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1.
Int J Periodontics Restorative Dent ; 43(2): e111-e115, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-37232690

RESUMO

Implant mandibular complete overdenture (IMCO) is a reliable prosthetic option. However, clinical and laboratory complications are associated with these restorations if not executed properly. In this clinical report, the combination of analog and digital workflow helps minimize the chairside time with fewer visits, which improves efficiency and patient satisfaction. Int J Periodontics Restorative Dent 2023;43:e111-e115. doi: 10.11607/prd.5975.


Assuntos
Implantes Dentários , Humanos , Titânio , Fluxo de Trabalho , Revestimento de Dentadura , Prótese Dentária Fixada por Implante
2.
Braz. j. biol ; 83: e247676, 2023. tab, graf
Artigo em Inglês | LILACS, VETINDEX | ID: biblio-1345527

RESUMO

Abstract Development of insecticides resistance mainly hinge with managements techniques for the control of Jassid, Amrasca biguttutla biguttutla. Five insecticides were applied against field collected and laboratory rared jassid populations during the years of 2017 to 2019 to profile their resistance level against field population of jassid through leaf dip method. Very low resistance level was found in jassid against confidor whereas high level of resistance was observed by pyriproxyfen against other test insecticides. Gradual resistance was observed against diafenthiuron. It is concluded that for the management of Jassid repetition of same insecticide should be avoided. The use of confidor may be reduced to overcome resistance against Jassid.


Resumo Desenvolvimento da resistência a inseticidas principalmente em dobradiça com técnicas de manejo para o controle de jassid, Amrasca biguttutla biguttutla. Cinco inseticidas foram aplicados contra populações de jassídeos coletados em campo e em laboratório durante os anos de 2017 a 2019 para traçar o perfil de seu nível de resistência contra populações de jassídeos em campo através do método de imersão nas folhas. Nível de resistência muito baixo foi encontrado em jassid contra confidor, enquanto alto nível de resistência foi observado por piriproxifeno contra outros inseticidas de teste. Resistência gradual foi observada contra o diafenthiuron. Conclui-se que, para o manejo do jassid, a repetição do mesmo inseticida deve ser evitada. O uso de confidor pode ser reduzido para superar a resistência contra jassid.


Assuntos
Animais , Hemípteros , Inseticidas/farmacologia , Resistência a Inseticidas , Laboratórios
3.
Braz. j. biol ; 83: 1-6, 2023. ilus, tab, graf
Artigo em Inglês | LILACS, VETINDEX | ID: biblio-1468981

RESUMO

Development of insecticides resistance mainly hinge with managements techniques for the control of Jassid, Amrasca biguttutla biguttutla. Five insecticides were applied against field collected and laboratory rared jassid populations during the years of 2017 to 2019 to profile their resistance level against field population of jassid through leaf dip method. Very low resistance level was found in jassid against confidor whereas high level of resistance was observed by pyriproxyfen against other test insecticides. Gradual resistance was observed against diafenthiuron. It is concluded that for the management of Jassid repetition of same insecticide should be avoided. The use of confidor may be reduced to overcome resistance against Jassid.


Desenvolvimento da resistência a inseticidas principalmente em dobradiça com técnicas de manejo para o controle de jassid, Amrasca biguttutla biguttutla. Cinco inseticidas foram aplicados contra populações de jassídeos coletados em campo e em laboratório durante os anos de 2017 a 2019 para traçar o perfil de seu nível de resistência contra populações de jassídeos em campo através do método de imersão nas folhas. Nível de resistência muito baixo foi encontrado em jassid contra confidor, enquanto alto nível de resistência foi observado por piriproxifeno contra outros inseticidas de teste. Resistência gradual foi observada contra o diafenthiuron. Conclui-se que, para o manejo do jassid, a repetição do mesmo inseticida deve ser evitada. O uso de confidor pode ser reduzido para superar a resistência contra jassid.


