RESUMO
OBJECTIVES: To compare the clinical performance of mildly acidic universal adhesives Scotchbond Universal (SU, 3M Oral Care, St Paul, MN, USA) and Prime & Bond Elect (PBE, Dentsply Sirona, Charlotte, NC, USA) in the restoration of noncarious cervical lesions (NCCLs). METHODS AND MATERIALS: A total of 63 patients in need of 203 NCCL restorations participated in this randomized controlled clinical trial. Notch-shaped lesions were restored with Kalore (GC Corporation, Tokyo, Japan) after application of either SU or PBE, following the etch-and-rinse (ER) or self-etch (SE) techniques. Subjects were followed up for 60 months. The focus of the statistical analyses was on the change of outcome over time as assessed by the Modified USPHS rating system (ie, Alfa vs Bravo + Charlie outcomes). Logistic regression was performed for each outcome separately with compound symmetric variance-covariance structure assumed to consider a correlation of restorations within subjects. All analyses were conducted using SAS 9.4 (SAS, Cary, NC, USA). RESULTS: One-hundred twenty-nine teeth in 35 subjects were assessed at the 60-month follow-up. In addition, three restorations that failed prior to the 60-month evaluation, two of which were in subjects who did not present for the 60-month follow-up, were included in the statistical analysis. In total, two restorations in the SU_ER group and three restorations in the PBE_SE group failed the retention category. Statistically significant differences were obtained for the comparison of restorations in the PBE_SE and PBE_ER groups, where the former was 58% less likely to maintain a score of Alfa for marginal discoloration than the latter. CONCLUSIONS: SU and PBE demonstrated acceptable clinical performance at 60 months with regard to restoration retention. Phosphoric-acid etching of the NCCLs prior to adhesive application significantly improved the performance of PBE in regard to marginal discoloration.
Assuntos
Cimentos Dentários , Adesivos Dentinários , Humanos , Adesivos Dentinários/química , Resinas Compostas/química , Corrosão Dentária/métodos , Restauração Dentária Permanente/métodos , Adaptação Marginal Dentária , Cimentos de Resina/uso terapêutico , Cimentos de Resina/química , Colo do Dente , AdesivosRESUMO
Residual stresses within the veneer are linked to the high prevalence of veneer chipping observed in clinical trials of zirconia prostheses. We hypothesized that the thermal mismatch between the zirconia infrastructure and the veneer porcelain, as well as the rate used for cooling zirconia-veneer crowns, would be directly proportional to the magnitude of residual stresses built within the veneer layer. Two porcelains with different coefficients of thermal expansion were used to veneer zirconia copings, to create high or low thermal mismatches. The crowns were cooled according to a fast- or a slow-cooling protocol. The retardation of polarized light waves was used to calculate the residual stress magnitude and distribution across the veneer, according to the photoelasticity principle, in 1.0-mm-thick crown sections. While thermal mismatch was an important factor influencing the maximum stress development in the veneer, cooling rate had a minor role. Curved surfaces were preferential sites for stress concentration regardless of thermal mismatch or cooling rate.
Assuntos
Coroas , Porcelana Dentária , Facetas Dentárias , Zircônio , Dente Pré-Molar , Birrefringência , Temperatura Baixa , Força Compressiva , Porcelana Dentária/química , Falha de Restauração Dentária , Análise do Estresse Dentário , Elasticidade , Temperatura Alta , Humanos , Teste de Materiais , Fotografia Dentária , Resistência à Tração , Zircônio/químicaRESUMO
UNLABELLED: The functional and esthetic restoration of severely compromised anterior teeth is a challenge to clinicians in their daily practice. The duplication of the optical characteristics of an intact tooth, including shade, translucency, and fluorescence, is often made difficult by the use of metal infrastructures, such as post-and-cores and copings. The development of reinforced ceramics and non-metallic post systems made possible the generation of metal-free ceramic restorations in severely compromised anterior and posterior teeth. This article discusses one available technique for the generation of a single all-ceramic restoration involving the use of a zirconia- or leucite-reinforced post-and-core system and of an all-ceramic crown system. A representative clinical case is presented illustrating the potential of the technique. CLINICAL SIGNIFICANCE: Modern ceramic restorative systems offer the possibility to closely match the natural optical characteristics of lost tooth structure. Posts, cores, and copings fabricated in ceramic materials represent a promising alternative to metals in the restoration of severely compromised anterior teeth.
