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1.
MMWR Morb Mortal Wkly Rep ; 72(15): 391-397, 2023 Apr 14.
Artigo em Inglês | MEDLINE | ID: mdl-37053125

RESUMO

Since the Global Polio Eradication Initiative (GPEI) began in 1988, the number of wild poliovirus (WPV) cases has declined by >99.99%. Five of the six World Health Organization (WHO) regions have been certified free of indigenous WPV, and WPV serotypes 2 and 3 have been declared eradicated globally (1). WPV type 1 (WPV1) remains endemic only in Afghanistan and Pakistan (2,3). Before the outbreak described in this report, WPV1 had not been detected in southeastern Africa since the 1990s, and on August 25, 2020, the WHO African Region was certified free of indigenous WPV (4). On February 16, 2022, WPV1 infection was confirmed in one child living in Malawi, with onset of paralysis on November 19, 2021. Genomic sequence analysis of the isolated poliovirus indicated that it originated in Pakistan (5). Cases were subsequently identified in Mozambique. This report summarizes progress in the outbreak response since the initial report (5). During November 2021-December 2022, nine children and adolescents with paralytic polio caused by WPV1 were identified in southeastern Africa: one in Malawi and eight in Mozambique. Malawi, Mozambique, and three neighboring countries at high risk for WPV1 importation (Tanzania, Zambia, and Zimbabwe) responded by increasing surveillance and organizing up to six rounds of national and subnational polio supplementary immunization activities (SIAs).* Although no cases of paralytic WPV1 infection have been reported in Malawi since November 2021 or in Mozambique since August 2022, undetected transmission might be ongoing because of poliovirus surveillance gaps and testing delays. Efforts to further enhance poliovirus surveillance sensitivity, improve SIA quality, and strengthen routine immunization are needed to ensure that WPV1 transmission has been interrupted within 12 months of the first case, thereby preserving the WHO African Region's WPV-free status.


Assuntos
Poliomielite , Poliovirus , Criança , Adolescente , Humanos , Poliovirus/genética , Vigilância da População , Poliomielite/epidemiologia , Poliomielite/prevenção & controle , Surtos de Doenças , Malaui , Vacina Antipólio Oral , Programas de Imunização , Erradicação de Doenças
2.
Dent Traumatol ; 39(2): 101-108, 2023 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-36436198

RESUMO

Sports mouthguards are proven devices that reduce both the probability of and damage to orofacial tissues. While commonly used, clinicians may be unaware of the different sports mouthguard materials, proposed fabrication techniques, design recommendations, and newer digital fabrication methods. An overview of existing sports mouthguard standards is presented. It identifies that identify that the present requirements, while historically chosen in good faith, appear to be arbitrarily selected and not from clinical evidence-based derived data. In addition, identified sports mouthguard heterogeneous testing and data acquisition methods distinguishes that little possibility is afforded for the correlation of results. Furthermore, updated evidence with concussion prevention and/or alleviation is presented with evidence provided by sports mouthguard imbedded technology. The need for continued research is stressed to provide evidence-based data for concussion alleviation/prevention, digital fabrication methods and materials, and clinically based information for the revision of existing standards.


Assuntos
Traumatismos em Atletas , Concussão Encefálica , Protetores Bucais , Esportes , Traumatismos Dentários , Humanos , Traumatismos em Atletas/prevenção & controle , Traumatismos Dentários/prevenção & controle , Desenho de Equipamento
3.
J Med Virol ; 93(8): 4720-4728, 2021 08.
Artigo em Inglês | MEDLINE | ID: mdl-33458840

RESUMO

Enteroviruses (EVs) are RNA viruses that can cause many clinical syndromes including acute flaccid paralysis (AFP). Within the global polio laboratory network, EVs are categorized either as polioviruses or non-polio enteroviruses (NPEVs). Specific NPEVs have been described in polio-like residual paralytic events in AFP patients. Retrospective analysis of 112 NPEV isolates from AFP patients was performed and thirty one NPEV types were identified of which 91% were Enterovirus B and 9% were Enterovirus A species. The NPEVs were distributed across the country with most patients in the eastern region (41/89; 46.1%). The highest proportion of patients were children less than 5 years (77/89; 86.5%) and male patients were more common (54/89; 60.7%). Echovirus 11 (11/89; 12.4%) was frequently observed and phylogenetic analysis of these sequences revealed high diversity. Coxsackievirus B5 (CV-B5), CV-B6, E21, and EV-B69 were only seen in patients with residual paralysis. Analyses of the EV-A71 sequence indicated a unique genogroup.