Assuntos
Animais , Hemípteros , Inseticidas , Resistência a Inseticidas
4.
Braz. j. biol ; 832023.
Artigo em Inglês | LILACS-Express | LILACS, VETINDEX | ID: biblio-1469197

RESUMO

Abstract Development of insecticides resistance mainly hinge with managements techniques for the control of Jassid, Amrasca biguttutla biguttutla. Five insecticides were applied against field collected and laboratory rared jassid populations during the years of 2017 to 2019 to profile their resistance level against field population of jassid through leaf dip method. Very low resistance level was found in jassid against confidor whereas high level of resistance was observed by pyriproxyfen against other test insecticides. Gradual resistance was observed against diafenthiuron. It is concluded that for the management of Jassid repetition of same insecticide should be avoided. The use of confidor may be reduced to overcome resistance against Jassid.


Resumo Desenvolvimento da resistência a inseticidas principalmente em dobradiça com técnicas de manejo para o controle de jassid, Amrasca biguttutla biguttutla. Cinco inseticidas foram aplicados contra populações de jassídeos coletados em campo e em laboratório durante os anos de 2017 a 2019 para traçar o perfil de seu nível de resistência contra populações de jassídeos em campo através do método de imersão nas folhas. Nível de resistência muito baixo foi encontrado em jassid contra confidor, enquanto alto nível de resistência foi observado por piriproxifeno contra outros inseticidas de teste. Resistência gradual foi observada contra o diafenthiuron. Conclui-se que, para o manejo do jassid, a repetição do mesmo inseticida deve ser evitada. O uso de confidor pode ser reduzido para superar a resistência contra jassid.

5.
Medicina (Kaunas) ; 58(10)2022 09 25.
Artigo em Inglês | MEDLINE | ID: mdl-36295507

RESUMO

Objective: The aim of the study was to systematically review the overall outcomes of studies comparing the misfit of yttria-stabilized zirconia (Y-TZP) CAD-CAM implant-supported frameworks with frameworks fabricated with other materials and techniques. Methods: An electronic literature search of English literature was performed using Google Scholar, Scopus, Web of Science, MEDLINE (OVID), EMBASE, and PubMed, using predetermined inclusion criteria. Specific terms were utilized in conducting a search from the inception of the respective database up to May 2022. After the search strategy was applied, the data were extracted and the results were analyzed. The focused question was: Is the misfit of the implant-supported zirconia CAD-CAM framework lower than that of non-Y-TZP implant-supported fixed restorations? Results: Eleven articles were included for qualitative assessment and critical appraisal in this review. In the included studies, Y-TZP CAD-CAM implant-supported frameworks were compared to Titanium (Ti), Ni-Cr, Co-Cr, PEEK and high-density polymer, and cast and CAD-CAM frameworks. The studies used scanning electron microscopy, one-screw tests, digital or optical microscopy, 3D virtual assessment, and replica techniques for analyzing the misfit of frameworks. Six studies showed comparable misfits among the Y-TZP CAD-CAM frameworks and the controls. Three studies showed higher misfits for the Y-TZP CAD-CAM frameworks, whereas two studies reported lower misfits for Y-TZP CAD-CAM implant frameworks compared to controls. Conclusion: Y-TZP CAD-CAM implant-supported frameworks have comparable misfits to other implant-supported frameworks. However, due to heterogeneity in the methodologies of the included studies, the overall numerical misfit of the frameworks assessed in the reviewed studies is debatable.


Assuntos
Titânio , Zircônio , Humanos , Desenho Assistido por Computador , Polímeros
6.
Materials (Basel) ; 15(17)2022 Sep 05.
Artigo em Inglês | MEDLINE | ID: mdl-36079529

