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1.
Clin Linguist Phon ; : 1-27, 2024 Sep 17.
Artigo em Inglês | MEDLINE | ID: mdl-39287150

RESUMO

Children with developmental language disorder (DLD) experience difficulties with a range of morphosyntactic skills, particularly with tense and subject - verb agreement. Many studies have examined verb-morphology production in children with DLD. We extend this line of research by profiling verb-morphology comprehension in 67 monolingual Saudi Arabic-speaking children, comprising 33 with DLD (M = 61 months, SD = 10.70), and 34 age-matched typically developing (TD) children (M = 63 months, SD = 8.94). Children completed a novel picture selection task developed to assess their comprehension of verb tense, gender agreement, and number agreement. Children with DLD scored significantly lower than TD children on the verb morphology comprehension task. They showed greater difficulty identifying verb tense forms, particularly future tense. They also demonstrated lower accuracy in identifying subject-verb agreement in general, with specific difficulty in comprehending masculine verbs, and singular verbs. These findings were compared with production verb-morphology data from previous Arabic studies. Overall, this study highlights the challenges experienced by Arabic-speaking children with DLD in comprehending verb morphology, particularly tense and subject-verb agreement inflections. These findings can be used to tailor appropriate assessment designs and interventions for an Arabic-speaking DLD population.

2.
Cureus ; 16(8): e67311, 2024 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-39301332

RESUMO

Corneal dystrophies are a group of rare genetic eye disorders characterized by the accumulation of abnormal material in different layers of the cornea, potentially leading to vision impairment. In vivo confocal microscopy (IVCM) is an emerging non-invasive imaging and diagnostic tool that helps study the ocular surface microstructure. This case report examines the clinical characteristics of Avellino corneal dystrophy in a young patient through the use of slit lamp examination, IVCM, and optical coherence tomography (OCT) in order to assess the effectiveness of these non-invasive tests as diagnostic tools.

3.
J Clin Ultrasound ; 52(5): 558-565, 2024 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-38538067

RESUMO

OBJECTIVE: Our aim was to investigate the significance of cerebro-placento-uterine ratio CPUR, a new Doppler index, and fetal cardiac parameters (Mod MPI, EFT) in early-onset preeclampsia (EOPE) and to examine whether these parameters are related to perinatal outcome. STUDY DESIGN: Forty participants diagnosed with EOPE (preeclampsia cases diagnosed before 34 weeks of gestation) and 40 healthy pregnant women were included in this study. Demographic data were recorded. Doppler parameters such as middle cerebral artery (MCA), umbilical artery (UA), and uterine artery (Ut-A), and left modified myocardial performance index (Mod-MPI) and epicardial fat thickness (EFT) were measured. Cerebroplacental ratio (CPR) was determined by dividing MCA pulsatility index (PI) by UA PI. CPUR was calculated as the ratio of CPR to mean UtA-PI (CPUR = CPR/UtA-PI). All parameters were compared between the EOPE and control groups. Correlation tests were used to examine the relationship between Doppler parameters and perinatal outcome. p values less than 0.05 were considered statistically significant. RESULTS: The pulsatility index of the middle cerebellar artery, CPUR and CPR values were statistically lower in the EOPE group than in the control group (p = 0.002; p = <0.001; p = <0.001; respectively). No statistical differences were found between groups for isovolumetric contraction time (ICT), isovolumetric relaxation time (IRT), ejection time (ET), left mod-MPI, EFT (p = 0.117; p = 0.093; p = 0.398; p = 0.882; p = 0.202, respectively). Umbilical artery Doppler pulsatility index (PI), mean uterine artery Doppler pulsatility index (PI), were higher in the EOPE group than in the control group (p = 0.006; and p = <0.001, respectively). The CPUR value for predicting EOPE was ≤1.3652 with 74. 4% sensitivity and 94.9% specificity. Positive correlations were found between CPUR, CPR, and some neonatal parameters. CONCLUSION: CPUR, a new index combining fetal and uterine Doppler indices, may add contribution to predict adverse perinatal outcome and EOPE.


