RESUMO
The study verified the influence of calcium orthophosphate (CaP):glass ratio on the degree of conversion and mechanical properties of resin-based composites containing either TEGDMA-functionalized dicalcium phosphate anhydrous (DCPA) or non-functionalized DCPA particles. The null hypotheses were that the evaluated variables are not affected by (1) CaP:glass ratio or (2) DCPA functionalization. DCPA particles were synthesized and half of them were functionalized with TEGDMA. Particle characterization included x-ray diffraction, elemental analysis, laser scattering, helium picnometry and scanning electron microscopy. Two series of composites were prepared containing either DCPA-NF (non-functionalized) or DCPA-F (functionalized), with total inorganic content of 50 vol % and DCPA:silanized barium glass (BG) ratios from 10:40 to 50:0. A composite containing 50 vol % BG was tested as control. DC was determined using FTIR spectroscopy. Biaxial flexural strength and modulus were tested after 24 h in water. Data were analyzed using Kruskal-Wallis/Dunn (flexural properties) or analysis of variance/Tukey tests (DC). Materials with similar actual DCPA contents were compared using Student's t test (alpha: 0.05). DC was higher for materials with DCPA-F, except for the 10:40 ratio. DCPA-F resulted in higher strength than DCPA-NF only at 40:10 ratio. Modulus was not affected by functionalization. Materials with similar actual DCPA contents showed differences in DC (F > NF), while no difference in flexural properties was observed between materials with 28%-30% DCPA. Both null hypotheses were rejected.
Assuntos
Cálcio , Fosfatos , Humanos , Resinas Compostas/química , Teste de Materiais , Materiais Dentários , Propriedades de SuperfícieRESUMO
OBJECTIVES: This retrospective study evaluated the performance of posterior composites after up to 33 years of clinical service and investigated factors associated with the risk of failures over time including patient- and tooth-related variables. METHODS: Patients who received at least one Class I or Class II direct composite restoration in a private office in 1986-1992 and had follow-up appointments were included. Failures and interventions over time were investigated using the dental records. A follow-up clinical recall was carried out in 2020. Two scenarios were considered: restorations that did not require any intervention (success) or restorations that were repaired and still functional (survival). Multivariate Cox regression analyses and Kaplan-Meier curves were performed using success and survival rates (p < 0.05). RESULTS: One hundred patient records and 683 restorations were included. A total of 353 failures were reported (success rate= 48%). Main reasons for failure were fracture and secondary caries. Most interventions after failures were repairs. Replacements were registered in 183 cases (survival rate= 73%). Annual failure rates were below 2.5% (success) and 1.1% (survival). Larger restorations and maxillary molars had higher failure risks. No significant differences in success rates among different resin composites was observed. A typical observation in this sample of restorations was the presence of moderate to advanced signs of aging, including marginal and surface staining, wear, chipping, changes in anatomical shape and translucency. Clearly aged restorations were still clinically satisfactory. SIGNIFICANCE: This long-term, practice-based study indicates that resin composites can be used to restore posterior teeth with a long-lasting durability.
Assuntos
Cárie Dentária , Restauração Dentária Permanente , Idoso , Resinas Compostas , Falha de Restauração Dentária , Humanos , Estudos RetrospectivosRESUMO
OBJECTIVE: To evaluate coating materials regarding color and roughness changes when applied over a composite resin. MATERIALS AND METHODS: Specimens were made using Filtek Supreme Ultra. Coating materials were applied over the specimens' surface: Control (CTRL); Adper Single Bond Plus (SB); Scotchbond Universal (US); Clearfil SE (CL); Ambar APS (APS); Bioforty (BF); Fortify (FF); PermaSeal (PS); G-CoatPlus (GC). Specimens were evaluated regarding color changes (∆E00 ) using spectrophotometer (n = 10); surface roughness (Ra), using optical profilometer (n = 10); surface topography, using scanning electron microscopy (n = 1); and thickness of material, using optical microscopy (n = 1). Analyses were made before and after 24, 72, and 168 hours of storage in wine, used as a staining solution. Data was statistically analyzed using analysis of variance, Tukey and Pearson tests (α:.05). RESULTS: None of the materials presented color stability. ∆E00 increased with increasing storage time at red wine, until 72 hours. BF, FF, PS, SB, and CTRL presented the lowest ∆E00 after 24 hours. APS presented the highest ∆E00 (32.59; P < .05). Regarding roughness, initially, surface sealants and APS presented the lowest values. After 168 hours, GC presented the lowest Ra (0.60; P < .05). CONCLUSIONS: All the materials presented color and roughness changes after storage in red wine. CLINICAL RELEVANCE: Some coating materials can be applied over the surface of RBC restorations without changing its color stability or surface roughness.
