Flowable Resin Research Articles

Influence of flowable resins on the shear bond strength of orthodontic brackets

The present study tested the shear bond strength (SBS) of orthodontic brackets bonded to teeth using flowable resins. A total of 105 human teeth were divided into seven groups. The brackets in each group were bonded to the tooth substrates using a Transbond XT adhesive and six other different flowable resins, respectively. Each adhesive resin was light-cured using a quartz-tungsten-halogen (QTH) light for 40 seconds. The brackets were debonded in shear mode using a universal testing machine. The brackets bonded using Tetric Flow and Grandio Flow showed slightly greater SBS values (13.0+/-1.8 and 12.2+/-1.2 MPa, respectively) than the Transbond XT adhesive (12.1+/-1.2 MPa). However, the SBS values of Transbond XT, X-flow, Tetric Flow, Grandio Flow, and Filtek Z350 flow were not significantly different. As for Admira Flow and Aelite Flow, they scored significantly lower SBS values (7.0+/-2.1 and 9.2+/-1.3 MPa, respectively) than the other groups. On bracket failure mode, statistical analysis revealed a similar failure mode among all the seven test groups.

Comparison of marginal microleakage between low and high flowable resins in class V cavity

The purpose of this study was to compare the microleakage of low and high viscosity flowable resins in class V cavities applied with 1-step adhesives. Forty Class V cavities were prepared on the cervices of buccal and lingual surfaces of extracted molar teeth and divided into four groups (n=8). Cavities were restored with AQ Bond Plus /Metafil Flo , G-Bond/ UniFil LoFlo Plus (Low flow groups), AQ Bond Plus/Metafil Flo and G-Bond/UniFil Flow (High flow group), respectively. Specimens were immersed in a 2% methylene blue solution for 24 hours, and bisected longitudinally. They were observed microleakages at the enamel and dentinal margins. In conclusion, the low viscosity flowable resins showed lower marginal microleakage than do the high vis cosity flowable resins in class V cavities.

Effect of an intermediate bonding resin and flowable resin on the compatibility of two-step total etching adhesives with a self-curing composite resin

This study compared the effect of an activator, intermediate bonding resin and low-viscosity flowable resin on the microtensile bond strength of a self-curing composite resin used with two-step total etching adhesives. Twenty extracted permanent molars were used. The teeth were assigned randomly to nine groups (n=10) according to the adhesive system and application of additional methods (activator, intermediate adhesive, flowable resin). The bonding agents and additional applications of each group were applied to the dentin surfaces. Self-curing composite resin buildups were made for each tooth to form a core, 5mm in height. The restored teeth were then stored in distilled water at room temperature for 24h before sectioning. The microtensile bond strength of all specimens was examined. The data was analyzed statistically by one-way ANOVA and a Scheffe’ s test. The application of an intermediate bonding resin (Optibond FL adhesive) and low-viscosity flowable resin (Tetric N-flow) produced higher bond strength than that with the activator in all groups. Regardless of the method selected, Optibond solo plus produced the lowest μ TBS to dentin. The failure modes of the tested dentin bonding agents were mostly adhesive failure but there were some cases showed cohesive failure in the resin. [J Kor Acad Cons Dent 34(5):397-405, 2009]

Effects of non-carious cervical lesions and class V restorations on periodontal conditions

Purpose: The non-carious cervical lesion(NCCL) is a loss of tooth structure at the neck of affected teeth that is unrelated to tooth caries. The reported prevalence of NCCL varies from 5% to 85%. Prevalence and severity of lesions have been found to increase with age. They are becoming more significant as people live longer and become more aware of the importance of oral health. The purposes of this study were first, to examine the periodontal conditions associated with NCCL, and second, to investigate the clinical effects of class Ⅴ restorations of NCCL on periodontal tissues. Materials and methods: The sample size was 982 teeth of 50 subjects(25 male, mean age 52±7) who were seen at the Department of Periodontology, Pusan National University Hospital. At the baseline examination, clinical periodontal parameters were measured. After the initial examination, 24 patients who were absent from hypersensitivity were selected. The teeth with NCCL were randomly divided into the test and control groups. The teeth in the test group were restored with flowable resin; the control teeth were not restored. Six months later, the clinical examinations were repeated. The data were analyzed using the SPSS program. Results: The results were as follows: 1) NCCL occurred on 45.8% of examined teeth. The percentage of affected teeth was higher in maxillary and premolar teeth. 2) The shallow saucer type was the most common. 3) Teeth with NCCL had more gingival recession, lower attachment level, and higher incidences of bleeding on probing(BOP) and plaque than NCCL-free teeth. 4) Six months later, gingival recession, attachment level, the percentages of BOP and plaque in the test group were lower than in the control group(p<0.05). Conclusion: NCCLs were more found in maxillary teeth, especially in premolar teeth. The results suggest that the restoration of NCCL could affect some periodontal parameters favorably. (J Korean Acad Periodontol 2009;39:17-26)

