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1.
J Adhes Dent ; 22(1): 35-45, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-32030374

RESUMO

PURPOSE: The aim of this review article was to provide an overview of the scientific and patent literature on the different synthesis pathways of modified polyacids suitable for application in a new class of restorative dental materials. METHODS: The literature based on patents and publications from 2009 to 2018 of Dentsply Sirona in cooperation with Heinrich Heine University, Düsseldorf, was reviewed and summarized. RESULTS: Multiple approaches towards the development of polymerizable acid polymers have been introduced and their strength and weaknesses were discussed. A target structure and the respective synthesis were developed allowing the formulation of a restorative dental material with unique properties, such as high mechanical strength paired with good adhesion properties. CONCLUSION: From a variety of hydrolytically stable acidic polymers, the most promising versions were selected and used for the product development of Surefil one (Dentsply Sirona).


Assuntos
Materiais Dentários , Polímeros , Resinas Compostas , Teste de Materiais , Propriedades de Superfície
2.
J Adhes Dent ; 22(1): 47-58, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-32030375

RESUMO

PURPOSE: The development of a novel material requires a comprehensive pre-clinical assessment of clinical longevity before any market release. This study aimed to investigate the mechanical performance of a novel self-adhesive restorative material (ASAR MP4). MATERIALS AND METHODS: Fracture strength (FS), flexural fatigue strength (FFS) and fracture toughness (KIc) were measured for the experimental material ASAR MP4 in self-cure (SC) and light-cure (LC) mode. ASAR MP4 was processed in capsules. Three direct resin composites (CeramX mono+, DentsplySirona; Heliomolar, IvoclarVivadent; Filtek Supreme XTE, 3M) and two glass-ionomer-cement (GIC) based materials (Equia Forte, GC; Fuji II LC, GC) were selected for comparison with ASAR MP4. FS specimens (n = 15) were tested in a 4-point bending configuration according to ISO 4049 and 9917. FFS specimens (n = 25) were additionally stressed for 104 loading cycles using the staircase approach. The single-edge-notch beam (SENB) configuration was selected for determining KIc according to ISO 13586. All specimens were stored for 14 days at 37°C. Data were analyzed using Weibull statistics (FS), ANOVA (FS, KIc), and the non-parametric Mann-Whitney U-test (FFS). RESULTS: The FS, FFS and KIc data of the ASAR MP4 material reveal a mechanical performance in the range of the successful permanent direct resin composites CeramX mono+ and Heliomolar. The results for ASAR MP4 in SC mode were superior to the LC mode. A fine-grained and pore-free microstructure was observed. CONCLUSION: Within the limitations of this study we conclude that the novel self-adhesive restorative material ASAR MP4 exhibits mechanical performance close to that of the resin composites Heliomolar and CeramX mono+, both indicated for permanent use in the load-bearing posterior region. Processing the material in either self-cure or light-cure mode led to superior performance over glass-ionomer cements.


Assuntos
Resinas Compostas , Cimentos Dentários , Materiais Dentários , Cimentos de Ionômeros de Vidro , Teste de Materiais , Cimentos de Resina
3.
J Adhes Dent ; 22(1): 59-64, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-32030376

RESUMO

PURPOSE: To investigate simulated localized and generalized wear of self-adhesive restorative materials. MATERIALS AND METHODS: Three commercially available restorative materials and one experimental material with self-adhesive properties were evaluated. The experimental material was tested in both light-cured and self-cured conditions. Activa (A), Fuji II LC (F), and Equia Forte (E) and the experimental material ASAR-MP4 (S) were investigated. Two kinds of wear were simulated in an Alabama wear machine. Localized wear was simulated with a stainless-steel ball bearing antagonist and generalized with a flat-ended stainless-steel cylinder antagonist. The wear challenge was carried out in an aqueous slurry of polymethyl methacrylate beads. Material volume loss was measured on polyvinyl siloxane replicates of each worn surface using a Proscan 2100 noncontact profilometer in conjunction with Proscan and AnSur 3D software. RESULTS: There were significant differences (p < 0.05) among the materials for both generalized and localized wear. The experimental material in both curing modes exhibited significantly less localized wear than F and A and significantly less generalized wear than F and E. CONCLUSION: Self-adhesive materials offer unique handling properties for direct placement of posterior restorations in permanent teeth. The experimental material ASAR-MP4 generated similar wear values to the other self-adhesive materials tested.