Assuntos
Resinas Compostas , Cimentos Dentários , Cor , Materiais Dentários , Teste de Materiais , Espectrofotometria , Propriedades de SuperfícieRESUMO
The purpose of this study was to compare the linear polymerization shrinkage of different restorative resin-based composites (RBCs) using fiber Bragg grating (FBG) sensors. Five RBCs were evaluated: Zirconfill® (ZFL); Aura Bulk-Fill (ABF); Tetric® N-Ceram Bulk-Fill (TBF); FiltekTM Bulk-Fill (FBF); and Admira Fusion-Ormocer® (ADF). Ten samples per resin were produced in standardized custom-made half-gutter silicone molds. Two optical FBG sensors were used to assess temperature and polymerization shrinkage. Light curing was performed for 40 s and polymerization shrinkage was evaluated at 5, 10, 40, 60, 150, and 300 s. Statistical analysis was accomplished for normal distribution (Shapiro-Wilk, p > 0.05). Two-way repeated measures ANOVA with Greenhouse-Geisser correction followed by Bonferroni's post-hoc test was used to analyze the linear shrinkage data (p < 0.05). ZFL showed the highest linear shrinkage and ADF the lowest. Shrinkage increased for all RBCs until 300 s, where significant differences were found between ADF and all other resins (p < 0.05). Among bulk-fill RBCs, TBF showed the lowest shrinkage value, but not statistically different from FBF. The ADF presented lower linear shrinkage than all other RBCs, and restorative bulk-fill composites exhibited an intermediate behavior.
RESUMO
OBJECTIVE: To evaluate the effect of ionizing radiation from high energy X-ray on properties of restorative materials. METHODS: Study materials (3M-ESPE) were: Z250-microhybrid resin-based composite (Filtek Z-250); Z350-nanofilled resin-based composite (Filtek Z-350XT); VIT-resin-modified glass ionomer cement (Vitremer); and KME-conventional glass ionomer cement (Ketac Molar Easymix). Sixty bar-shaped and cylinder-shaped specimens were fabricated from each material. Specimens were light activated (980mW/cm2, Radii, SDI) for 60s (3×20s for Z250 and Z350) and 120s (3×40s for VIT) and thirty specimens from each shape were irradiated (IR) with 1.8Gy/day for 39days (total IR=70.2Gy). IR and non-irradiated (NI) specimens were evaluated for flexural strength (σ, n=30) followed by fractography (SEM), diametral tensile strength (DTS, n=30), hardness (H, n=10), surface roughness (Ra, n=10) and chemical composition (n=3). The IR effect on each material property was statistically analyzed using Student's t test (α=0.05). Data from σ and DTS were also analyzed using Weibull statistics. RESULTS: IR significantly increased the mean σ values of VIT and KME and the mean DTS value of VIT (p<0.05). IR increased Ra and H values for VIT and decreased H value for Z-250 (p<0.05). The remaining materials and properties were not significantly affected by IR (p>0.05). There was no significant change on materials composition after IR. SIGNIFICANCE: The recommended radiotherapy protocol for head and neck cancer altered some material properties, mainly for glass ionomer cements. Such variations on material properties are not related to chemical composition changes.
Assuntos
Resinas Compostas/efeitos da radiação , Materiais Dentários/efeitos da radiação , Cimentos de Ionômeros de Vidro/efeitos da radiação , Radiação Ionizante , Resinas Compostas/química , Materiais Dentários/química , Cimentos de Ionômeros de Vidro/química , Teste de Materiais , Propriedades de Superfície , Resistência à TraçãoRESUMO
ABSTRACT. Introduction: the goal of this literature review is to analyze the findings included in the literature concerning different alternatives to increase longevity of resin-based composite restorations and their adhesive bond. Methods: bibliographies in the EBSCO database (Elton B Stephens Company) were reviewed using the following key words: "composite repair bond strength"; "restorations sealing"; composite restorations longevity"; "restorations refurbishment"; "composite bond strategy"; "dental adhesive collagen cross linking"; "proanthocyanidin dentin bond strength"; "multiple layer dentin bond strength", and "dentin adhesive evaporation bond strength". Clinical and laboratory results were analyzed in terms of repairing, sealing, and refurbishing defective restorations, in addition to improvements in impregnation of adhesive surfaces, resistance of adhesive polymers, and the progress recently made concerning resistance to hydrolytic collagen degradation. Results: repairing, sealing, or refurbishing defective restorations allow keeping tooth structure healthy, reducing potential damage to dental pulp, as well as operatory pain, often caused without anesthetics. New bonding management techniques provide adhesive procedures with increased longevity. Conclusions: repairing, refurbishing, or sealing defective composite resins increase the longevity of restorations and restored teeth by using minimally invasive dental techniques. Other methods, such as improving impregnation of adhesive surfaces, increasing adhesive polymers strength, and hydrolytic degradation of collagen are promising advances that modify the management of bonding techniques, providing patients with restorative treatments of increased longevity.