Morphological analysis of flowable resins after long-term storage or surface polishing with a mini-brush

This study evaluated the surface roughness and morphological changes of various flowable resins after long-term storage in a phosphate-buffered saline (PBS) or surface polishing with a mini-brush. The tested products were Beautifil Flow BF02 and BF10, Clearfil Majesty LV, Filtek Supreme XT, and UniFil LoFlo Plus. A paste-type resin composite, Filtek Supreme, was used as a control. The prepared specimens were 10 mm in diameter and 1 mm in height. The standard surfaces were polished with #600-1200 diamond disks and kept in deionized water for 24 hours. Surface roughness was detected after storage in PBS (pH 7.4) for either 2 weeks or 6 months, or after polishing with a mini-brush. Results of this study demonstrated that the surface roughness of the standard specimens had a lower value as compared to those after storage in PBS for 2 weeks and 6 months, or after polishing with a mini-brush.

Comparison of microleakage after load cycling for nanofilled composite resin fillings with or without flowable resin lining

I. 서론 = 1 II. 실험 재료 및 방법 = 4 1. 재료 = 4 1) 치아 = 4 2) 레진 접착제 = 4 3) 레진 = 4 4) 광중합기 = 6 2. 치아삭제와 충전 = 6 3. 반복부하실험 = 8 4. Statistical analysis = 10 III.연구 결과 = 11 IV.총괄 및 고찰 = 17 V. 결론 = 20 참고 문헌 = 21 Abstract = 24

Evaluation of the Surface Structure of a Newly Developed Flowable Resin Composite : Influence of Acidic and Alcoholic Drinks

Evaluation of the Surface Structure of a Newly Developed Flowable Resin Composite : Influence of Acidic and Alcoholic Drinks

Slumping tendency and rheological property of flowable composites

The aim of this study was to develop a method for measuring the slumping resistance of flowable resin composites and to evaluate the efficacy using rheological methodology. Five commercial flowable composites (Aelitefil flow:AF, Filtek flow:FF, DenFil flow:DF, Tetric flow:TF and Revolution:RV) were used. Same volume of composites in a syringe was extruded on a glass slide using a custom-made loading device. The resin composites were allowed to slump for 10 seconds at and light cured. The aspect ratio (height/diameter) of cone or dome shaped specimen was measured for estimating the slumping tendency of composites. The complex viscosity of each composite was measured by a dynamic oscillatory shear test as a function of angular frequency using a rheometer. To compare the slumping tendency of composites, one way-ANOVA and Turkey's post hoc test was performed for the aspect ratio at 95% confidence level. Regression analysis was performed to investigate the relationship between the complex viscosity and the aspect ratio. The results were as follows. 1. Slumping tendency based on the aspect ratio varied among the five materials (AF

Effects of sonic scaling on the surface roughness of restorative materials

The surface roughness of dental restorative materials has a crucial effect on the health of dental and periodontal tissues as well as for the longevity of restorations. In this study we tested a glass ionomer restorative cement, two nanohybrid resin composites, a flowable resin composite and a silorane-based composite. Twenty cylindrical specimens of each material were prepared, cured, polished and instrumented with a sonic scaler (Alegra ST ZE-55 RM W&H, Austria). The mean surface roughness was recorded using a profilometer (SJ-201, Mitutoyo, Japan) at three stages: before scaling, after scaling and after re-polishing. Additional specimens were analyzed by scanning electron microscopy and back-scattered imaging. Data were examined statistically by analysis of variance (ANOVA) and post-hoc tests at a level of significance of P < 0.05. The profilometric measurements and the SEM evaluation showed that, in most of the materials tested, the surface roughness was significantly increased after sonic instrumentation. After re-polishing the specimens, the roughness values were decreased. Periodontal scaling should include polishing of restorations in order to overcome alterations in surface roughness.