RESUMO

This study aimed to measure the effect of storage environment on the hardness, surface roughness and wear ability of CAD/CAM resin-matrix ceramics. A total of 200 rectangular-shaped specimens were obtained by sectioning 5 CAD/CAM blocks; Crystal Ultra (CU), Vita Enamic (VE), Lava Ultimate (LU), Cerasmart (CS) and Vita blocks Mark II (MII). Microhardness and surface roughness were measured at baseline and after 7 days of immersion either in saliva or cola (n = 10). The wear ability of the CAD/CAM materials against steatite-ceramics antagonist was determined using a chewing simulator. The data were statistically analyzed using factorial ANOVA followed by post hoc Bonferroni multiple comparison tests (p < 0.05). The independent factors significantly influenced the microhardness and surface roughness (p < 0.05). The highest VHN was observed in MII at baseline (586.97 ± 13.95), while CU showed the lowest VHN after 7 days of immersion in cola (68.3 ± 1.89). On the contrary, the highest Ra was observed after 120,000 chewing cycles for the VE specimens (1.09 ± 0.43 µm) immersed in cola, while LU showed the lowest Ra at baseline (0.07 ± 0.01 µm). The highest % mass loss of the antagonist was observed with MII immersed in cola (1.801%), while CS demonstrated the lowest % mass loss of 0.004% and 0.007% in AS and cola, respectively. This study confirms that the surface properties of tested CAD/CAM materials are susceptible to degradation in an acidic environment except for hardness and wear of CS material.

8.
Braz J Biol ; 83: e247676, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-34669912

RESUMO

Development of insecticides resistance mainly hinge with managements techniques for the control of Jassid, Amrasca biguttutla biguttutla. Five insecticides were applied against field collected and laboratory rared jassid populations during the years of 2017 to 2019 to profile their resistance level against field population of jassid through leaf dip method. Very low resistance level was found in jassid against confidor whereas high level of resistance was observed by pyriproxyfen against other test insecticides. Gradual resistance was observed against diafenthiuron. It is concluded that for the management of Jassid repetition of same insecticide should be avoided. The use of confidor may be reduced to overcome resistance against Jassid.


Assuntos
Hemípteros , Inseticidas , Animais , Resistência a Inseticidas , Inseticidas/farmacologia , Laboratórios
9.
J Dent ; 113: 103795, 2021 10.
Artigo em Inglês | MEDLINE | ID: mdl-34481932

RESUMO

OBJECTIVE: With the emergence of graduates from all government and private-funded dental colleges in Saudi Arabia (SA), it is pressing to explore the graduates' satisfaction with the dental undergraduate education and training they received. The aim of the present study was to investigate the graduates' satisfaction with their education and training according to college funding arrangements (government vs private-funded) and time since establishment (established- >15 years vs new-<15 years). METHODS: A piloted, electronic questionnaire was emailed to all the members of the Saudi Dental Society who had graduated from government and and private dental colleges in SA (2,185 registrants). RESULTS: The response rate was 36.4%, with 580 government-funded college graduates (72.9%) and 216 private college graduates (27.1%) having completed and returned the questionnaire. The distribution of participants between established and new colleges was 'established' 396 (49.8%) and 'new' 400 (50.2%). Levels of dissatisfaction were recorded for graduates from established and new, government-funded and private colleges. The levels of dissatisfaction were greater amongst the graduates of established and government-funded colleges. CONCLUSION: The findings of the present study indicate concerning levels of dissatisfaction with important aspects of dental education in SA. It is suggested that there is a pressing need for more integration of basic and clinical sciences and an emphasis on hands-on training. National coordination of arrangements for dental curricula could make a major contribution to addressing the problems identified.


Assuntos
Currículo , Satisfação Pessoal , Humanos , Arábia Saudita , Estudantes , Inquéritos e Questionários , Universidades
10.
Antibiotics (Basel) ; 10(6)2021 Jun 16.
Artigo em Inglês | MEDLINE | ID: mdl-34208591