Assuntos
Artéria Cerebral Média , Placenta , Pré-Eclâmpsia , Ultrassonografia Doppler , Ultrassonografia Pré-Natal , Artérias Umbilicais , Artéria Uterina , Humanos , Feminino , Gravidez , Ultrassonografia Pré-Natal/métodos , Adulto , Pré-Eclâmpsia/fisiopatologia , Pré-Eclâmpsia/diagnóstico por imagem , Artéria Uterina/diagnóstico por imagem , Artéria Uterina/fisiopatologia , Ultrassonografia Doppler/métodos , Artérias Umbilicais/diagnóstico por imagem , Artérias Umbilicais/fisiopatologia , Artéria Cerebral Média/diagnóstico por imagem , Artéria Cerebral Média/fisiopatologia , Placenta/diagnóstico por imagem , Placenta/irrigação sanguínea , Coração Fetal/diagnóstico por imagem , Coração Fetal/fisiopatologia , Útero/irrigação sanguínea , Útero/diagnóstico por imagem , Fluxo Pulsátil/fisiologia
4.
Oncol Lett ; 27(4): 145, 2024 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-38385117

RESUMO

Breast cancer is most frequently diagnosed among women aged 65-74 years and the prevalence of comorbidities in elderly patients with breast cancer is 32.2%. In addition, polypharmacy is quite common in these patients. Understanding the interaction between breast cancer treatment modalities and comorbidities is important, particularly in elderly patients, as comorbidities affect the choice of appropriate treatment and are independent risk factors for survival. A total of three oral cyclin-dependent kinase 4 and 6 inhibitors (CDK4/6i), palbociclib, ribociclib and abemaciclib, notably prolonged progression-free survival when combined with endocrine therapy (ET), compared with ET alone in patients with advanced breast cancer (ABC). The present review article therefore addressed the safety, tolerability and toxicity of CDK4/6i treatment in ABC management, compiled real-world data on how multiple clinical and pharmacological features may affect the choice of these drugs and provided practical recommendations for clinical approaches. Before starting treatment with CDK4/6i drugs, all ongoing medical conditions should be inventorized and re-graded, and examination should be performed for any additional disease that the patient may not be aware of. It is also important to obtain a detailed history of concomitant drugs, including prescription and over-the-counter drugs, vitamins, supplements and herbal products. In addition, patients should be advised to consult their oncologist before starting any new medication.

5.
Proc Natl Acad Sci U S A ; 115(45): 11369-11376, 2018 11 06.
Artigo em Inglês | MEDLINE | ID: mdl-30397135

RESUMO

Is there a universal hierarchy of the senses, such that some senses (e.g., vision) are more accessible to consciousness and linguistic description than others (e.g., smell)? The long-standing presumption in Western thought has been that vision and audition are more objective than the other senses, serving as the basis of knowledge and understanding, whereas touch, taste, and smell are crude and of little value. This predicts that humans ought to be better at communicating about sight and hearing than the other senses, and decades of work based on English and related languages certainly suggests this is true. However, how well does this reflect the diversity of languages and communities worldwide? To test whether there is a universal hierarchy of the senses, stimuli from the five basic senses were used to elicit descriptions in 20 diverse languages, including 3 unrelated sign languages. We found that languages differ fundamentally in which sensory domains they linguistically code systematically, and how they do so. The tendency for better coding in some domains can be explained in part by cultural preoccupations. Although languages seem free to elaborate specific sensory domains, some general tendencies emerge: for example, with some exceptions, smell is poorly coded. The surprise is that, despite the gradual phylogenetic accumulation of the senses, and the imbalances in the neural tissue dedicated to them, no single hierarchy of the senses imposes itself upon language.