Assuntos
Resinas Compostas , Desgaste de Restauração Dentária , Cimentos Dentários , Materiais Dentários , Cimentos de Ionômeros de Vidro , Teste de Materiais , Propriedades de Superfície
4.
J Adhes Dent ; 22(1): 65-77, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-32030377

RESUMO

PURPOSE: This study investigated the bonding efficacy of a new so-called self-adhesive composite hybrid onto flat (FLAT) and high C-factor class-I cavity-bottom (CAVITY) dentin. MATERIALS AND METHODS: The immediate and aged (50,000 thermocycles) microtensile bond strength (µTBS) to FLAT and CAVITY dentin of the experimental self-adhesive bulk-fill restorative (K-0180 ASAR pilot [ASAR-pilot], Dentsply Sirona) was compared to that of two universal adhesives applied in self-etch mode and combined with a bulk-fill composite (Prime&Bond Elect/QuiXfil [P&Be/QuiXF], Prime&Bond Active/QuiXfil [P&Ba/QuiXF], both Dentsply Sirona), two pre-conditioned materials (Activa Bioactive-Restorative [Activa], Pulpdent; Fuji II LC Improved [Fuji2LC], GC); and one bulk-fill glass-hybrid restorative (Equia Forte Fil [EquiaF], GC). Statistically significant differences were recorded using Welch's ANOVA with Games-Howell contrast (p < 0.05). RESULTS: No significant difference in immediate µTBS was recorded when the restorative materials were applied onto FLAT dentin, except for Activa_FLAT and EquiaF_FLAT. When bonded to CAVITY dentin, the significantly highest µTBS was recorded for Fuji2LC_CAVITY (layer filled), and was not significantly different only from P&Ba/QuiXF_CAVITY. Upon aging, the highest µTBS to flat dentin was achieved by ASAR-pilot_FLAT, which was not significantly different from P&Be/QuiXF_FLAT and Fuji2LC_FLAT. No significant difference between immediate and aged µTBS was recorded for ASAR-pilot when bonded onto FLAT or CAVITY dentin; the latter, however, was associated with low bond strength. CONCLUSION: Favorable bonding performance was found for the new self-adhesive bulk-fill composite hybrid ASAR-pilot when bonded to flat dentin. However, much lower bond strength was recorded when ASAR-pilot was bonded to high C-factor cavity-bottom dentin.


Assuntos
Colagem Dentária , Adesivos Dentinários , Resinas Compostas , Cimentos Dentários , Dentina , Teste de Materiais , Cimentos de Resina , Resistência à Tração
5.
J Adhes Dent ; 22(1): 85-97, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-32030379

RESUMO

PURPOSE: The material structure and chemical elemental composition of a new self-adhesive composite hybrid were investigated. The bonding performance when applied on flat (FLAT) vs high C-factor class-I cavity-bottom (CAVITY) dentin and in light-cure (LC) vs self-cure (SC) mode was determined. MATERIALS AND METHODS: The self-adhesive bulk-fill composite Surefil One (Su-O; Dentsply Sirona) was compared with the resin-modified glass-ionomer Fuji II LC Improved (Fuji2LC; GC) and the ion-releasing alkasite material Cention N (CentionN; Ivoclar Vivadent). The material structure was examined with SEM and TEM, while the chemical elemental composition was analyzed using EDS. The immediate and aged microtensile bond strength (µTBS) of Su-O_LC/SC was compared to that of Fuji2LC applied without any pre-treatment, and to that of CentionN applied following bonding with Adhese Universal (AU) (Ivoclar Vivadent) in self-etch mode (AU/CentionN). All restorative materials were bonded onto FLAT and CAVITY dentin. Statistical analysis was performed with the Kruskal-Wallis nonparametric test. RESULTS: EDS analysis revealed that Su-O was richer in C and P than the reference restorative materials. Applied to FLAT dentin, the significantly highest immediate and aged µTBS were recorded for AU/CentionN, which were not significantly different only from Su-O_LC. Applied to CAVITY dentin, the significantly highest immediate µTBS was recorded for AU/CentionN, which did not differ significantly only from Su-O_SC. Su-O_LC bonded to CAVITY dentin suffered from a high incidence of pre-test failures. CONCLUSION: While Su-O_LC bonded effectively and durably to FLAT dentin, Su-O_SC bonded more favorably than Su-O_LC in class-I cavities, which was probably related to shrinkage stress variously challenging the respective bond.


