD/CAM restoration blocks were milled into a crown and twenty pieces of each lithium disilicate (LS), polymer-infiltrated-ceramic-network (PICN), resin nano ceramic (RNC), and zirconia-reinforced lithium silicate (ZLS) materials were used. Crowns were bonded to abutments, and all specimens underwent thermal cycling treatment for 10,000 cycles. Fracture resistance was measured using a universal testing machine and fracture failure patterns were analyzed using optical microscopy and scanning electron microscopy. Statistical differences were analyzed using appropriate ANOVA, Tukey HSD post hoc tests, and independent sample t-tests (α = 0.05). The results indicated that, in both teeth abutments and titanium abutments, the fracture resistances showed significantly the highest values in LS and the second highest in ZLS (p < 0.05). The fracture resistances based on teeth abutments and titanium abutments were significantly different in all the CAD/CAM restoration materials (p < 0.05). There are statistically significant correlations between the types of materials and the types of abutments (p < 0.05). Each of the different materials showed different fracture failure patterns, and there was no noticeable difference in fractographic analysis. Lithium disilicates and zirconia-reinforced lithium silicates exhibited statistically high fracture resistance, indicating their suitability as restoration materials for natural teeth or implant abutments. There were no distinct differences in the fracture pattern based on the restoration and abutment materials showed that the fracture initiated at the groove where the ball indenter was toughed and propagated toward the axial wall.

19.
J Prosthet Dent ; 126(5): 679-685, 2021 Nov.
Artículo en Inglés | MEDLINE | ID: mdl-33041076

RESUMEN

STATEMENT OF PROBLEM: The optical properties of esthetic computer-aided design and computer-aided manufacturing (CAD-CAM) materials can change depending on the clinical situation. Studies that compare esthetic CAD-CAM materials based on their optical properties are lacking. PURPOSE: The purpose of this in vitro study was to evaluate the optical properties of esthetic CAD-CAM specimens after ultraviolet (UV) aging based on the type and thickness of the material. MATERIAL AND METHODS: In total, 240 plate-shaped specimens (14×12×1 mm and 14×12×2 mm) of a nanohybrid composite resin (Tetric CAD), a fine-structure feldspathic ceramic (Vitablocs Mark II), 2 different glass-ceramics (IPS Empress CAD and IPS e.max CAD), a zirconia-reinforced lithium silicate glass-ceramic (Celtra Duo), a polymer-infiltrated ceramic network (Vita Enamic), and 2 different resin nanoceramics (Cerasmart and Lava Ultimate) were fabricated (n=15). The optical parameters were analyzed by spectrophotometry before and after UV aging. The brightness (L∗), red green (a∗), yellow-blue (b∗), chroma (Ch), and hue (h) were measured, and the color difference (ΔE00) values were calculated. The translucency parameter (TP), total transmittance (Tt), and contrast ratio (CR) were also determined. Statistical analyses were performed with 1-way ANOVA, the Tukey honestly significant difference post hoc test, independent- and paired-samples t tests, and 2-way ANOVA (α=.05). RESULTS: Significant interactions were observed for the aging process, material type, and thickness for all optical parameters (P<.05). L∗, TP, and Tt had lower values, while CR had higher values for the aging group than that of the control group (P<.05). The h, TP, and Tt values were higher, whereas the b∗ and CR values were lower for the 1-mm group than those of the 2-mm group (P<.05). The highest ΔE00 value was found in the Lava Ultimate 1-mm group (ΔE00=3.21) and 2-mm group (ΔE00=2.42). The lowest ΔE00 value was found in the Vitablocs Mark II 1-mm group (ΔE00=0.31). The highest TP and Tt and the lowest CR values were observed for Tetric CAD; the lowest TP and Tt, and the highest CR values were noted in Celtra Duo (P<.05). CONCLUSIONS: The optical properties of the CAD-CAM specimens were affected by the aging process, material type, and thickness, and the color stability was clinically applicable in all CAD-CAM materials except groups Lava Ultimate and Cerasmart(ΔE00<2.25). Resin nanoceramics exhibited the greatest color changes after UV aging, and a 2-mm thickness is recommended to ensure acceptable color stability. The zirconia-reinforced lithium silicate glass-ceramic was the most opaque, with a 1-mm thickness providing increased translucency.


Asunto(s)
Porcelana Dental , Estética Dental , Cerámica , Color , Diseño Asistido por Computadora , Materiales Dentales , Ensayo de Materiales , Propiedades de Superficie
20.
Dermatol Ther ; 33(6): e14520, 2020 11.
Artículo en Inglés | MEDLINE | ID: mdl-33174351

RESUMEN

Flushing and erythema are the most common symptoms of rosacea; however, management of these symptoms remains challenging. Recent case studies suggest that treatment with carvedilol may reduce facial flushing and persistent erythema in the pathogenesis of rosacea. To find the effect of carvedilol in the treatment of facial flushing and erythema in rosacea. Twenty-four rosacea patients treated with carvedilol for facial flushing and erythema were retrospectively reviewed. All patients were prescribed carvedilol 6.25 mg either once or twice per day, and the daily dose was gradually titrated up to 12.5 mg. Clinical erythema severity was assessed by the Clinician's Erythema Assessment (CEA) and Patient's Self-Assessment (PSA) scales. Improvement of CEA and PSA scores compared to the baseline were assessed. The proportion of patients with improvement of two or more points from baseline in CEA score was analyzed by sex, previous treatment exposure, disease duration, and subtypes. The mean change of -1.6 in the CEA score and of -1.8 in the PSA score showed significant improvement from baseline. Erythematotelangiectatic rosacea (ETR) patients achieved more than 2-points improvement in the CEA score, compared with non-ETR patients (53.8% vs 16.7% [P = .035]). No statistically significant differences were observed by sex, disease duration, or previous treatment exposure. No serious adverse event was observed. Carvedilol can be an effective and safe treatment option for rosacea patients suffering from facial flushing and erythema.


Asunto(s)
Carvedilol/uso terapéutico , Eritema , Rosácea , Eritema/diagnóstico , Eritema/tratamiento farmacológico , Eritema/etiología , Rubor/diagnóstico , Rubor/tratamiento farmacológico , Rubor/etiología , Humanos , Estudios Retrospectivos , Rosácea/diagnóstico , Rosácea/tratamiento farmacológico , Resultado del Tratamiento
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