Assuntos
Viroses do Sistema Nervoso Central/virologia , Infecções por Enterovirus/virologia , Enterovirus/genética , Enterovirus/isolamento & purificação , Genótipo , Mielite/virologia , Doenças Neuromusculares/virologia , Filogenia , Adolescente , Viroses do Sistema Nervoso Central/epidemiologia , Criança , Pré-Escolar , Estudos Transversais , Enterovirus/classificação , Infecções por Enterovirus/epidemiologia , Monitoramento Epidemiológico , Fezes/virologia , Feminino , Variação Genética , Humanos , Masculino , Mielite/epidemiologia , Doenças Neuromusculares/epidemiologia , Poliomielite/virologia , Estudos Retrospectivos , Análise de Sequência de DNA , Fatores Sexuais , Uganda/epidemiologia
4.
Clin Infect Dis ; 70(1): 132-135, 2020 01 01.
Artigo em Inglês | MEDLINE | ID: mdl-31086993

RESUMO

Primary B-cell immunodeficiencies are risk factors for the generation of vaccine-derived polioviruses. We report immunodeficiency-associated vaccine-derived poliovirus serotype 3 in an 11-week-old boy with X-linked agammaglobulinemia. Unique characteristics of this case include early age of presentation, high viral evolutionary rate, and the child's perinatal exposure to human immunodeficiency virus.


Assuntos
Agamaglobulinemia , Poliomielite , Poliovirus , Criança , Doenças Genéticas Ligadas ao Cromossomo X , HIV/genética , Humanos , Masculino , Poliovirus/genética , Vacina Antipólio Oral/efeitos adversos , Sorogrupo
5.
Drug Chem Toxicol ; 42(4): 403-408, 2019 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-29722548

RESUMO

Novel-substituted phenoxyalkyl pyridinium oxime acetylcholinesterase (AChE) reactivators (US patent 9,227,937) that showed convincing evidence of penetration into the brains of intact rats were developed by our laboratories. The oximes separated into three groups based on their levels of brain AChE reactivation following exposure of rats to the sarin surrogate nitrophenyl isopropyl methylphosphonate (NIMP). P-glycoprotein (P-gp) is a major blood-brain barrier (BBB) transporter and requires ATP for efflux. To determine if P-gp affinity screening could be used to reduce animal use, we measured in vitro oxime-stimulated ATPase activity to see if the in vivo reactivation efficacies related to the oximes' functions as P-gp substrates. High efficacy oximes were expected to be poor P-gp substrates, thus remaining in the brain longer. The high efficacy oximes (24-35% brain AChE reactivation) were worse P-gp substrates than the low efficacy oximes (0-7% brain AChE reactivation). However, the oxime group with medium in vivo reactivation of 10-17% were even worse P-gp substrates than the high efficacy group so their reactivation ability was not reflected by P-gp export. The results suggest that in vitro P-gp ATPase activity can remove the low efficacy oximes from in vivo testing, but is not sufficient to differentiate between the top two tiers.


Assuntos
Membro 1 da Subfamília B de Cassetes de Ligação de ATP/metabolismo , Acetilcolinesterase/metabolismo , Reativadores da Colinesterase/farmacologia , Oximas/farmacologia , Compostos de Piridínio/farmacologia , Alternativas aos Testes com Animais , Animais , Transporte Biológico , Barreira Hematoencefálica/enzimologia , Barreira Hematoencefálica/metabolismo , Membrana Celular/enzimologia , Membrana Celular/metabolismo , Reativadores da Colinesterase/metabolismo , Técnicas In Vitro , Microssomos/enzimologia , Microssomos/metabolismo , Estrutura Molecular , Oximas/metabolismo , Compostos de Piridínio/metabolismo , Ratos , Especificidade por Substrato
6.
Emerg Infect Dis ; 24(1): 65-74, 2018 01.
Artigo em Inglês | MEDLINE | ID: mdl-29260690