RESUMO

Biofilms not only protect bacteria and Candida species from antibiotics, but they also promote the emergence of drug-resistant strains, making eradication more challenging. As a result, novel antimicrobial agents to counteract biofilm formation are desperately needed. In this study, Terminalia catappa leaf extract (TCE) was used to optimize the TCE-capped silver nanoparticles (TCE-AgNPs) via a one-pot single-step method. Varied concentrations of TCE have yielded different sized AgNPs. The physico-chemical characterization of TCE-AgNPs using UV-Vis, SEM, TEM, FTIR, and Raman spectroscopy have confirmed the formation of nanostructures, their shape and size and plausible role of TCE bio-active compounds, most likely involved in the synthesis as well as stabilization of NPs, respectively. TCE-AgNPs have been tested for antibiofilm and antimicrobial activity against multidrug-resistant Pseudomonas aeruginosa (MDR-PA), methicillin-resistant Staphylococcus aureus (MRSA), and Candida albicans using various microbiological protocols. TCE-Ag-NPs-3 significantly inhibits biofilm formation of MDR-PA, MRSA, and C. albicans by 73.7, 69.56, and 63.63%, respectively, at a concentration of 7.8 µg/mL, as determined by crystal violet microtiter assay. Furthermore, SEM micrograph shows that TCE-AgNPs significantly inhibit the colonization and adherence of biofilm forming cells; individual cells with loss of cell wall and membrane integrity were also observed, suggesting that the biofilm architecture and EPS matrix were severely damaged. Moreover, TEM and SEM images showed that TCE-AgNPs brutally damaged the cell wall and membranes of MDR-PA, MRSA, and C. albicans. Additionally, extreme ultrastructural changes such as deformation, disintegration, and separation of cell wall and membrane from the cells, have also been observed, indicating significant loss of membrane and cell wall integrity, which eventually led to cell death. Overall, the research revealed a simple, environmentally friendly, and low-cost method for producing colloidal TCE-AgNPs with promising applications in advanced clinical settings against broad-spectrum biofilm-forming antibiotic-resistant bacteria and candida strains.

11.
J Prosthodont ; 27(8): 681-687, 2018 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-28118512

RESUMO

Patients with Down syndrome can present with a variety of oral manifestations such as hypodontia, periodontal disease, premature tooth loss, reduced salivary flow, crowding of teeth in both arches, and decreased occlusal vertical dimension. The intellectual ability of people with Down syndrome varies widely. They present with a mild-to-moderate intellectual disability that restricts their ability to communicate and adjust to their environment, which can add complexity in the overall dental treatment. There is little information in the literature regarding the prosthodontic rehabilitation for patients with Down syndrome in combination with dental implant placement. An implant-assisted removable partial dental prosthesis can be a cost-effective treatment alternative for carefully chosen patients with Down syndrome. This article presents the treatment of a 44-year-old male patient with Down syndrome and a moderate intellectual disability who presented with congenital and acquired tooth loss with significant occlusal discrepancies. The treatment included a prosthodontic approach that used a single dental implant, which will be described and illustrated in this article.


Assuntos
Prótese Dentária Fixada por Implante , Prótese Parcial Removível , Síndrome de Down/complicações , Adulto , Implantação Dentária Endóssea/métodos , Prótese Dentária Fixada por Implante/métodos , Planejamento de Dentadura , Humanos , Masculino , Reabilitação Bucal/métodos , Perda de Dente/cirurgia
12.
J Prosthet Dent ; 119(6): 873-878, 2018 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-29150132

RESUMO

Ectodermal dysplasia is a rare, hereditary, congenital disease that affects the normal development of certain tissues and structures of ectodermal origin. The disease is manifested to different degrees of severity and may involve the nose, eyes, hair, nails, sweat glands, and enamel. This report describes a 14-year-old boy with ectodermal dysplasia, rehabilitated with monolithic, multichromatic maxillary and mandibular computer-aided design and computer-aided manufacturing (CAD-CAM) acrylic resin complete overdentures.


Assuntos
Revestimento de Dentadura , Displasia Ectodérmica/reabilitação , Prostodontia/métodos , Resinas Acrílicas , Adolescente , Humanos , Masculino , Desenho de Aparelho Ortodôntico
13.
Annu Int Conf IEEE Eng Med Biol Soc ; 2017: 572-575, 2017 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-29059937

RESUMO

Dual high and low energy images of Dual Energy X-ray Absorptiometry (DEXA) suffer from noises due to the use of weak amount of X-rays. Denoising these DEXA images could be a key process to enhance and improve a Bone Mineral Density (BMD) map which is derived from a pair of high and low energy images. This could further improve the accuracy of diagnosis of bone fractures, osteoporosis, and etc. In this paper, we present a denoising technique for dual high and low energy images of DEXA via non-local means filter (NLMF). The noise of dual DEXA images is modeled based on both source and detector noises of a DEXA system. Then, the parameters of the proposed NLMF are optimized for denoising utilizing the experimental data from uniform phantoms. The optimized NLMF is tested and verified with the DEXA images of the uniform phantoms and real human spine. The quantitative evaluation shows the improvement of Signal-to-Noise Ratio (SNR) for the high and low phantom images on the order of 30.36% and 27.02% and for the high and low real spine images on the order of 22.28% and 33.43%, respectively. Our work suggests that denoising via NLMF could be a key preprocessing process for clinical DEXA imaging.