Assuntos
Colagem Dentária , Adesivos Dentinários , Resinas Compostas , Cimentos Dentários , Dentina , Teste de Materiais , Cimentos de Resina , Resistência à Tração
6.
J Adhes Dent ; 22(1): 107-116, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-32030381

RESUMO

PURPOSE: This in vitro study evaluated marginal integrity, 2-body wear, and fracture behavior of an array of bonded and nonbonded posterior restorative materials after thermomechanical loading (TML). MATERIALS AND METHODS: Eighty-eight MOD cavities with one proximal box beneath the CEJ were prepared in extracted human third molars according to a well-established protocol. Direct restorations were made using the following materials: amalgam (Dispersalloy), Ketac Molar Quick, Surefil One (with or without light curing), Activa, AdheSE Universal/Heliomolar, Fuji II LC improved, Equia Forte, Scotchbond Universal/Filtek Supreme, Xeno V+/CeramX.mono+, Prime&Bond active/Spectra ST CeramX HV, Prime&Bond elect/Spectra ST CeramX HV. Before and after thermomechanical loading (2500/5000/12,500 thermocycles between 5°C and 55°C + 100,000/ 200,000/500,000 x 50 N), marginal gaps and 2-body wear depths were analyzed on epoxy resin replicas using SEM and CLSM. Fractures were observed under a light microscope (20X). Results were analyzed with Kruskal-Wallis and Mann-Whitney U-tests (p < 0.05). RESULTS: For marginal quality, Surefil One showed promising in vitro behavior close to that of resin composite bonded with a self-etch adhesive (p > 0.05). For wear, amalgam and resin composites with recent filler technology were still superior (p < 0.05), but Surefil One LC outperformed Activa, Ketac Molar Quick, Equia Forte Fil, and Fuji II LC (p < 0.05). When Surefil One was occlusally light cured, no fractures occured, even after 500,000 cycles of TML. CONCLUSION: The novel self-adhesive posterior restorative Surefil One did not exhibit superior outcomes for all evaluated aspects. However, it showed stable fracture behavior, good marginal quality, and acceptable wear resistance in vitro.


Assuntos
Adaptação Marginal Dentária , Restauração Dentária Permanente , Resinas Compostas , Materiais Dentários , Cimentos de Ionômeros de Vidro , Humanos , Teste de Materiais , Cimentos de Resina
7.
Artigo em Inglês | MEDLINE | ID: mdl-32032415

RESUMO

This article reports a comprehensive restorative treatment using bulk-fill composites and discusses their properties and clinical performance. A 20-year-old man sought dental treatment due to the dark shade of his smile and multiple old amalgam fillings. Based on clinical and radiographic findings, and the patient's demand for tooth-colored fillings, treatment comprised enamel microabrasion and in-office dental bleaching, followed by the replacement of amalgam fillings by bulk-fill composites. Bulk-fill composites exhibit modifications in the filler size and shape or in the chemistry of monomers that allow them to be applied in thicker layers (4 to 5 mm), creating opportunities for simpler, faster, and more-efficient clinical procedures, as seen in the present report.