Assuntos
Percepção Auditiva/fisiologia , Idioma , Percepção Olfatória/fisiologia , Psicolinguística , Percepção Gustatória/fisiologia , Percepção do Tato/fisiologia , Percepção Visual/fisiologia , África , Ásia , Comparação Transcultural , Diversidade Cultural , Humanos , América Latina , Fonética , Semântica , Língua de Sinais
6.
Clin Respir J ; 11(6): 975-982, 2017 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-26780291

RESUMO

OBJECTIVES: Chronic obstructive pulmonary disease (COPD) remains a globally significant cause of mortality, although COPD mortality varies from country to country, and across different regions within each country. The primary objective of this study was to determine the mortality rates of COPD patients who present with acute respiratory failure (ARF) to a tertiary care referral center in different stages of their follow-up (ICU, in-hospital and after discharge). The secondary objective was to determine factors associated with mortality in this group of patients. RESULTS: Medical records of consecutive COPD patients over a 10-year period were reviewed.The study included 147 patients. Of these, 72 were treated initially with noninvasive positive pressure ventilation (NIPPV), and 12 of these required intubation after NIPPV failed. Therefore, 86 patients were intubated for invasive mechanical ventilation (IMV), while NIPPV was succesful in 60 patients. Survival time was independently associated with advanced age, high APACHE II score, co-morbidity and the need for IMV. The cumulative mortality was 27% in the medical ICU and 31% in hospital following ICU discharge. The mortality rate at 1, 2 and 5 years was 54%, 66% and 84%, respectively. CONCLUSION: COPD patients admitted to the ICU for ARF have an approximately 70% chance of leaving hospital alive, but half of these may die in the first 6 months after discharge. The risk factors related to mortality were advanced age, high APACHE II score, co-morbidity and IMV requirement.


Assuntos
Unidades de Terapia Intensiva/normas , Ventilação não Invasiva/efeitos adversos , Doença Pulmonar Obstrutiva Crônica/mortalidade , Respiração Artificial/efeitos adversos , Síndrome do Desconforto Respiratório/complicações , APACHE , Idoso , Idoso de 80 Anos ou mais , Comorbidade , Progressão da Doença , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Mortalidade/tendências , Ventilação não Invasiva/métodos , Alta do Paciente/normas , Estudos Prospectivos , Doença Pulmonar Obstrutiva Crônica/epidemiologia , Doença Pulmonar Obstrutiva Crônica/fisiopatologia , Respiração Artificial/métodos , Síndrome do Desconforto Respiratório/terapia , Fatores de Risco , Centros de Atenção Terciária/estatística & dados numéricos , Resultado do Tratamento , Turquia/epidemiologia
7.
Tuberk Toraks ; 64(2): 137-43, 2016 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-27481080

RESUMO

INTRODUCTION: Conventional transbronchial needle aspiration biopsy (C-TBNA) is a technique in evaluating mediastinal/hilar lymph nodes (LN). We aimed to investigate diagnostic yield (DY) and safety of C-TBNAs performed in a single university clinic. PATIENTS AND METHODS: We retrospectively reviewed 363 consecutive C-TBNA procedures in 219 patients. The DY and its relationship with location, shortest diameter, SUVmax of LN, and number of sampled stations were evaluated. RESULT: Procedures were diagnostic in 257 (71%) LNs. The most common diagnoses were malignancy (n= 109.30%) and granulomatous inflammation (n= 68, 18.7%).The ratio of patients with at least one diagnostic cytology result was 77% (n= 168). DY was significantly increased with the increased number of sampled LNs (p= 0.033) and larger LN diameter (p< 0.001). Sensitivity, specificity, positive, and negative predictive values were 83.3%, 43.2%, 79.6%, and 49.3% respectively for cut-off LN diameter of 11.5 mm. There was nearly a significant relationship between DY and SUVmax (p= 0.05, cut-off= 4.8). The highest DY was in subcarinal LN (77.4%). No major complications were recorded. CONCLUSIONS: The DY of C-TBNA was 71%. The ratio of the patients with at least one diagnostic cytology result was 77%. The most common diagnoses were malignancy and granulomatous inflammation. The DY of C-TBNA was increased with the increased number of sampled LNs, larger LN diameter, and increased SUVmax. C-TBNA is a safe procedure.


