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1.
J Endod ; 40(8): 1201-5, 2014 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-25069933

RESUMO

INTRODUCTION: Luting posts inside the root canal is still a challenge because of the difficulty of bonding adhesive materials in the apical third of roots. This study evaluated the effect of the application mode of 3 simplified etch-and-rinse adhesives on the push-out bond strength (PBS), nanoleakage (NL), and in situ degree of conversion (DC) of fiber posts in the root canal. METHODS: The roots of human premolars were endodontically prepared and divided into 6 groups according to the combination of the main factors: adhesive (Ambar, FGM, Joinville, SC, Brazil; Adper Single Bond 2, 3MESPE, St Paul, MN; and XP Bond+self-cure activator, DeTrey Dentsply, Konstanz, Germany) and application mode (manual or sonic). The posts were cemented and the PBS tested at 0.5 mm/min. The NL was evaluated by scanning electron microscopy after the immersion of specimens in 50% silver nitrate. Micro-Raman spectroscopy was used to measure the in situ DC. Root third was also considered in the statistical evaluation. Data were analyzed by 3-way repeated measures analysis of variance and Tukey tests (5%). RESULTS: Under sonic application, the PBS and the in situ DC increased, whereas NL decreased significantly for all groups in the middle and apical thirds (P < .05). CONCLUSIONS: The application of simplified adhesives by sonic mode in the root canal is a feasible tool to increase the fiber post bond to root canals.


Assuntos
Colagem Dentária/métodos , Cavidade Pulpar/ultraestrutura , Adesivos Dentinários/química , Técnica para Retentor Intrarradicular/instrumentação , Cimentos de Resina/química , Sonicação/métodos , Bis-Fenol A-Glicidil Metacrilato/química , Cimentação/métodos , Cimentos Dentários/química , Infiltração Dentária/classificação , Análise do Estresse Dentário/instrumentação , Humanos , Teste de Materiais , Metacrilatos/química , Microscopia Eletrônica de Varredura , Polietilenoglicóis/química , Polimerização , Ácidos Polimetacrílicos/química , Distribuição Aleatória , Preparo de Canal Radicular/métodos , Coloração pela Prata/métodos , Análise Espectral Raman , Estresse Mecânico , Ápice Dentário/ultraestrutura , Dente não Vital/patologia
2.
J Dent ; 36(4): 249-55, 2008 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-18308450

RESUMO

OBJECTIVES: The aim of this study was to compare the fracture strength of three techniques used to re-attach tooth fragments in sound and endodontically treated fractured teeth with or without fiber post placement. MATERIAL AND METHODS: Ninety human lower incisors were randomly divided into three groups of 30 teeth each. In group A teeth were not subjected to endodontic treatment; while teeth from groups B and C were endodontically treated and the pulp chamber restored with a composite resin. All teeth were fractured by an axial load applied to the buccal area in order to obtain tooth fragments. Teeth from each group were then divided into three subgroups, according to the re-attachment technique: bonded-only, buccal-chamfer and circumferential chamfer. Before the re-attachment procedures, fiber posts were placed in teeth from group C using dual cure resin luting cement (Duo-Link). All teeth (groups A-C) had the fragments re-attached using a same dual cure resin luting cement. In the bonded-only group, no additional preparation was made. After re-attachment of the fragment, teeth from groups buccal and circumferential chamfer groups had a 1.0 mm depth chamfer placed in the fracture line either on buccal surface or along the buccal and lingual surfaces, respectively. Increments of microhybid composite resin (Tetric Ceram) were used in subgroups buccal chamfer and circumferential chamfer to restore the chamfer. The specimens were loaded until fracture in the same pre-determined area. The force required to detach each fragment was recorded and the data was subjected to a three-way analysis of variance where factors Group and Re-attachment technique are independent measures and Time of fracture is a repeated measure factor (first and second) and Tukey's test (alpha=0.05). RESULTS: The main factors Re-attachment technique (p=0.04) and Time of fracture (p=0.02) were statistically significant. The buccal and circumferential chamfer techniques were statistically similar (p>0.05) and superior to the bonded-only group (p<0.05). The first time of fracture was statistically superior to second time of fracture (p<0.001). CONCLUSIONS: The use of fiber post is not necessary for the reinforcement of the tooth structure in re-attachment of endodontically treated teeth. When bonding a fractured fragment, the buccal or circumferential re-attachment techniques should be preferable in comparison with the simple re-attachment without any additional preparation. None of the techniques used for re-attachment restored the fracture strength of the intact teeth.


Assuntos
Colagem Dentária/métodos , Restauração Dentária Permanente/métodos , Técnica para Retentor Intrarradicular , Coroa do Dente/lesões , Fraturas dos Dentes/terapia , Resinas Compostas , Análise do Estresse Dentário , Humanos , Cimentos de Resina , Dente não Vital
3.
Oper Dent ; 33(1): 79-88, 2008.
Artigo em Inglês | MEDLINE | ID: mdl-18335737

RESUMO

This study examined the early and long-term microtensile bond strengths (MTBS) and interfacial enamel gap formation (IGW) of two-step self-etch systems to unground and ground enamel. Resin composite (Filtek Z250) buildups were bonded to proximal enamel surfaces (unground, bur-cut or SiC-treated enamel) of third molars after the application of four self-etch adhesives: a mild (Clearfil SE Bond [SE]), two moderate (Optibond Solo Plus Self-Etch Primer [SO] and AdheSE [AD]) and a strong adhesive (Tyrian Self Priming Etchant + One Step Plus [TY]) and two etch-and-rinse adhesive systems (Single Bond [SB] and Scotchbond Multi-Purpose Plus [SBMP]). Ten tooth halves were assigned for each adhesive. After storage in water (24 hours/37 degrees C), the bonded specimens were sectioned into beams (0.9 mm2) and subjected to microTBS (0.5 mm/minute) or interfacial gap width measurement (stereomicroscope at 400x) either immediately (IM) or after 12 months (12M) of water storage. The data were analyzed by three-way repeated measures ANOVA and Tukey's test (alpha=0.05). No gap formation was observed in any experimental condition. The microTBS in the Si-C paper and diamond bur groups were similar and greater than the unground group only for the moderate self-etch systems (SO and AD). No reductions in bond strength values were observed after 12 months of water storage, regardless of the adhesive evaluated.


Assuntos
Condicionamento Ácido do Dente/métodos , Colagem Dentária , Adaptação Marginal Dentária , Cimentos de Resina , Análise de Variância , Esmalte Dentário , Análise do Estresse Dentário , Armazenamento de Medicamentos , Humanos , Dente Molar , Estatísticas não Paramétricas , Propriedades de Superfície , Resistência à Tração , Água
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