Assuntos
Resinas Compostas , Dente , Adulto , Materiais Dentários , Humanos , Teste de Materiais , Adulto Jovem
8.
Oral Health Prev Dent ; 18(1): 71-76, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-32051973

RESUMO

PURPOSE: The aim of this in vitro study was to evaluate the influence of preapplication of 2% chlorhexidine gluconate on the immediate microtensile bond strength of a universal adhesive system on dentine subjected to different bonding protocols. MATERIALS AND METHODS: Twenty human molars were used in this study, and the tooth surface was abraded to expose the dentine. The teeth were randomly divided into four groups according to the surface treatment (n = 5): SBU group: Single Bond Universal without acid etching; SBUPA group: 37% phosphoric acid + Single Bond Universal; SBUCG group: 2% chlorhexidine gluconate + Single Bond Universal; and SBUPACG group: 37% phosphoric acid + 2% chlorhexidine gluconate + Single Bond Universal. The microtensile bond strengths were measured using a microtensile tester 24 h after bonding. The bond strength data were subjected to analysis of variance (ANOVA) and Sheffé's least statistically significant difference test (α = 0.05). RESULTS: No statistically significant differences between the analysed groups were observed (p > 0.05). However, conditioning with phosphoric acid without the action of the chlorhexidine gluconate group resulted in higher numerical values of bond strengths than that for the chlorhexidine gluconate without the acid conditioning group. CONCLUSION: The preapplication of 2% chlorhexidine gluconate did not reduce the immediate bond strength of the Single Bond Universal adhesive system under different bonding protocols.


Assuntos
Colagem Dentária , Adesivos Dentinários , Ataque Ácido Dentário , Clorexidina/análogos & derivados , Resinas Compostas , Cimentos Dentários , Dentina , Humanos , Teste de Materiais , Projetos Piloto , Propriedades de Superfície , Resistência à Tração
10.
Braz Oral Res ; 34: e001, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-32022221

RESUMO

This study analyzed the effect of prior application of copaiba oil (CO) emulsions as a dentin cleaning substance on microleakage and microtensile adhesive strength. Twenty-five premolars and sixty-four molars were used for microleakage and microtensile assays. For the microleakage assays, specimens with standard class V cavities were divided (n = 5), according to the tested CO emulsions: CO10%X, CO10%Y, and CO10%Z, as well as chlorhexidine 2% (CHX) and distilled water (DW), as positive and negative controls, respectively. Restorations were performed using the Adper Single Bond® and/or Clearfil SE Bond® systems. Cervical, occlusal, distal and mesial sections were assessed for tracer penetration degree at the composite/tooth interface. For the microtensile assay, healthy molars were divided into sixteen groups, in which artificial caries were induced in half of the groups. Dentin surfaces were treated with CO10%X and CO10%Y, CHX and DW. Microtensile bond strength was measured by fixing each sample to the plate of a universal testing machine operated at a speed of 0.5 mm/minute until failure. Dentin treated with CO10%X showed a lower infiltration rate than dentin treated with the other CO emulsions, CHX2% and DW. According to the microtensile assay, both healthy and affected dentin treated with CO10%X and Adper Single Bond® adhesive system presented higher adhesive strength. CO emulsion, used as a dentin biomodifier, interfered positively in microleakage and improved adhesive strength after acid etching in the Adper Single Bond® adhesive system, or before applying the Clearfil SE Bond® self-etching system.


Assuntos
Colagem Dentária/métodos , Adesivos Dentinários/química , Dentina/efeitos dos fármacos , Fabaceae/química , Óleos Vegetais/química , Análise de Variância , Clorexidina/química , Resinas Compostas/química , Cimentos Dentários/química , Infiltração Dentária , Dentina/química , Emulsões/química , Humanos , Teste de Materiais , Reprodutibilidade dos Testes , Cimentos de Resina/química , Estatísticas não Paramétricas , Propriedades de Superfície , Resistência à Tração
11.
Braz Oral Res ; 34: e005, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-32022224