Assuntos
Coroas , Porcelana Dentária , Técnica para Retentor Intrarradicular , Adulto , Óxido de Alumínio , Silicatos de Alumínio , Materiais Dentários , Feminino , Humanos , Retratamento , ZircônioRESUMO
The purpose of this in vitro study was to evaluate the effect of the length of clinical experience on clinician's diagnosing caries and recommending sealants on the occlusal surfaces of permanent/caries free third molars. The third molars involved in this study had been extracted prior to eruption. There were three study groups: dental students, clinicians with five to ten years experience, and clinicians with fifteen to twenty years of practice. Twenty-four percent of the entire sample diagnosed caries. Clinicians with five to ten years of practice diagnosed occlusal caries significantly more than clinicians with fifteen to twenty years of practice, but not significantly differently than senior dental students. Clinicians recommended sealants significantly more than dental students. The most frequent reason for sealant indication was prevention. The results indicate that clinical experience alone does not impart better caries diagnosis and sealant recommendation criteria.
Assuntos
Competência Clínica , Cárie Dentária/diagnóstico , Selantes de Fossas e Fissuras/uso terapêutico , Atitude do Pessoal de Saúde , Distribuição de Qui-Quadrado , Intervalos de Confiança , Cárie Dentária/prevenção & controle , Odontólogos , Humanos , Dente Serotino/patologia , Variações Dependentes do Observador , Prática Profissional , Estatística como Assunto , Estudantes de Odontologia , Fatores de TempoRESUMO
PURPOSE: To report the 4-year clinical performance of posterior resin-based composite restorations placed using the total-etch technique. MATERIALS AND METHODS: Over a period of 1 year, 726 restorations (248 molars, 478 premolars; 260 Class I, 466 Class II; 540 replacements, 186 primary decay) were placed on conservative preparations, using the incremental placement technique in a clinical environment. Baseline data were collected, and the restorations were evaluated after 4 years. Z100 and Scotchbond Multi-Purpose (SBMP) (3M Dental Products, St. Paul, Minnesota) were used as the restorative system. The criteria evaluated were color match, marginal adaptation, anatomic form, cavosurface marginal discoloration, axial contour, interproximal contact, secondary caries, postoperative sensitivity, and tooth vitality. RESULTS: At baseline, 24% of the teeth restored presented postoperative sensitivity; 86% of the sensitive teeth were from the replacement group. At 4 years, all teeth were vital to cold test. Eighteen restorations (2.5%) presented clinically detectable marginal fracture. The shade was acceptable in all restorations. Cavosurface marginal discoloration was observed in 47 restorations (6.5% bravo scores). Axial contour, interproximal contact, and marginal adaptation received 100% alfa scores. No secondary caries was diagnosed in any of the teeth examined. None of the examined restorations required replacement. CLINICAL SIGNIFICANCE: Under controlled clinical conditions, posterior resin-based composite restorations placed with the total-etch technique and restorative Z100/SBMP have the potential to present a high success rate at 4 years. None of the examined restorations required replacement, and there was no clinically detectable wear in any of the restorations. Simultaneous etching of enamel and dentin followed by the application of a resin adhesive can be considered an adequate modality of pulp protection in nonexposed tooth preparations.