RESUMO

During the 2014-2015 outbreak of Ebola virus disease in Guinea, 13 type 2 circulating vaccine-derived polioviruses (cVDPVs) were isolated from 6 polio patients and 7 healthy contacts. To clarify the genetic properties of cVDPVs and their emergence, we combined epidemiologic and virologic data for polio cases in Guinea. Deviation of public health resources to the Ebola outbreak disrupted polio vaccination programs and surveillance activities, which fueled the spread of neurovirulent VDPVs in an area of low vaccination coverage and immunity. Genetic properties of cVDPVs were consistent with their capacity to cause paralytic disease in humans and capacity for sustained person-to-person transmission. Circulation ceased when coverage of oral polio vaccine increased. A polio outbreak in the context of the Ebola virus disease outbreak highlights the need to consider risks for polio emergence and spread during complex emergencies and urges awareness of the challenges in polio surveillance, vaccination, and diagnosis.


Assuntos
Doença pelo Vírus Ebola/complicações , Poliomielite/epidemiologia , Poliomielite/virologia , Poliovirus/genética , Substituição de Aminoácidos , Sequência de Bases , Surtos de Doenças , Fezes/virologia , Genoma Viral , Saúde Global , Guiné/epidemiologia , Doença pelo Vírus Ebola/epidemiologia , Humanos , Hospedeiro Imunocomprometido , Filogenia , Vacina Antipólio Oral , Saúde Pública , Vacinação , Proteínas Virais/genética , Proteínas Virais/metabolismo
7.
Front Cell Infect Microbiol ; 14: 1340096, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-38633747

RESUMO

Introduction: Diffuse large B-cell lymphoma (DLBCL) is an aggressive malignancy of B-cells frequently encountered among people living with HIV. Immunological abnormalities are common in immunocompetent individuals with DLBCL, and are often associated with poorer outcomes. Currently, data on derangements of immunological proteins, such as cytokines and acute phase reactants, and their impact on outcomes in HIV-associated DLBCL (HIV-DLBCL) is lacking. This study assessed the levels and prognostic relevance of interleukin (IL)-6, IL-10 and Transforming Growth Factor Beta (TGFß), the acute phase proteins C-reactive protein (CRP) and ferritin; serum free light chains (SFLC) (elevation of which reflects a prolonged pro-inflammatory state); and the activity of the immunosuppressive enzyme Indoleamine 2,3-dioxygenase (IDO)in South African patients with DLBCL. Methods: Seventy-six patients with incident DLBCL were enrolled, and peripheral blood IL-6, IL-10, TGFß, SFLC and IDO-activity measured in selected patients. Additional clinical and laboratory findings (including ferritin and CRP) were recorded from the hospital records. Results: Sixty-one (80.3%) of the included patients were people living with HIV (median CD4-count = 148 cells/ul), and survival rates were poor (12-month survival rate 30.0%). The majority of the immunological proteins, except for TGFß and ferritin, were significantly higher among the people living with HIV. Elevation of IL-6, SFLC and IDO-activity were not associated with survival in HIV-DLBCL, while raised IL-10, CRP, ferritin and TGFß were. On multivariate analysis, immunological proteins associated with survival independently from the International Prognostic Index (IPI) included TGFß, ferritin and IL-10. Conclusion: Derangements of immunological proteins are common in HIV-DLBCL, and have a differential association with survival compared to that reported elsewhere. Elevation of TGFß, IL-10 and ferritin were associated with survival independently from the IPI. In view of the poor survival rates in this cohort, investigation of the directed targeting of these cytokines would be of interest in our setting.


Assuntos
Infecções por HIV , Linfoma Difuso de Grandes Células B , Humanos , Interleucina-10 , Prognóstico , Interleucina-6 , Proteína C-Reativa , Citocinas , Linfoma Difuso de Grandes Células B/patologia , Ferritinas , Fator de Crescimento Transformador beta , Estudos Retrospectivos
8.
Open Forum Infect Dis ; 11(2): ofad678, 2024 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-38328499

RESUMO

Patients with severe primary immunodeficiency are at risk for complications from live-attenuated vaccines. Here, we report a case of a vaccine-associated paralytic polio and Bacille Calmette-Guérin disease in a 6-month-old girl with severe combined immunodeficiency resulting from homozygous recombinant activating gene 1 deficiency. The patient was successfully treated with intravenous immunoglobulins and oral pocapavir for poliovirus, and antimycobacterial therapy for regional Bacille Calmette-Guérin disease, allowing stem cell transplant. Following transplantation, poliovirus type 3 with 13 mutations was detected from cerebrospinal fluid but not from stool, indicating ongoing viral evolution in the central nervous system despite pocapavir treatment. Clinical improvement and immune reconstitution allowed the patient to be successfully discharged with no further detection of poliovirus.