Assuntos
Absorciometria de Fóton , Imagens de Fantasmas , Razão Sinal-Ruído
14.
J Prosthodont ; 26(7): 622-627, 2017 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-28865133

RESUMO

Telescopic crown attachments have been successfully used in completely and partially edentulous patients. This type of attachment provides retention, support, and stability with optimal hygiene for the removable dental prosthesis (RDP). With the emergence of CAD/CAM technology, telescopic crown attachments can be virtually designed and milled precisely to ensure a passive fit of the attachment parts and maximal functionality of the RDP. This article reviews both the clinical outcome and prosthodontic rehabilitation of telescopic crown attachments of an edentulous ectodermal dysplasia patient with solitary rigid conical telescopic crown attachments.


Assuntos
Anodontia/reabilitação , Coroas , Prótese Dentária Fixada por Implante , Prótese Total , Revestimento de Dentadura , Displasia Ectodérmica/reabilitação , Androsterona/análogos & derivados , Anodontia/etiologia , Planejamento de Dentadura/métodos , Diterpenos , Displasia Ectodérmica/complicações , Humanos , Masculino , Pessoa de Meia-Idade
15.
J Neuroendocrinol ; 28(5)2016 05.
Artigo em Inglês | MEDLINE | ID: mdl-26929121

RESUMO

Oestrogens influence memory system bias in female rats such that high levels of oestrogen are associated with place (or spatial) memory use, and low oestrogen levels with response (or habitual) memory use. Moreover, striatal-dependent response memory is sensitive to dopamine transmission in the dorsal striatum, and oestrogens have been shown to affect dopamine release in that brain area. In the present study, the effects of oestrogens and dopamine transmission on multiple memory system bias were explored in ovariectomised rats receiving low or high 17ß-oestradiol replacement under saline, autoreceptor-activating doses of the dopamine D2 receptor agonist, apomorphine (50 and 80 µg/kg), or amphetamine (0.5 mg/kg) administration. Furthermore, dorsal striatal dopamine release was measured after administration of the same drug conditions using in vivo microdialysis. As expected, high oestradiol rats predominantly used place memory, whereas the opposite pattern was observed in low oestradiol rats. However, the high apomorphine dose statistically significantly altered memory bias in high oestradiol rats from predominant place to predominant response memory, with a similar trend in the low apomorphine dose and the amphetamine group. There was no effect of drugs on memory bias in low oestradiol rats. Rats with high oestradiol replacement receiving amphetamine exhibited greater dorsal striatal dopamine release than low oestradiol replacement rats, and this difference was amplified in the right hemisphere. Furthermore, a logistic regression analysis revealed that oestradiol, but not dorsal striatal dopamine levels, significantly predicted response memory bias. These findings provide further evidence that oestradiol modulates memory system bias, and also that memory bias is changed by systemic apomorphine administration. However, although oestradiol affects dopamine transmission in the dorsal striatum in a lateralised manner, this does not predict memory system bias.


Assuntos
Corpo Estriado/fisiologia , Dopamina/metabolismo , Estradiol/fisiologia , Memória/fisiologia , Anfetamina/administração & dosagem , Animais , Apomorfina/administração & dosagem , Corpo Estriado/efeitos dos fármacos , Corpo Estriado/metabolismo , Estradiol/administração & dosagem , Feminino , Aprendizagem em Labirinto/efeitos dos fármacos , Aprendizagem em Labirinto/fisiologia , Memória/efeitos dos fármacos , Ovariectomia , Ratos Sprague-Dawley , Receptores de Dopamina D2/agonistas , Receptores de Dopamina D2/fisiologia , Memória Espacial/efeitos dos fármacos , Memória Espacial/fisiologia
16.
Behav Brain Res ; 205(1): 115-22, 2009 Dec 14.
Artigo em Inglês | MEDLINE | ID: mdl-19643146