Contemporary Use of Flowable Resin Composite Materials

Flowable resin composite materials have become established as part of the restorative dentist's portfolio since their introduction to the market some 12 years ago. Their properties and clinical handling are different owing to their chemical and structural composition when compared to conventional resin composite materials and their advantages and shortcomings must be understood for their clinical use to be effective. This paper explains the effect of their differing composition and the clinical ramifications of this. It reviews these materials' indications and contra-indications and provides practical advice on their usage. Flowable resin composite materials are widely used in restorative dentistry and the clinician should understand the advantages and shortcomings of the properties of each restorative material in order to maximize clinical success.

Evaluation of the dental structure loss produced during maintenance and replacement of occlusal amalgam restorations

The aim of this in vitro study was to evaluate four different approaches to the decision of changing or not defective amalgam restorations in first primary molar teeth concerning the loss of dental structure. Ditched amalgam restorations (n = 11) were submitted to four different treatments, as follows: Control group - polishing and finishing of the restorations were carried out; Amalgam group - the ditched amalgam restorations were replaced by new amalgam restorations; Composite resin group - the initial amalgam restorations were replaced by composite resin restorations; Flowable resin group - the ditching around the amalgam restorations was filled with flowable resin. Images of the sectioned teeth were made and the area of the cavities before and after the procedures was determined by image analysis software to assess structural loss. The data were submitted to ANOVA complemented by the Student Newman Keuls test (p < 0.05). The cavities in all the groups presented significantly greater areas after the procedures. However, the amalgam group showed more substantial dental loss. The other three groups presented no statistically significant difference in dental structure loss after the re-treatments. Thus, replacing ditched amalgam restorations by other similar restorations resulted in a significant dental structure loss while maintaining them or replacing them by resin restorations did not result in significant loss.

Management of subluxation injury in a thumb‐sucking child: a case report

This case report presents use of a custom trauma splint that was fabricated to prevent excessive thumb-sucking trauma to a previously-subluxated permanent incisor. A 10-year-old boy was referred to the clinic 10 days after falling in the schoolyard that resulted in a trauma to his maxillary left central incisor. The extent of clinical mobility stipulated fabrication of a custom trauma splint that would prevent further trauma to the incisor caused by excessive pressure of the thumb. A light-cured resin composite splint, covering the incisal edges of the central incisors and labial surfaces of the lateral incisors was made, and approximately 1-mm composite within the impressions of central incisors were trimmed off. The splint was bonded to the neighboring lateral incisors with flowable resin composite and root canal therapy was initiated on the subluxated incisor. After one week, the patient stopped his sucking habit completely. The treatment not only allowed for complete healing of the subluxated incisor without being exposed to further trauma, but also for spontaneous eruption of the tooth and closure of the existing open-bite.

Differences in color, translucency and fluorescence between flowable and universal resin composites

Objectives To evaluate the optical properties such as color, translucency and fluorescence of flowable resin composites, and compare them with the corresponding shade universal resin composites of the same brand. Methods Four brands of flowable and universal resin composites of the same shade designation (A2) were investigated. Color of specimens (2 mm in thickness) was measured after polymerization on a reflection spectrophotometer over background of white, black and each corresponding composite material itself. Color differences ( Δ E ab * ) between each combination of resin composites were determined. Translucency parameter (TP) and color difference by the fluorescent emission ( Δ E ab * -FL ) of materials were also calculated. Differences in the optical properties of flowable and universal resin composites were analyzed with one-way ANOVA. Results Δ E ab * between the flowable and the corresponding universal resin composites was in the range of 1.0–6.0 Δ E ab * units, which was perceptible ( Δ E ab * > 2.6 ) in three brands. Flowable resin composites revealed lower TP values in two of the four brands. Δ E ab * between flowable and the corresponding universal resin composites was influenced by their difference in translucency. All the four universal resin composites and two flowable resin composites showed fluorescent peak, and the range of Δ E ab * -FL was 0.3–2.3 Δ E ab * units. Conclusions Optical properties of flowable and universal resin composites was significantly different ( p < 0.05); therefore, differences in color, translucency and fluorescence between the flowable and the corresponding universal resin composites should be considered for clinically acceptable color matching.