Assuntos
Condicionamento Ácido do Dente/métodos , Resinas Compostas , Restauração Dentária Permanente , Dióxido de Silício , Zircônio , Adolescente , Adulto , Dente Pré-Molar , Cor , Resinas Compostas/química , Cárie Dentária/etiologia , Preparo da Cavidade Dentária , Esmalte Dentário/patologia , Adaptação Marginal Dentária , Polpa Dentária/fisiologia , Restauração Dentária Permanente/classificação , Restauração Dentária Permanente/métodos , Dentina/patologia , Sensibilidade da Dentina/etiologia , Adesivos Dentinários/química , Humanos , Pessoa de Meia-Idade , Dente Molar , Ácidos Fosfóricos/administração & dosagem , Recidiva , Cimentos de Resina/química , Estudos Retrospectivos , Propriedades de Superfície , Resultado do TratamentoRESUMO
STATEMENT OF PROBLEM: Veneer preparations are considered to weaken endodontically treated maxillary incisors. Prefabricated posts have been controversially indicated to reinforce endodontically treated teeth before final restoration. PURPOSE: This in vitro study evaluated whether (1) veneer preparation in enamel or in enamel/dentin weakens endodontically treated maxillary incisors, (2) bonding of direct composite veneer restores the original strength of the unprepared teeth, and (3) use of prefabricated metal posts increases fracture resistance of prepared and restored teeth. MATERIAL AND METHODS: Ninety extracted human maxillary central incisors were submitted to conventional root canal treatment. Specimens were randomly divided into 8 experimental groups (veneer preparation in enamel or dentin with/without post and with/without direct composite veneer restoration) and a control group (n = 10). Specimens were loaded to fracture, and the data were analyzed statistically. RESULTS: Statistical analysis revealed that a conservative veneer preparation does not significantly reduce maxillary incisors' fracture resistance. For prepared incisors, bonding of direct composite veneer restored their original strength, and the use of posts did not increase their fracture resistance. CONCLUSION: Conservative veneer preparations involving enamel and enamel/dentin did not significantly reduce the fracture resistance of endodontically treated maxillary incisors. In addition, restoration of the intraenamel preparations with direct composite resulted in teeth more resistant to fracture than teeth having restorations in dentin. The use of posts did not improve fracture resistance of endodontically treated maxillary incisors reduced and veneered with direct composite.
Assuntos
Facetas Dentárias , Técnica para Retentor Intrarradicular , Fraturas dos Dentes/prevenção & controle , Dente não Vital , Análise de Variância , Resinas Compostas , Análise do Estresse Dentário , Facetas Dentárias/efeitos adversos , Humanos , Incisivo/lesões , Maxila , Estatísticas não Paramétricas , Fraturas dos Dentes/etiologiaRESUMO
A technique for manufacturing direct resin composite veneers is presented. Described are the advantages of using an acrylic resin matrix, made before the preparation is begun, to copy anatomic details. An additional step to mask previously prepared dark enamel with opaquers is also described. The advantages and limitations of the procedures are discussed.
Assuntos
Facetas Dentárias , Descoloração de Dente/terapia , Resinas Compostas , HumanosRESUMO
UNLABELLED: Metal-free ceramic restorations are increasingly popular for restoring posterior teeth. These restorations are generated through a variety of techniques (e.g., CAD-CAM, copy-milling, heat-pressing, and firing). When appropriately indicated and made, ceramic inlays or onlays can be reliable and provide a highly serviceable restoration. The aim of this article is to review and present updated information regarding indications, restorative technique, and maintenance for this class of restorations, with emphasis to fired ceramic inlays or onlays. The information presented is based on 15 years of controlled clinical experience with this category of restorations. Clinical cases that represent some applications also are presented. CLINICAL SIGNIFICANCE: The fired ceramic inlay/onlay technique is presented as a viable option for the esthetic and adhesive restoration of posterior teeth.
Assuntos
Porcelana Dentária , Restaurações Intracoronárias , Dente Pré-Molar , Colagem Dentária , Preparo da Cavidade Dentária , Técnica de Moldagem Odontológica , Planejamento de Prótese Dentária , Restauração Dentária Temporária , Humanos , Dente Molar , Ajuste Oclusal , Seleção de Pacientes , Preparo Prostodôntico do DenteRESUMO
OBJECTIVE: The purpose of this project was to evaluate the performance of a dentin adhesive system on carious and noncarious primary dentin in vivo. METHOD AND MATERIALS: Forty-eight primary molars with carious lesions were randomly assigned to 2 different treatments: group 1 (control, n = 24)--All identifiable, irreversibly infected dentin was removed prior to the application of the bonding agent and restorative material; group 2 (experimental, n = 24)--Irreversibly infected dentin was partially removed prior to the application of the bonding agent and restorative material. The control and experimental teeth were clinically monitored every 3 months and evaluated 12 months after restoration. The teeth were extracted around the time of exfoliation and processed for scanning electron microscopy. RESULTS: Retention rate, marginal integrity, and pulpal symptoms were identical in both groups. Radiographically, the radiolucent area associated with the experimental restorations did not increase with time in 75% of the cases. For the control group, the adhesive system formed a hybrid layer. In the experimental group, there was morphologic evidence of the formation of an acid-resistant "altered hybrid layer." An acid-resistant tissue, resulting from the interdiffusion of adhesive resin within the area of carious dentin, was observed adjacent to and under the altered hybrid layer. CONCLUSION: Application of an adhesive restorative system to irreversibly infected dentin did not affect the clinical performance of the restoration.