9.
Nat Commun ; 14(1): 6325, 2023 10 10.
Artigo em Inglês | MEDLINE | ID: mdl-37816740

RESUMO

As global SARS-CoV-2 burden and testing frequency have decreased, wastewater surveillance has emerged as a key tool to support clinical surveillance efforts. The aims of this study were to identify and characterize SARS-CoV-2 variants in wastewater samples collected from urban centers across South Africa. Here we show that wastewater sequencing analyses are temporally concordant with clinical genomic surveillance and reveal the presence of multiple lineages not detected by clinical surveillance. We show that wastewater genomics can support SARS-CoV-2 epidemiological investigations by reliably recovering the prevalence of local circulating variants, even when clinical samples are not available. Further, we find that analysis of mutations observed in wastewater can provide a signal of upcoming lineage transitions. Our study demonstrates the utility of wastewater genomics to monitor evolution and spread of endemic viruses.


Assuntos
COVID-19 , Águas Residuárias , Humanos , SARS-CoV-2/genética , COVID-19/epidemiologia , Vigilância Epidemiológica Baseada em Águas Residuárias , Genômica
10.
Vaccine ; 41 Suppl 1: A35-A47, 2023 04 06.
Artigo em Inglês | MEDLINE | ID: mdl-36907733

RESUMO

Vaccine-derived polioviruses (VDPVs) can emerge from Sabin strain poliovirus serotypes 1, 2, and 3 contained in oral poliovirus vaccine (OPV) after prolonged person-to-person transmission where population vaccination immunity against polioviruses is suboptimal. VDPVs can cause paralysis indistinguishable from wild polioviruses and outbreaks when community circulation ensues. VDPV serotype 2 outbreaks (cVDPV2) have been documented in The Democratic Republic of the Congo (DRC) since 2005. The nine cVDPV2 outbreaks detected during 2005-2012 were geographically-limited and resulted in 73 paralysis cases. No outbreaks were detected during 2013-2016. During January 1, 2017-December 31, 2021, 19 cVDPV2 outbreaks were detected in DRC. Seventeen of the 19 (including two first detected in Angola) resulted in 235 paralysis cases notified in 84 health zones in 18 of DRC's 26 provinces; no notified paralysis cases were associated with the remaining two outbreaks. The DRC-KAS-3 cVDPV2 outbreak that circulated during 2019-2021, and resulted in 101 paralysis cases in 10 provinces, was the largest recorded in DRC during the reporting period in terms of numbers of paralysis cases and geographic expanse. The 15 outbreaks occurring during 2017-early 2021 were successfully controlled with numerous supplemental immunization activities (SIAs) using monovalent OPV Sabin-strain serotype 2 (mOPV2); however, suboptimal mOPV2 vaccination coverage appears to have seeded the cVDPV2 emergences detected during semester 2, 2018 through 2021. Use of the novel OPV serotype 2 (nOPV2), designed to have greater genetic stability than mOPV2, should help DRC's efforts in controlling the more recent cVDPV2 outbreaks with a much lower risk of further seeding VDPV2 emergence. Improving nOPV2 SIA coverage should decrease the number of SIAs needed to interrupt transmission. DRC needs the support of polio eradication and Essential Immunization (EI) partners to accelerate the country's ongoing initiatives for EI strengthening, introduction of a second dose of inactivated poliovirus vaccine (IPV) to increase protection against paralysis, and improving nOPV2 SIA coverage.