Assuntos
Biópsia por Agulha Fina/métodos , Broncoscopia/métodos , Neoplasias Pulmonares/patologia , Linfonodos/patologia , Adulto , Feminino , Humanos , Pulmão/patologia , Masculino , Doenças do Mediastino/patologia , Pessoa de Meia-Idade , Estudos Retrospectivos , Sensibilidade e Especificidade
10.
Dev Sci ; 17(4): 636-43, 2014 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-24636133

RESUMO

Pitch is often described metaphorically: for example, Farsi and Turkish speakers use a 'thickness' metaphor (low sounds are 'thick' and high sounds are 'thin'), while German and English speakers use a height metaphor ('low', 'high'). This study examines how child and adult speakers of Farsi, Turkish, and German map pitch and thickness using a cross-modal association task. All groups, except for German children, performed significantly better than chance. German-speaking adults' success suggests the pitch-to-thickness association can be learned by experience. But the fact that German children were at chance indicates that this learning takes time. Intriguingly, Farsi and Turkish children's performance suggests that learning cross-modal associations can be boosted through experience with consistent metaphorical mappings in the input language.


Assuntos
Desenvolvimento da Linguagem , Percepção da Altura Sonora , Adulto , Criança , Desenvolvimento Infantil , Pré-Escolar , Formação de Conceito , Alemanha , Humanos , Irã (Geográfico) , Idioma , Aprendizagem , Linguística , Metáfora , Países Baixos , Psicolinguística , Som , Turquia , Comportamento Verbal
11.
Dev Sci ; 16(1): 111-5, 2013 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-23278932

RESUMO

The origin of color categories is under debate. Some researchers argue that color categories are linguistically constructed, while others claim they have a pre-linguistic, and possibly even innate, basis. Although there is some evidence that 4-6-month-old infants respond categorically to color, these empirical results have been challenged in recent years. First, it has been claimed that previous demonstrations of color categories in infants may reflect color preferences instead. Second, and more seriously, other labs have reported failing to replicate the basic findings at all. In the current study we used eye-tracking to test 8-month-old infants' categorical perception of a previously attested color boundary (green-blue) and an additional color boundary (blue-purple). Our results show that infants are faster and more accurate at fixating targets when they come from a different color category than when from the same category (even though the chromatic separation sizes were equated). This is the case for both blue-green and blue-purple. Our findings provide independent evidence for the existence of color categories in pre-linguistic infants, and suggest that categorical perception of color can occur without color language.


Assuntos
Desenvolvimento Infantil/fisiologia , Cor , Discriminação Psicológica/fisiologia , Desenvolvimento da Linguagem , Potenciais Evocados Auditivos do Tronco Encefálico/fisiologia , Movimentos Oculares/fisiologia , Feminino , Humanos , Lactente , Masculino , Estimulação Luminosa
12.
J Exp Child Psychol ; 114(2): 173-86, 2013 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-22960203

RESUMO

Perceptual experiences in one modality are often dependent on activity from other sensory modalities. These cross-modal correspondences are also evident in language. Adults and toddlers spontaneously and consistently map particular words (e.g., 'kiki') to particular shapes (e.g., angular shapes). However, the origins of these systematic mappings are unknown. Because adults and toddlers have had significant experience with the language mappings that exist in their environment, it is unclear whether the pairings are the result of language exposure or the product of an initial proclivity. We examined whether 4-month-old infants make the same sound-shape mappings as adults and toddlers. Four month-olds consistently distinguished between congruent and incongruent sound-shape mappings in a looking time task (Experiment 1). Furthermore, mapping was based on the combination of consonants and vowels in the words given that neither consonants (Experiment 2) nor vowels (Experiment 3) alone sufficed for mapping. Finally, we confirmed that adults also made systematic sound-shape mappings (Experiment 4); however, for adults, vowels or consonants alone sufficed. These results suggest that some sound-shape mappings precede language learning, and may in fact aid in language learning by establishing a basis for matching labels to referents and narrowing the hypothesis space for young infants.