Rheological properties of experimental Bis-GMA/TEGDMA flowable resin composites with various macrofiller/microfiller ratio

Objectives The purpose of this study was to investigate the rheological behavior of resin composites and to evaluate the influence of each component, organic as well as inorganic, on their viscoelastic properties by testing model experimental formulations. Methods Several unfilled mixtures of 2,2-bis-[4-(methacryloxy-2-hydroxy-propoxy)-phenyl]-propane (Bis-GMA) and triethylene glycol dimethacrylate (TEGDMA) were prepared as well as experimental flowable resin composites using a Bis-GMA/TEGDMA 50/50 wt% mixture as organic fraction filled at 60% in weight with varying ratios of silanated barium glass (1 μm) and partially hydrophobic fumed silica (0.1 μm). Their rheological properties were investigated using dynamic oscillatory rheometers. Transmission electron microscopy (TEM) was also performed to investigate the spatial organization of the filler particles. Results Unfilled Bis-GMA/TEGDMA mixtures all showed a Newtonian behavior. The experimental flowable resin composites were non-Newtonian, shear-thinning fluids. As the quantity of microfiller increased, the viscosity increased and the shear-thinning behavior increased as well. In addition, the experimental composites showed thixotropy, i.e. their viscosity is a function of time after deformation. All these properties were not specifically linked to the creation and destruction of a visible network between inorganic particles, as no difference could be seen between particles’ spatial organization at the equilibrium rest state or immediately after deformation. Significance The complex viscoelastic properties of resin composites are due to interactions between microfiller and monomer molecules. Modifying the chemical and physical properties of the particles’ surface could possibly improve their flow properties and thus their clinical handling performances.

SIMPLE FIXED SPACE MAINTAINER BONDED WITH FLOWABLE RESIN COMPOSITE IN PREMATURE LOSS OF MAXILLARY FIRST PRIMARY MOLAR

The premature loss of primary teeth will make the adjacent tooth drift due to the mesial force of the erupting posterior teeth in the growing child. To overcome this problem a space maintainer is needed. But, space maintainer needs to undergo a laboratorial process, which means needing more time and money. This paper reported a case with premature loss of maxillary first primary molar using space maintainer which can be used immediately, easy to do, and need low cost, a simple fixed space maintainer bonded with flowable resin composite.

Weibull analysis of shear/peel bond strength of orthodontic buccal tubes bonded to five resin composites

Bonding orthodontic buccal tube on a large resin composite restoration of molar tooth can result in easier bond failure than bonding to intact enamel. The resin composite type may be one of several factors that influence the bond strength. The objective of this study was to analyze the survival probabilities of buccal tubes bonded to various resin composites. Resin composite discs, 33 specimens for each group were prepared as follows: (1) nanofill (Filtek Supreme), (2) compomer (F2000), (3) hybrid (Z100), (4) packable (P60) and (5) flowable (Filtek Flow). The surface was etched with 9.6% hydrofluoric acid, followed by plastic conditioner application. Orthodontic buccal tubes were then bonded. Shear/peel bond strength was tested with the universal testing machine. The Weibull analysis was performed to indicate the survival probability for each resin composite type. Scanning electron microscope comparison of unetched and etched surface of resin composite was demonstrated. The probabilities of survival at a stress level of 7.8 MPa ranked from highest to lowest as follows: hybrid (95.87%), packable (95.38%), flowable (91.81%), compomer (69.95%) and nanofill (36.03%). The survival probabilities of orthodontic buccal tube bonded on hybrid, packable and flowable resin composite were substantially high, while that of nanofill resin composite was remarkably low. From scanning electron microscope, different surface topography of etched surface exhibited unequal resistance to acid etching among different resin composites. Therefore, type of resin composite surface accounted for the differences seen in the survival probabilities of orthodontic buccal tubes.

Evaluation of success in the reattachment of coronal fractures

The aim of this study was to evaluate clinically and radiographically the restored teeth using reattachment technique of fractured fragment to the remaining tooth. This study was conducted on 11 children (six girls and five boys; age range: 8-13 years). Before the treatment, the teeth were evaluated clinically and radiographically. The broken incisal part was directly reattached to the remaining tooth part with flowable resin composite. Thereafter, with the purpose of obtaining optimal esthetics and function, along the fracture line an external 'double chamfer' in the shape of a V was created and then covered with resin composite. During the follow-up (1-24 months) after the treatment, the teeth were evaluated clinically and/or radiographically with regard to periodontal, pulpal, coronal, color harmony of the fragments, and occlusion. In addition, the restored teeth were assessed in terms of parental-patient ratings of satisfaction. Both clinically and radiographically, no pathology was reported and all the restorations were successful. Moreover, the mean scores of parental-patient satisfaction were reported as 'satisfied, very-satisfied.'