RESUMO

The purpose of this study was to evaluate the effect of ionizing radiation from high energy X-ray on fluoride release, surface roughness, flexural strength, and surface chemical composition of the materials. The study groups comprised five different restorative materials: Beautifil II, GCP Glass Fill, Amalgomer CR, Zirconomer, and Fuji IX GP. Twenty disk-shaped specimens (8x2 mm) for fluoride release and 20 bar-shaped specimens (25 x 2x 2 mm) for flexural strength were prepared from each material. Each material group was divided into two subgroups: irradiated (IR) and non-irradiated (Non-IR). The specimens from IR groups were irradiated with 1.8 Gy/day for 39 days (total IR = 70.2 Gy). The amount of fluoride released into deionized water was measured using a fluoride ion-selective electrode and ion analyzer after 24 hours and on days 2, 3, 7, 15, 21, 28, 35, and 39 (n = 10). The flexural strength was evaluated using the three-point bending test (n = 10). After the period of measurement of fluoride release, seven specimens (n = 7) from each group were randomly selected to evaluate surface roughness using AFM and one specimen was randomly selected for the SEM and EDS analyses. Data were analyzed with two-way ANOVA and Tukey tests (p = 0.05). The irradiation significantly increased fluoride release and surface roughness for Amalgomer CR and Zirconomer groups (p < 0.05). No significant change in flexural strength of the materials was observed after irradiation (p > 0.05). The ionizing radiation altered the amount of fluoride release and surface roughness of only Amalgomer CR and Zirconomer. The effect could be related to the chemical compositions of materials.


Assuntos
Apatitas/efeitos da radiação , Bis-Fenol A-Glicidil Metacrilato/efeitos da radiação , Resinas Compostas/efeitos da radiação , Fluoretos/química , Cimentos de Ionômeros de Vidro/efeitos da radiação , Radiação Ionizante , Zircônio/efeitos da radiação , Análise de Variância , Apatitas/química , Bis-Fenol A-Glicidil Metacrilato/química , Resinas Compostas/química , Resistência à Flexão , Cimentos de Ionômeros de Vidro/química , Teste de Materiais , Microscopia Eletrônica de Varredura , Valores de Referência , Reprodutibilidade dos Testes , Espectrometria por Raios X , Estatísticas não Paramétricas , Propriedades de Superfície/efeitos da radiação , Fatores de Tempo , Zircônio/química
12.
Am J Dent ; 33(1): 39-42, 2020 02.
Artigo em Inglês | MEDLINE | ID: mdl-32056414

RESUMO

PURPOSE: This randomized, controlled study evaluated the 2-year clinical performance of two flowable resin composites performed with a universal adhesive in two etching modes for restoring non-carious cervical lesions (NCCLs). METHODS: One hundred NCCLs were restored with two flowable composites ( Charisma Opal Flow and G-aenial Universal Flo) and a universal adhesive (Single Bond Universal) with two etching modes (self-etch and etch&rinse) in a random order. The restorations were evaluated for retention, marginal adaptation, anatomic form, marginal discoloration, surface texture and secondary caries (modified USPHS criteria) at baseline, and after 6, 12 and 24 months. RESULTS: The clinical success for retention, surface texture and secondary caries parameters was scored as 100% for each group after 6, 12 and 24 months. The first acceptable changes (Bravo score) in marginal adaptation, anatomical form and marginal discoloration started to show up after 12 months for all test groups, except for etch&rinse+Charisma Opal Flow. Self-etch+Charisma Opal Flow and self-etch+G-aenial Universal Flo showed progressive marginal discoloration that remained in the clinical acceptability level after 2 years. After 24 months, each resin composite restored with either the etch&rinse mode or the self-etch mode of the universal adhesive showed similar clinical performance. Marginal discoloration was higher in the restorations performed with the self-etch system. Selective-etching can be favorable. CLINICAL SIGNIFICANCE: The clinical performance of flowable composites performed with a universal adhesive in two etching modes was clinically acceptable after 24 months.


Assuntos
Cárie Dentária , Restauração Dentária Permanente , Resinas Compostas , Cimentos Dentários , Adaptação Marginal Dentária , Seguimentos , Humanos , Cimentos de Resina , Colo do Dente
13.
Pediatr Dent ; 42(1): 47-52, 2020 Jan 15.
Artigo em Inglês | MEDLINE | ID: mdl-32075711