Assuntos
Aprendizagem por Associação , Desenvolvimento da Linguagem , Reconhecimento Visual de Modelos , Fonética , Psicologia da Criança , Percepção da Fala , Simbolismo , Atenção , Aprendizagem por Discriminação , Feminino , Humanos , Lactente , Masculino
13.
J Pediatr Surg ; 47(10): 1913-8, 2012 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-23084206

RESUMO

BACKGROUND/PURPOSE: The purpose of our study was to define the factors related to recurrence of labial fusion. METHODS: The data of 110 patients diagnosed with labial fusion were gathered. The data collected and queried included age and body weight of the patient, season of presentation/occurrence, frequency of diaper change, frequency of diaper dermatitis, products used for hygiene, duration of breast milk feeding, infections, presence of allergy, thickness of the adhesion, mother's use of oral contraceptive drugs before pregnancy, mother's use of alcohol/drugs/cigarettes or presence of disease during pregnancy, the number of recurrences, treatment method, presence of labial fusion among maternal sisters or any relatives, and blood estrogen levels. RESULTS: Eighty-one patients (73.6%) with labial fusion were admitted for the first time, whereas 29 patients (26.4%) had been treated previously at least once. The adhesion was denser in patients with recurrence. There was no correlation between recurrence of labial fusion and age-based body weight percentile, frequency of diaper change, frequency of diaper dermatitis, hygiene products used, presence of infection, presence of allergy, mother's use of oral contraceptive drugs before pregnancy, or presence of any pathology in other family members. CONCLUSIONS: The products used for hygiene, frequency of diaper dermatitis, duration of breast milk feeding, presence of infection, and prenatal factors showed no correlation with the recurrence of labial fusion.


Assuntos
Higiene , Doenças da Vulva/etiologia , Feminino , Humanos , Lactente , Recidiva , Fatores de Risco
14.
J Prosthet Dent ; 102(4): 235-41, 2009 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-19782826

RESUMO

STATEMENT OF PROBLEM: Despite recent advances in adhesive dentistry, resin cement/dentin adhesive combinations are not able to prevent microleakage in ceramic inlays. Marginal quality of tooth-colored restorations in large Class II cavities is satisfactory in enamel margins, but microleakage in dentin margins remains a concern. PURPOSE: The purpose of this study was to evaluate the microleakage of all-ceramic inlays luted with 2 dual-polymerizing resin cements or 1 autopolymerizing resin cement in combination with different dentin adhesives. MATERIAL AND METHODS: One hundred and twenty extracted human mandibular third molars were used in this study. Teeth were prepared to receive Class II MOD inlays with enamel gingival margins on 1 proximal surface and dentin gingival margins on the other surface. One hundred and twenty prepared teeth were divided into 3 groups of 40; 1 group for each resin cement: RelyX ARC, Variolink II, or Panavia 21. Each of the 3 groups were further divided into 4 dentin adhesive groups; Single Bond, ExciTE DSC, ED Primer, or Admira Bond. Each of the resin cements were used in combination with the 4 dentin adhesives, and IPS Empress ceramic inlays were placed with 12 different cement/adhesive combinations. After 1000 thermal cycles in a 5 degrees -55 degrees C water bath with a dwell time of 30 seconds, all specimens were subjected to cyclic axial mechanical loading. Then the restored teeth were stored in 0.5% basic fuchsin solution for 24 hours. The extent of dye penetration along the margins was measured with a stereomicroscope at x40 magnification. The data were evaluated statistically using repeated-measures ANOVA and Duncan tests (alpha=.05). RESULTS: Microleakage at dentin margins was greater than that at enamel margins (P<.05) for all groups. Variolink II and RelyX ARC resin cements showed significantly lower microleakage results than Panavia 21 with all dentin adhesives in enamel margins. For dentin margins, Variolink II/Admira Bond combination showed the lowest microleakage value in dentin (P<.05). CONCLUSIONS: The overall microleakage at the enamel margins was significantly less than at the dentin margins (P<.05). Panavia 21 showed higher microleakage values than Variolink II and RelyX ARC in enamel margins.