RESUMO

A growing body of literature suggests that sex differences exist in both rodents and humans in terms of the central processing of stress and emotion, and an important factor in this regard may involve differential hemispheric specialization. The amygdala has been shown to be functionally asymmetrical in both rats and humans and its involvement in stress and emotion processing is well documented. Given that amygdala function is importantly modulated by dopamine (DA), the present study examined the effects of left vs. right unilateral DAergic depletion targeting the basolateral amygdala in male and female rats. We examined behaviour in the elevated plus maze over two consecutive days, and plasma adrenocorticotropic hormone (ACTH) levels in response to a separate 30min restraint stress. Overall, females showed significantly more exploration of open arms of the plus maze than males, while not differing in general activity reflected in closed arm entries. Significant SexxHemisphere interactions were observed for all measures related to open arm exploration, as right amygdala DA depletion produced an anxiolytic effect in males, increasing open arm exploration, but reduced this behaviour in females. Moreover, open arm exploration was greatly reduced on the second maze exposure in males, but unchanged in females. A SexxHemisphere interaction was also found for plasma ACTH levels. It is suggested that the role of amygdala DA on stress-related behaviour and physiology reflects inherent differences in amygdala function dependent on both sex and hemisphere.


Assuntos
Tonsila do Cerebelo/fisiopatologia , Dopamina/deficiência , Lateralidade Funcional , Aprendizagem em Labirinto/fisiologia , Caracteres Sexuais , Estresse Psicológico/fisiopatologia , Hormônio Adrenocorticotrópico/sangue , Tonsila do Cerebelo/fisiologia , Animais , Ansiedade/fisiopatologia , Dopamina/metabolismo , Comportamento Exploratório/fisiologia , Feminino , Masculino , Ratos , Ratos Long-Evans , Restrição Física , Estresse Psicológico/sangue , Fatores de Tempo
17.
J Pak Med Assoc ; 54(8): 423-7, 2004 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-15461211

RESUMO

OBJECTIVE: To review and audit our experience with closed intramedullary interlocking nailing for acute femoral shaft fractures. METHODS: All patients admitted to The Aga Khan University Hospital, over the last six years and with a minimum follow-up of twelve months, with acute fractures of the femoral shaft were included in the study. All patients treated for established non-unions and infections or with pathological fractures were excluded from the study. RESULTS: There were 89 fractures, 74% of whom were closed and 50% were associated with other orthopedic injuries. Most of these were younger patients involved in high velocity road traffic accidents. The union rate was 88% with 4.4% of fractures going into non-union. The remaining 8% of the fractures went into a phase of delayed union, but ultimately united, making the overall success rate to be 95.6%. The mean time for union was 11.5 weeks. At the final clinical follow-up, 4% of the patients had minor pain, 7% had limp, 4% had leg length discrepancy of more than 2 cm and 4% had decreased range of motion at the hip or knee joints. We had a 4% rate of superficial infection. There were 3 cases of pudendal nerve neuropraxia and 2 cases of deep vein thrombosis. CONCLUSION: Intramedullary Interlocking nailing is a safe and effective treatment modality for acute fractures of the femoral shaft. Proper surgical decision making regarding static versus dynamic mode of locking can avoid problems of delayed union.


Assuntos
Pinos Ortopédicos , Fraturas do Fêmur/cirurgia , Fixação Intramedular de Fraturas , Doença Aguda , Adolescente , Adulto , Idoso , Feminino , Fixação de Fratura/métodos , Consolidação da Fratura , Humanos , Masculino , Pessoa de Meia-Idade , Estudos Retrospectivos
19.
Laryngoscope ; 109(2 Pt 1): 181-5, 1999 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-10890762