Assuntos
Poliomielite , Poliovirus , Humanos , Sorogrupo , República Democrática do Congo/epidemiologia , Poliomielite/epidemiologia , Poliomielite/prevenção & controle , Vacina Antipólio Oral/efeitos adversos , Surtos de Doenças/prevenção & controle
11.
Vaccine ; 41 Suppl 1: A48-A57, 2023 04 06.
Artigo em Inglês | MEDLINE | ID: mdl-36803869

RESUMO

After six years without any detection of poliomyelitis cases, Angola reported a case of circulating vaccine-derived poliovirus type 2 (cVDPV2) with paralysis onset date of 27 March 2019. Ultimately, 141 cVDPV2 polio cases were reported in all 18 provinces in 2019-2020, with particularly large hotspots in the south-central provinces of Luanda, Cuanza Sul, and Huambo. Most cases were reported from August to December 2019, with a peak of 15 cases in October 2019. These cases were classified into five distinct genetic emergences (emergence groups) and have ties with cases identified in 2017-2018 in the Democratic Republic of Congo. From June 2019 to July 2020, the Angola Ministry of Health and partners conducted 30 supplementary immunization activity (SIA) rounds as part of 10 campaign groups, using monovalent OPV type 2 (mOPV2). There were Sabin 2 vaccine strain detections in the environmental (sewage) samples taken after mOPV2 SIAs in each province. Following the initial response, additional cVDPV2 polio cases occurred in other provinces. However, the national surveillance system did not detect any new cVDPV2 polio cases after 9 February 2020. While reporting subpar indicator performance in epidemiological surveillance, the laboratory and environmental data as of May 2021 strongly suggest that Angola successfully interrupted transmission of cVDPV2 early in 2020. Additionally, the COVID-19 pandemic did not allow a formal Outbreak Response Assessment (OBRA). Improving the sensitivity of the surveillance system and the completeness of AFP case investigations will be vital to promptly detect and interrupt viral transmission if a new case or sewage isolate are identified in Angola or central Africa.


Assuntos
COVID-19 , Poliomielite , Poliovirus , Humanos , Esgotos , Angola/epidemiologia , Pandemias , COVID-19/epidemiologia , Poliomielite/prevenção & controle , Vacina Antipólio Oral/efeitos adversos , Surtos de Doenças/prevenção & controle
12.
J Med Microbiol ; 70(10)2021 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-34672918

RESUMO

Introduction. Global poliovirus eradication is a public health emergency of international concern. The acute flaccid paralysis (AFP) surveillance programme in South Africa has been instrumental in eliminating polioviruses and keeping the country poliovirus free.Gap statement. The sensitivity of surveillance for polioviruses by every African country is of global interest in the effort to ensure global health security from poliovirus re-emergence.Aim. To describe the epidemiology of polioviruses from AFP cases and environmental samples in South Africa and to report the performance of the AFP surveillance system for the years 2016-2019 against targets established by the World Health Organization (WHO).Methods. Stool specimens from AFP or suspected AFP cases were received and tested as per WHO guidelines. Environmental samples were gathered from sites across the Gauteng province using the grab collection method. Concentration was effected by the two-phase polyethylene glycol method approved by the WHO. Suspected polioviruses were isolated in RD and/or L20B cell cultures through identification of typical cytopathic effects. The presence of polioviruses was confirmed by intratypic differentiation PCR. All polioviruses were sequenced using the Sanger method, and their VP1 gene analysed for mutations.Results. Data from 4597 samples (2385 cases) were analysed from the years 2016-2019. Two cases of immunodeficiency-associated vaccine-derived poliovirus (iVDPV) type 3 were detected in 2017 and 2018. A further 24 Sabin type 1 or type 3 polioviruses were detected for the 4 years. The national surveillance programme detected an average of 3.1 cases of AFP/100 000 individuals under 15 years old (2.8/100 000-3.5/100 000). The stool adequacy of the samples received was 53.0 % (47.0-55.0%), well below the WHO target of 80 % adequacy. More than 90 % of results were released from the laboratory within the turnaround time (96.6 %) and non-polio enteroviruses were detected in 11.6 % of all samples. Environmental surveillance detected non-polio enterovirus in 87.5 % of sewage samples and Sabin polioviruses in 12.5 % of samples.Conclusion. The AFP surveillance programme in South Africa is sensitive to detect polioviruses in South Africa and provided no evidence of wild poliovirus or VDPV circulation in the country.