Assuntos
Infiltração Dentária/prevenção & controle , Adaptação Marginal Dentária , Adesivos Dentinários/química , Restaurações Intracoronárias/métodos , Cimentos de Resina/química , Análise de Variância , Bis-Fenol A-Glicidil Metacrilato/química , Bis-Fenol A-Glicidil Metacrilato/farmacologia , Cimentos Dentários/química , Cimentos Dentários/classificação , Cimentos Dentários/farmacologia , Esmalte Dentário/efeitos dos fármacos , Porcelana Dentária , Falha de Restauração Dentária , Análise do Estresse Dentário , Adesivos Dentinários/classificação , Adesivos Dentinários/farmacologia , Humanos , Mandíbula , Teste de Materiais , Metacrilatos/química , Metacrilatos/farmacologia , Dente Serotino , Fosfatos/química , Fosfatos/farmacologia , Polietilenoglicóis/química , Polietilenoglicóis/farmacologia , Ácidos Polimetacrílicos/química , Ácidos Polimetacrílicos/farmacologia , Cimentos de Resina/farmacologia , Estatísticas não Paramétricas , Estresse Mecânico
15.
J Prosthet Dent ; 100(2): 99-106, 2008 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-18672126

RESUMO

STATEMENT OF PROBLEM: All-ceramic restorations have been advocated for superior esthetics, and various materials have been used to improve ceramic core strength, but there is a lack of information on how color is affected by different core substructures and fabrication procedures. PURPOSE: The purpose of this study was to evaluate the effects of various dentin ceramic thicknesses and repeated firings on the color of lithium disilicate glass-ceramic (IPS e.max Press) and zirconium-oxide (DC-Zirkon) all-ceramic systems. MATERIAL AND METHODS: Thirty disc-shaped specimens, 4 mm in diameter with a 1-mm core thickness, and 0.5-, 1-, or 1.5-mm dentin ceramic thicknesses, were made from each of 2 ceramic systems (n=10). Repeated firings (3, 5, 7, or 9) were performed, and the color of the specimens was compared with the color after the initial firing. Color differences among ceramic specimens were measured using a spectrophotometer (VITA Easyshade), and data were expressed in CIELAB system coordinates. Repeated measures ANOVA was used to analyze the data (number of firings, ceramic composition, and ceramic thickness) for significant differences. The Tukey HSD test and paired 2-tailed tests were used to perform multiple comparisons (alpha=.05). RESULTS: L*a*b* values of the ceramic systems were affected by the number of firings (3, 5, 7, or 9 firings) (P<.001), ceramic composition (DC-Zirkon or IPS e.max Press) (P<.001), and ceramic thickness (0.5, 1, or 1.5 mm) (P<.001). Significant interactions were present in L*a*b* values between the number of firings and ceramic composition (P<.001) and between the number of firings and ceramic thickness (P<.001). Significant interactions were present between the number of firings and ceramic thickness and ceramic composition (P<.05) in L* and b* values, but not for the a* value (P=.068). As the ceramic thickness increased, significant reductions in L* values (P<.01) were recorded for IPS e.max Press and DC-Zirkon specimens. For IPS e.max Press specimens, there were significant increases in a* and b* values (P<.01). For DC-Zirkon specimens, significant increases in a* values were observed; however, no significant differences were recorded for b* values. CONCLUSIONS: The analysis revealed that there were significant changes in L*a*b* color data as the number of firings increased, which resulted in perceptual color changes in L*a*b* color parameters.


Assuntos
Coroas , Porcelana Dentária , Planejamento de Prótese Dentária , Pigmentação em Prótese , Análise de Variância , Cor , Colorimetria , Técnica de Fundição Odontológica , Dentina/anatomia & histologia , Temperatura Alta , Espectrofotometria , Estatísticas não Paramétricas , Zircônio
16.
J Oral Implantol ; 34(1): 59-62, 2008.
Artigo em Inglês | MEDLINE | ID: mdl-18390245

RESUMO

It can be difficult to achieve superior esthetics in implant-supported fixed partial dentures (FPDs). Zirconia ceramics with high flexural strength and esthetic can be treatment options for implant-supported FPDs. This article describes a simple and reliable method to fabricate a retrievable cemented implant-supported zirconia FPD.