RESUMO

OBJECTIVE: Auditory neuropathy is a recently described clinical entity characterized by sensorineural hearing loss in which the auditory evoked potential (ABR) is absent but otoacoustic emissions are present. This suggests a central locus for the associated hearing loss. In this study the results observed in a child with auditory neuropathy who received a cochlear implant are presented and compared with those of a matched group of children who were recipients of implants. METHODS: A single-subject, repeated-measures design, evaluating closed-set and open-set word recognition abilities was used to assess the subject and a control group of matched children with implants who had also experienced a progressive sensorineural hearing loss. RESULTS: The subject demonstrated improvements in vowel recognition (82% correct) by 1 year after implantation, which were only slightly lower than the control group. Consonant recognition and open-set word recognition scores were significantly lower. CONCLUSION: Caution should be exercised when considering cochlear implantation in children with auditory neuropathy. As with conventional hearing aids, less than optimal results may be seen.


Assuntos
Doenças Cocleares/complicações , Doenças Cocleares/fisiopatologia , Implante Coclear , Perda Auditiva Neurossensorial , Audiometria de Tons Puros/métodos , Pré-Escolar , Progressão da Doença , Potenciais Evocados Auditivos do Tronco Encefálico/fisiologia , Seguimentos , Ataxia de Friedreich/complicações , Ataxia de Friedreich/diagnóstico , Perda Auditiva Neurossensorial/etiologia , Perda Auditiva Neurossensorial/fisiopatologia , Perda Auditiva Neurossensorial/cirurgia , Humanos , Masculino , Fonética , Índice de Gravidade de Doença , Percepção da Fala/fisiologia
20.
Ear Hear ; 19(6): 434-49, 1998 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-9867292

RESUMO

OBJECTIVES: 1) To evaluate transient evoked otoacoustic emission (TEOAE) test performance when measurements are made under routine clinical conditions. 2) To evaluate TEOAE test performance as a function of frequency and as a function of the magnitude of hearing loss. 3) To compare test performance using univariate and multivariate approaches to data analyses. 4) To provide a means of interpreting clinical TEOAE measurements. DESIGN: TEOAEs were measured in 452 ears of 246 patients. All measurements were made after acoustic immittance assessments, which were used to demonstrate that middle-ear function was normal at the time of the TEOAE test. TEOAE amplitudes and signal to noise ratios (SNRs), analyzed into octave bands centered at 1, 2, and 4 kHz, were compared with the pure-tone threshold at the same frequencies. Data were analyzed with clinical decision theory, cumulative distributions, discriminant analyses, and logistic regressions. RESULTS: Using univariate analysis techniques, TEOAEs accurately identified auditory status at 2 and 4 kHz but were less accurate at 1 kHz. Test performance was best when audiometric thresholds between 20 and 30 dB HL were used as the criteria for normal hearing. TEOAE SNR resulted in better test performance than did TEOAE amplitude alone; this effect decreased as frequency increased. Multivariate analysis methods resulted in better separation between normal and impaired ears than did univariate approaches, which relied on only TEOAE amplitude or SNR when test frequency band and audiometric frequency were the same. This improvement in test performance was greatest at 1 kHz, decreased as frequency increased, and was negligible at 4 kHz. CONCLUSIONS: TEOAEs can be used to identify hearing loss in children under routine clinical conditions. Univariate tests accurately identified auditory status at mid and high frequencies but performed more poorly at lower frequencies. The decrease in performance as frequency decreases may be a result of increased noise at lower frequencies but also may be due to properties of the measurement paradigm ("QuickScreen," high-pass filter at 0.8 kHz), which would not be ideal for recording energy around 1 kHz. The improvement in test performance when SNR was used and the interaction of this effect with frequency, however, would be consistent with the view that test performance in lower frequencies is at least partially influenced by the level of background noise. Multivariate analysis techniques improved test performance compared with the more traditional univariate approaches to data analysis. An approach is provided that allows one to assign measured TEOAE amplitudes, SNRs, or outputs from multivariate analyses to one of three categories: response properties consistent with normal hearing; results consistent with hearing loss; hearing status undetermined.


Assuntos
Cóclea/fisiologia , Perda Auditiva Neurossensorial/diagnóstico , Estimulação Acústica , Adolescente , Adulto , Limiar Auditivo , Audição/fisiologia , Humanos , Ruído
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