RESUMEN. Introducción: el objetivo de esta revisión es analizar los resultados de las diferentes alternativas que presenta la literatura para incrementar la longevidad de las restauraciones con base a resinas compuestas. Métodos: fueron revisadas las bibliografías en la base de datos EBSCO (Elton B Stephens Company), en idioma inglés bajo los siguientes acrónimos " composite repair bond strengh"; "restorations sealing"; composite restorations longevity; "restorations refurbishment"; "composite bond estrategy"; "dental adhesive collagen cross linking"; "proanthocyanidin dentin bond strength";" multiple layer dentin bond strength"; and "dentin adhesive evaporation bond strength". Se examinan los resultados clínicos y de laboratorio de reparación, sellado y remodelado de restauraciones defectuosas, además de las mejoras en la impregnación de las superficies adhesivas, la resistencia de los polímeros adhesivos y los avances en el aumento de la resistencia a la degradación hidrolítica del colágeno. Resultados: la reparación, sellado y remodelado de restauraciones defectuosas permite la preservación de estructura dentaria sana, reducción del potencial daño a la pulpa dental y reducción del dolor operatorio, la mayoría de las veces efectuado sin uso de anestésicos. Nuevas técnicas para el manejo de la adhesión proporcionan incremento en la longevidad de los procedimientos adhesivos. Conclusiones: la reparación, remodelado y sellado de resinas compuestas defectuosas, incrementa la longevidad de las restauraciones y de los dientes restaurados con la aplicación de técnicas de odontología mínimamente invasiva. Adicionalmente otras metodologías, tales como mejoras en la impregnación de las superficies adhesivas, aumento de la resistencia de los polímeros adhesivos e incremento de la resistencia a la degradación hidrolítica del colágeno constituyen promisorios avances que modifican el manejo de las técnicas adhesivas, que permitirá ofrecer tratamientos restauradores de mayor longevidad a la población.
Assuntos
Reparação de Restauração Dentária , Resinas Compostas , Dentística Operatória , LongevidadeRESUMO
The most common treatment in general dental practice is the replacement of restorations affected by secondary caries or marginal deficiencies. Alternative treatments to replacement of defective restorations, such as marginal sealing, refurbishment and repair, have demonstrated improvement of their clinical properties with minimal intervention. The aim of this clinical study was to estimate the median survival time (MST) of marginal sealing, repair and refurbishment of amalgam and resin-based composite restorations with localized defects as a treatment to increase the restoration longevity. A cohort of 66 patients, with 271 class I and II restorations clinically diagnosed with localized defects was longitudinally assessed. Each restoration was assigned to one of the following 5 groups: Marginal Sealing (n=48), Refurbishment (n=73), Repair (n=27), Replacement (n=42), and Untreated (n=81). Two calibrated examiners assessed the restorations at baseline and annually during 4 years, using the modified Ryge criteria: marginal adaptation, anatomic form, roughness, secondary caries and luster. Fifty-two patients with 208 restorations were assessed after 4 years; the distribution of restorations in the groups was as follows: Marginal Sealing (n=36), Refurbishment (n=63), Repair (n=21), Replacement (n=28) and Untreated (n=60). Kaplan Meier test indicated that the Sealed margins group showed the lowest MST while the Repair group showed the highest MST for restorations examined after 4 years of follow up. Defective amalgam and resin-based composite restorations treated by sealing of marginal gaps, refurbishment of anatomic form, luster or roughness, and repair of secondary caries lesions, had their longevity increased.
Na clínica odontológica geral, o tratamento mais comum é a substituição de restaurações com cárie secundária ou defeitos marginais. Tratamentos alternativos às substituições de restaurações defeituosas, como selamento marginal, recuperação, e reparo, têm proporcionado melhorias das propriedades clínicas, com um mínimo de intervenção. O objetivo deste estudo foi avaliar o tempo médio de sobrevida (median survival time - MST, na sigla em inglês) de selamento marginal, recuperação e reparo de restaurações de amálgama e compósitos resinosos com defeitos localizados, como tratamento para aumentar a longevidade das restaurações. Este foi um estudo longitudinal envolvendo 66 pacientes com 271 restaurações classe I e II, clinicamente diagnosticadas e com defeitos localizados. Cada restauração foi incluída num dos seguintes grupos: Selamento Marginal (n=48), Recuperação (n=73), Reparo (n=27), Substituição (n=42) e Sem tratamento (n=81). Dois examinadores calibrados avaliaram as restaurações no início e anualmente durante 4 anos, usando os critérios de Ryge modificados: adaptação marginal, forma anatômica, rugosidade, cárie secundária e brilho. Cinqüenta e dois pacientes com 208 restaurações foram avaliados após 4 anos; a distribuição das restaurações nos grupos foi a seguinte: Selamento Marginal (n=36), Recuperação (n=63), Reparo (n=21), Substituição (n=28) e Sem tratamento (n=60). O teste de Kaplan Meier mostrou que o grupo do Selamento Marginal apresentou o menor valor de MST, enquanto que o grupo do Reparo mostrou o maior valor, para as restaurações avaliadas após o acompanhamento de 4 anos. As restaurações de amálgama e compósitos tratadas com selamento de fissuras marginais, recuperação da forma anatômica, brilho ou rugosidade e reparo de cárie secundária, tiveram aumento de longevidade.