RESUMO

Purpose: Erosive tooth wear often leads to surface loss requiring restoration of primary teeth with adhesive materials. The purpose of this study was to evaluate the microshear bond strength (µSBS) of different adhesive systems to sound and eroded primary enamel and dentin surfaces. Methods: Half of the samples underwent erosion (immersion in Coca-Cola for one minute five times over five days) and abrasion cycles (brushing with an electric toothbrush, fluoride toothpaste slurry, for one minute at 250 g load). Samples were divided into adhesive groups (n equals 12): Adper Single Bond 2 (etch-and-rinse); Single Bond Universal (self-etch); Optibond FL (etch-and-rinse with fluoride); and Bond-Force (self-etch with fluoride). Resin composite was bonded on sample surfaces and subjected to µSBS test. Data were analyzed by two-way analysis of variance, Tukey test, and chi-square test (P<0.05). The failure mode was determined using a stereomicroscope under 20X magnification. Results: No difference was found between the eroded and sound enamel and dentin (P≥ 0.05) on µSBS test. The failure mode evaluation showed significant differences between sound and eroded dentin (P=0.003) but no difference among the adhesives (P=0.177). Conclusions: Micro-shear bond strength in primary enamel and dentin was not affected by erosion/abrasion or type of adhesive system.


Assuntos
Colagem Dentária , Resinas Compostas , Esmalte Dentário , Dentina , Adesivos Dentinários , Teste de Materiais , Cimentos de Resina , Resistência ao Cisalhamento
14.
Quintessence Int ; 51(2): 108-115, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-31942572

RESUMO

OBJECTIVES: This laboratory study compared the effects of various post systems on the fracture resistance of endodontically treated mandibular premolars. METHOD AND MATERIALS: Thirty-two extracted mandibular first premolars were collected, endodontically treated, and assigned into four test groups (n = 8). The classification was based on the post material as follows: traditional glass-fiber posts (TFP), traditional titanium posts (TTP), coated glass-fiber posts (CFP), and coated titanium posts (CTP). The posts were cemented with a dual-curing luting composite resin. Each specimen, which was prepared with a 2-mm ferrule height, received a composite resin core. All specimens were restored with cast CoCr crowns, which were cemented with glass-ionomer cement. All specimens were submitted to dynamic loading in a dual-axis chewing simulator for 1,200,000 cycles with a nominal load of 5 kg and simultaneous thermal cycling (5 to 55°C). Each specimen was secured in place and loaded at 30 degrees using a universal testing machine until fracture occurred. The results obtained were analyzed using one-way ANOVA and the fracture modes were investigated under stereomagnification (25×). RESULTS: Fracture loads were as follows: 858 ± 216 N for CTP, 953 ±134 N for TFP, 979 ± 219 N for CFP, and 1,130 ± 286 N for TTP group. One-way ANOVA revealed no statistically significant differences among the test groups (P = .112). CONCLUSIONS: Under the conditions of the current study, no significant fracture resistance differences were found between teeth with the different prefabricated post systems.


Assuntos
Técnica para Retentor Intrarradicular , Fraturas dos Dentes , Dente não Vital , Resinas Compostas , Coroas , Falha de Restauração Dentária , Análise do Estresse Dentário , Humanos
15.
Int J Esthet Dent ; 15(1): 108-117, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-31994539

RESUMO

Post and core fabrication is important in the restoration of endodontically treated teeth. Significant coronal and radicular dentin destruction commonly occurs in endodontically treated teeth. As a result, preserving all the remaining tooth structure is imperative in order to improve the prognosis of the restorative treatment. Core height and width need to be carefully designed and built in order to receive the final restoration. Direct free-hand composite resin core buildup in increments may be a challenging and time-consuming procedure in the dental chair. The case report presented in this article describes a clinical technique using a clear matrix to receive composite resin injections in order to achieve an ideal shape and core size.


Assuntos
Técnica para Retentor Intrarradicular , Fraturas dos Dentes , Dente não Vital , Resinas Compostas , Dentina , Humanos
16.
J Clin Pediatr Dent ; 44(1): 41-46, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-31995416

RESUMO

OBJECTIVE: To evaluate penetration of a flowable resin composite into fissures using three different application methods: (1) conventional, (2) heat, and (3) sonic vibration. STUDY DESIGN: Forty-five sound maxillary third molars were divided randomly into three groups (n=15 per group). The occlusal surfaces of the teeth were etched and flowable resin composites were applied into the fissure using the assigned application method. The crowns were sectioned and examined with an optical microscope to assess penetration. In addition, three-point flexural strength was analyzed. RESULTS: The sonic vibration group exhibited significantly greater penetration into the fissure compared with the other test groups (p<0.001). The heat group exhibited greater penetration into the fissure compared with the conventional group (p=0.003). However, three-point flexural strength was similar among all groups (p>0.05). CONCLUSIONS: Sonic vibration and heat increased penetration into fissures. Notably, sonic vibration exhibited the greatest penetration. We found that the application method did not influence the three-point flexural strength.