Survival of flexible, braided, bonded stainless steel lingual retainers: a historic cohort study

The objectives of this study were to retrospectively evaluate the clinical survival rate of flexible, braided, rectangular bonded stainless steel lingual retainers, and to investigate the influence of gender, age of the patient, and operator experience on survival after orthodontic treatment at the Department of Orthodontics, University of Groningen, between the years 2002 and 2006. The study group comprised of 277 patients [162 females: median age 14.8 years, interquartile range (IQR) 13.6-16.5 years and 115 males: median age 15.3 years, IQR 14.2-16.7 years]. After acid etching the lingual surfaces of each tooth, an adhesive resin was applied and retainers were bonded using a flowable resin composite. Data concerning, failures, gender, age of the patient, and operator experience were retrieved from the patient files that were updated by chart entries every 6 months or when failure was reported by the patient. The maximum follow-up period was 41.7 months. All 277 patients received flexible, braided, bonded mandibular canine-to-canine retainers. Eighteen failures were observed in the maxilla. A failure was recorded when there was debonding, fracture, or both, occurring in one arch. Only first failures were used for statistical analysis. When failures occurred in both jaws, these were considered as two separate incidences. Ninety-nine debonding (35.7 per cent), two fractures (0.7 per cent), and four debonding and fracture (1.4 per cent) events were observed. No significant effect (P > 0.05) of gender (females: 41 per cent, males: 32 per cent) or patient age (<16 years: 37 per cent, > or =16 years 38.7 per cent) was observed. The failure rate did not differ due to operator experience (n = 15; less experienced: 38.0 per cent; moderately experienced: 28.9 per cent, professional: 46.7 per cent; P > 0.05; chi-square test). Kaplan-Meier survival curves showed a 63 per cent success rate for the bonded lingual retainers over a 41.7 month period.

Evaluation of Flowable Resin Composite Surfaces Eroded by Acidic and Alcoholic Drinks

The purpose of this study was to evaluate the morphological changes of the surfaces of flowable resins eroded by orange juice and alcohol drinks. The tested products were Beautifil Flow BF02 and BF10, Clearfil Majesty LV, Filtek Supreme XT Flowable Restorative, Unifil LoFlo Plus and Filtek Supreme. Filler percentages of flowable resins were calculated after the latter were incinerated at 750 degrees C. Specimens were shaped into a disk form with a diameter of 10 mm and a thickness of 1 mm. Morphological changes were evaluated for the following types of flowable resin surfaces: polished surface, surfaces eroded by 100% orange juice, wine and whisky. Filler percentages of the tested flowable resins ranged between 42 and 78%. Surface degradation was observed for the specimens immersed in acidic and alcoholic drinks, and it was thought that the lower the filler percentage, the greater was the surface degradation. Decomposition of the matrix resin and fallout of the fillers were observed in flowable resins that eroded with acidic and alcoholic drinks.

The influence of combining composite resins with different elastic modulus on the stress distribution of Class V restoration: a three-dimensional finite element study

This study was to investigate the influence of combining composite resins with different elastic modulus, and occlusal loading condition on the stress distribution of restored notch-shaped non-cari- ous cervical lesion using 3D finite element (FE) analysis. The extracted maxillary second premolar was scanned serially with Micro-CT. The 3D images were processed by 3D-DOCTOR. ANSYS was used to mesh and analyze 3D FE model. A notch-shaped cavity was modeled and filled with hybrid, flowable resin or a combination of both. After restora- tion, a static load of 500N was applied in a point-load condition at buccal cusp and palatal cusp. The stress data were analyzed using analysis of principal stress. Results showed that combining method such that apex was restored by material with high elastic modulus and the occlusal and cervical cavosurface margin by small amount of material with low elastic modulus was the most profitable method in the view of tensile stress that was considered as the dominant factor jeopardizing the restoration durability and promoting the lesion progression. (J