Assuntos
Viroses do Sistema Nervoso Central/epidemiologia , Mielite/epidemiologia , Doenças Neuromusculares/epidemiologia , Poliomielite/epidemiologia , Poliovirus/isolamento & purificação , Adolescente , Viroses do Sistema Nervoso Central/prevenção & controle , Viroses do Sistema Nervoso Central/virologia , Criança , Pré-Escolar , Erradicação de Doenças/normas , Erradicação de Doenças/estatística & dados numéricos , Monitoramento Epidemiológico , Fezes/virologia , Humanos , Mielite/prevenção & controle , Mielite/virologia , Doenças Neuromusculares/prevenção & controle , Doenças Neuromusculares/virologia , Poliomielite/prevenção & controle , Poliomielite/virologia , Vacinas contra Poliovirus/isolamento & purificação , Esgotos/virologia , África do Sul/epidemiologia
13.
S Afr J Infect Dis ; 35(1): 196, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-34485481

RESUMO

BACKGROUND: Human enteroviruses (EV) consist of 106 serotypes and four species: EV-A, EV-B, EV-C and EV-D. Enteroviruses cause clinical symptoms varying from severe to mild. Knowledge of EV burden in South Africa is limited, and as non-polio EV are important causes of acute flaccid paralysis (AFP) and meningitis, information on the circulating serotypes is vital. METHODS: Between 2010 and 2012, a total of 832 stool and viral isolate specimens were obtained from two national surveillance programmes at the National Institute for Communicable Diseases: the Rotavirus Sentinel Surveillance Programme (RSSP) and the AFP surveillance programme. Real-time polymerase chain reaction and Sanger sequencing were performed to detect and serotype EV. RESULTS: Non-polio EV were detected in 446 specimens, of which 308 were sequenced. Stool specimens yielded a greater variety of serotypes than viral cultures. EV-B viruses were predominant (58.44%), whilst EV-C viruses were detected in 31% of the specimens tested. South African prevalence for these viruses was higher than other countries, such as France with less than 2%, and Spain and the United States with less than 10%. The most common serotype detected was Enterovirus 99 (EV-C, 8.63%), which has not been reported in other regions. CONCLUSION: Direct sequencing from stool specimens yields a broader, more comprehensive description of EV infections compared to sequencing from viral cultures. Disease-associated serotypes were detected, but only in small numbers. This study provides a baseline for EV strain circulation; however, surveillance needs to be expanded to improve EV knowledge in South Africa.

14.
Pediatr Infect Dis J ; 39(5): 435-437, 2020 05.
Artigo em Inglês | MEDLINE | ID: mdl-32150007

RESUMO

Pocapavir exhibits antiviral activity against both polio and nonpolio enteroviruses. There is limited experience of the use of this investigational drug in young children with enteroviral infection. We describe the successful clearance of prolonged immunodeficiency-associated vaccine-derived type 3 poliovirus infection by pocapavir in an infant with underlying X-linked agammaglobulinemia.


Assuntos
Agamaglobulinemia/complicações , Antivirais/uso terapêutico , Doenças Genéticas Ligadas ao Cromossomo X/complicações , Éteres Fenílicos/uso terapêutico , Poliomielite/tratamento farmacológico , Vacinas contra Poliovirus/efeitos adversos , Poliovirus/efeitos dos fármacos , Drogas em Investigação/uso terapêutico , Fezes/virologia , Humanos , Lactente , Masculino , Poliomielite/diagnóstico , Resultado do Tratamento , Eliminação de Partículas Virais
15.
Int J Prosthodont ; 31(4): 397­398, 2018.
Artigo em Inglês | MEDLINE | ID: mdl-29590666

RESUMO

PURPOSE: To evaluate the effect of premolar axial wall height on the retention of adhesive, full-coverage, computer-aided design/computer-assisted manufacture (CAD/CAM) restorations. MATERIALS AND METHODS: A total of 48 premolar teeth randomized into four groups (n = 12 per group) received all-ceramic CAD/CAM restorations with axial wall heights (AWH) of 3, 2, 1, and 0 mm and 16-degree total occlusal convergence (TOC). Specimens were restored with lithium disilicate material and cemented with self-adhesive resin cement. Specimens were loaded to failure after 24 hours. RESULTS: The 3- and 2-mm AWH specimens demonstrated significantly greater failure load. Failure analysis suggests a 2-mm minimum AWH for premolars with a TOC of 16 degrees. CONCLUSION: Adhesive technology may compensate for compromised AWH.


Assuntos
Dente Pré-Molar/anatomia & histologia , Desenho Assistido por Computador , Coroas , Retenção em Prótese Dentária , Planejamento de Prótese Dentária , Humanos , Técnicas In Vitro , Tamanho do Órgão , Distribuição Aleatória
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