Assuntos
Temperatura Alta , Selantes de Fossas e Fissuras , Resinas Compostas , Dente Molar , Vibração
17.
Braz Oral Res ; 33: e121, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-31939500

RESUMO

The objective of the study was to analyze the surface area (SA) of the wear caused by simulated chewing on human enamel and opposing restorative material, namely: composite resin (CR), porcelain fused to metal (PFM), lithium disilicate (LD), or monolithic zirconia (MZr). Forty-eight premolars were selected as enamel specimens and divided randomly into 4 groups (n = 48; n =12) used as antagonists in chewing simulation (250,000 loading cycles) against one of the four selected test materials. Enamel and material specimens were scanned and evaluated under digital microscope, and wear SA (mm2) were recorded. Descriptive statistics, paired t-test, one-way ANOVA, and post-hoc Tukey-HSD tests were used for statistics (p < 0.05). The smallest and largest SA were exhibited by enamel against LD (0.80 mm2) and PFM (1.74 mm2), respectively. PFM (3.48 mm2) showed the largest SA and CR (2.28 mm2) showed the smallest SA. Paired t-test for SA values showed significant difference (p < 0.05) in all wear comparisons between materials and enamel antagonists. The wear of materials were greater than that of their respective enamel antagonists (p < 0.05). One-way ANOVA of the logarithmic means of wear SA revealed significant differences (P<0.05). Post-hoc Tukey test revealed significance for PFM (p < 0.05) with other materials. Wear of all test materials was greater compared to the wear of enamel antagonists. PFM and LD caused the largest and the smallest enamel wear, respectively. CR, LD, and MZr are more resistant than PFM to wear after simulated chewing against enamel.


Assuntos
Resinas Compostas/química , Esmalte Dentário/química , Porcelana Dentária/química , Mastigação , Ligas Metalo-Cerâmicas/química , Desgaste dos Dentes/etiologia , Zircônio/química , Adolescente , Adulto , Análise de Variância , Polimento Dentário/métodos , Humanos , Processamento de Imagem Assistida por Computador , Teste de Materiais , Microscopia/instrumentação , Valores de Referência , Estatísticas não Paramétricas , Propriedades de Superfície , Adulto Jovem
18.
Mymensingh Med J ; 29(1): 228-233, 2020 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-31915363

RESUMO

Reattachment of a fractured fragment to the remaining tooth is challenging but one of the best treatment protocols in regards to aesthetics, function as well as patients acceptance. If the original tooth fragment is retained following fracture, the natural tooth structures can be reattached using adhesive protocols to ensure reliable strength, durability and aesthetics. This case report will discuss a 13 years old boy with a complicated crown-root fracture of maxillary right central incisor tooth. The procedure used to repair the fracture regarding this case including flap surgery with endodontic treatment. The root canal was filled with a root canal sealer and gutta-percha. After root canal obturation, fragment was reattached with an adhesive tooth reattachment technique. After 6 months evaluation, clinical and radiographic examinations showed a stable re-attachment, good aesthetic and healthy periodontium.


Assuntos
Colagem Dentária , Restauração Dentária Permanente/métodos , Incisivo/lesões , Fraturas dos Dentes/terapia , Adolescente , Resinas Compostas , Humanos , Masculino , Maxila , Fraturas dos Dentes/complicações , Resultado do Tratamento
19.
Odontology ; 108(1): 66-73, 2020 01.
Artigo em Inglês | MEDLINE | ID: mdl-31028514