Assuntos
Porcelana Dentária , Planejamento de Prótese Dentária , Prótese Dentária Fixada por Implante , Retenção de Dentadura/instrumentação , Prótese Parcial Fixa , Cimentação , Análise do Estresse Dentário , Retenção de Dentadura/métodos , Humanos , Masculino , Pessoa de Meia-Idade , Zircônio
17.
J Prosthet Dent ; 99(3): 203-8, 2008 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-18319091

RESUMO

STATEMENT OF PROBLEM: Color matching between a restoration and natural teeth is a common clinical problem. Despite careful shade selection, color of the restoration may be affected by fabrication procedures. PURPOSE: The purpose of this study was to determine the color changes of an all-ceramic restoration with 2 different veneering porcelain shades after repeated firings. MATERIAL AND METHODS: Twenty disc-shaped ceramic specimens, 4 mm in diameter with a 1-mm core thickness and 2 different veneering porcelain shades (A1, A3), were fabricated from a zirconia-based porcelain (DC-Zirkon) (n=10). Repeated firings (3, 5, 7, or 9 firings) were performed for the specimens, and color differences (DeltaE) were determined using a spectrophotometer. Repeated measures ANOVA was used to analyze the data (number of firings, veneering porcelain color). The Tukey HSD test and paired 2-tailed tests were performed for multiple comparisons (alpha=.05). RESULTS: The L*a*b* values of the ceramic system were affected by the number of firings (3, 5, 7, or 9) (P<.001) and the veneering porcelain shade (P<.001). Significant interactions were present between the number of firings and veneering porcelain shade for L* (P=.003) and b* (P=.042) values, but not for the a* value (P=.82). An increase in the number of firings of the specimens with both A1 and A3 veneering porcelain shades produced an increase in the L* value, resulting in lighter specimens (P<.001). For both A1 and A3 veneering porcelain shades, the a* value decreased after repeated firings, which resulted in more green specimens (P=.002). The b* value did not change after repeated firings (P=.09) for the A1 veneering porcelain shade; however, it increased for the A3 veneering porcelain shade, which resulted in more yellow specimens (P=.001). CONCLUSIONS: The color of the all-ceramic specimens with different veneering porcelain shades is influenced by repeated firings. However, color changes that occurred are clinically acceptable.


Assuntos
Porcelana Dentária/química , Planejamento de Prótese Dentária/métodos , Facetas Dentárias , Pigmentação em Prótese/métodos , Cor , Materiais Dentários/química , Temperatura Alta , Humanos , Teste de Materiais , Espectrofotometria , Zircônio/química
18.
Int J Prosthodont ; 21(6): 509-10, 2008.
Artigo em Inglês | MEDLINE | ID: mdl-19149067

RESUMO

Because of their strength, zirconia ceramics may be used to restore removable partial denture abutments. This carries the advantages of elimination of the galvanic current between primary and secondary copings, along with thermal protection of abutment teeth. This article describes the fabrication of zirconium primary copings to provide retention for a mandibular telescopic overdenture.


Assuntos
Porcelana Dentária , Planejamento de Dentadura , Retenção de Dentadura/instrumentação , Revestimento de Dentadura , Ligas Dentárias/efeitos adversos , Eletrogalvanismo Intrabucal , Eletrólise , Feminino , Humanos , Mandíbula , Pessoa de Meia-Idade , Zircônio
19.
J Oral Implantol ; 33(5): 297-304, 2007.
Artigo em Inglês | MEDLINE | ID: mdl-17987863

RESUMO

This article describes the fabrication of implant-supported overdentures and removable partial dentures attached to anterior fixed partial dentures utilizing impression techniques to transfer the position of implants and record soft tissue areas in a functional state.


Assuntos
Técnica de Moldagem Odontológica , Planejamento de Prótese Dentária , Prótese Dentária Fixada por Implante , Idoso , Implantação Dentária Endóssea , Retenção em Prótese Dentária/instrumentação , Revestimento de Dentadura , Prótese Parcial Fixa , Prótese Parcial Removível , Feminino , Humanos , Masculino , Pessoa de Meia-Idade
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