RESUMO

Glass ionomer cement is a widely used luting agent for indirect restorations but presents inferior mechanical properties compared to resin cement due to its low elastic modulus. This study evaluated the mechanical and adhesion properties of glass ionomer luting cements reinforced with nano-sized hydroxyapatite particles (HA). The nano-sized HA particles were synthesized using the co-precipitation technique and the resulting precipitate was characterized using X-ray diffraction analysis (XRD), field emission scanning electron (FESEM) and transmission electron microscopy (TEM). HA particles were incorporated into the glass powder (FUJI I, GC) and the luting agent was manipulated in a liquid to powder ratio of 3:1 into 6% by weight after determining the best ratio. The flexural strength of the luting agent and shear bond strength of dentin were analyzed and compared to other luting agents namely, (a) glass ionomer (FUJI I), (b) resin-modified glass ionomer (RelyX Luting Plus) and (c) adhesive resin cement (RelyX U200). Failure types after debonding from dentin were evaluated under SEM. Flexural strength and bond strength data were analyzed using one-way ANOVA and Tukey's tests (alpha = 0.001). Addition of 6 w % HA particles in the range of 80-150 nm enhanced the flexural strength (30.97 ± 5.9 versus 11.65 ± 5.63) and shear bond strength (0.97 ± 0.41 versus 0.39 ± 0.16) of a conventional glass ionomer luting agent significantly compared to the non-reinforced ones when manipulated at a liquid to powder ratio of 3:1 (P < 0.001). While conventional glass ionomer, HA-reinforced glass ionomer and resin-modified glass ionomer specimens showed exclusively mixed type of failures, adhesive resin cement showed cohesive failures within the resin cement. Increased mechanical and adhesion potential of the experimental glass ionomer luting agent after incorporation of HA particles could expand the scope of application of this cement.


Assuntos
Colagem Dentária , Resinas Compostas , Cimentos Dentários , Durapatita , Cimentos de Ionômeros de Vidro , Teste de Materiais , Cimentos de Resina , Estresse Mecânico , Propriedades de Superfície
20.
Oper Dent ; 45(1): E11-E20, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-31794342

RESUMO

PURPOSE: This randomized clinical trial evaluated the influence of the occlusogingival distance (OGD) of noncarious cervical lesions (NCCLs) on the clinical performance of a regular bulk-fill resin composite and a regular nanofilled resin composite. METHODS AND MATERIALS: A total of 140 restorations were randomly placed in 77 participants by one operator. NCCLs were divided into four groups (n=35) according to OGD (1.5 mm±10% or 3 mm±10%) and resin composites (Filtek Bulk Fill Posterior [B] or Filtek Z350 XT [C]) used: 1.5 mm-B, 1.5 mm-C, 3 mm-B, and 3 mm-C. A two-step self-etch adhesive (Clearfil SE Bond) was applied following manufacturer instructions in all restorative procedures. Restorations were polished 1 week after placement. Clinical evaluation was performed at baseline (7 days), 6 months, and 1 year by two calibrated examiners, according to the modified US Public Health Service criteria evaluating fractures/retention, marginal staining, marginal adaptation, recurrence of caries, anatomic form, postoperative sensitivity, and surface texture. The Kruskal-Wallis test was used for intergroup comparison in each follow-up; the Friedman analysis of variance, followed by the least significant difference test (multiple comparisons) was used for intragroup comparison between baseline and follow-up times (α=0.05). RESULTS: Two restorations were lost at 12 months (1 for 1.5 mm-B and 1 for 3 mm-B). The retention rates at 12 months were 100% for 1.5 mm-C, 97% for 1.5 mm-B, 100% for 3 mm-C; and 97% for 3 mm-B, with no statistical difference among the groups (p=0.570). At 12 months, a statistically significant difference was found among the follow-up times for the same group (1.5 mm-B, 1.5 mm-C, and 3 mm-B) regarding the marginal staining criterion; moreover, the 3 mm-C group showed a significant difference from 6 months. No significant difference was found for the other parameters. CONCLUSION: Both resin composites showed acceptable clinical performance, and the OGD of NCCLs did not influence the clinical performance of resin composite restorations after 12 months.


Assuntos
Cárie Dentária , Restauração Dentária Permanente , Resinas Compostas , Adaptação Marginal Dentária , Humanos , Cimentos de Resina , Propriedades de Superfície
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