Composite resins

In case of severe dental erosion, the maxillary anterior teeth are often particularly affected. Restoring such teeth conventionally (ie, crowns) would frequently involve elective endodontic therapy and major additional loss of tooth structure. A novel, minimally invasive approach to restore eroded teeth has been developed and is currently being tested in the form of a prospective clinical trial, termed The Geneva Erosion Study. To avoid crowns, two separate veneers with different paths of insertion have been used to restore the affected anterior maxillary teeth, regardless of clinical crown length and amount of remaining enamel. This treatment is called The Sandwich Approach. The purpose of this case series study was to analyze the mid-term clinical outcome of maxillary anterior teeth affected by severe dental erosion that were restored following the Sandwich Approach. Twelve consecutively consulting patients (mean age: 39.4 years) suffering from advanced dental erosion have been en...

ABSTRACTPurpose:: The purpose of this study was to determine the wear resistance of five different packable composites versus two different composite controls using a laboratory toothbrushing simulation test.The purpose of this study was to determine the wear resistance of five different packable composites versus two different composite controls using a laboratory toothbrushing simulation test.Materials and Methods: Twelve samples measuring 5 mm in diameter and 3 mm thick were prepared from the following resin composites: Packable resin composites SureFil® (Dentsply Ind. Com. Ltda, Petrópolis, Rio de Janeiro, Brazil), Alert® (Jeneric Pentron Incorporated, Wallingford, CT, USA), Filtek P60™ (3M ESPE Dental Products, St. Paul, MN, USA), Prodigy Condensable® (sds Kerr, Orange CA, USA), Solitaire® (Heraeus Kulzer GmbH, Wehrheim, Germany), and control resin composites Z100 Restorative™ (3M ESPE) and Silux Plus™ (3M ESPE). Finishing and polishing were conducted with Sof-Lex™ disks (3M ESPE), and baseline weight (grams) and surface roughness (measured with Hommel Tester® T 1000, Hommelwerke, GmbH, Alte Tuttinger Strebe 20. D-7730 VS-Schwenningen, Germany) were recorded. Specimens were aged for 2 weeks until they reached a weight that remained constant for 5 consecutive days, and then were subjected to 100,000 cycles of brushing (representative of 4.2 yr) using a toothbrushing testing machine. Toothbrush heads with soft bristle tips (Colgate Classic™, Colgate-Palmolive Co., Osasco, São Paulo, Brazil) with dentifrice suspension (Colgate MFP™, Colgate-Palmolive Co.) in deionized water were used under a 200 g load. Changes in weight and surface roughness were determined after toothbrushing cycles.Twelve samples measuring 5 mm in diameter and 3 mm thick were prepared from the following resin composites: Packable resin composites SureFil® (Dentsply Ind. Com. Ltda, Petrópolis, Rio de Janeiro, Brazil), Alert® (Jeneric Pentron Incorporated, Wallingford, CT, USA), Filtek P60™ (3M ESPE Dental Products, St. Paul, MN, USA), Prodigy Condensable® (sds Kerr, Orange CA, USA), Solitaire® (Heraeus Kulzer GmbH, Wehrheim, Germany), and control resin composites Z100 Restorative™ (3M ESPE) and Silux Plus™ (3M ESPE). Finishing and polishing were conducted with Sof-Lex™ disks (3M ESPE), and baseline weight (grams) and surface roughness (measured with Hommel Tester® T 1000, Hommelwerke, GmbH, Alte Tuttinger Strebe 20. D-7730 VS-Schwenningen, Germany) were recorded. Specimens were aged for 2 weeks until they reached a weight that remained constant for 5 consecutive days, and then were subjected to 100,000 cycles of brushing (representative of 4.2 yr) using a toothbrushing testing machine. Toothbrush heads with soft bristle tips (Colgate Classic™, Colgate-Palmolive Co., Osasco, São Paulo, Brazil) with dentifrice suspension (Colgate MFP™, Colgate-Palmolive Co.) in deionized water were used under a 200 g load. Changes in weight and surface roughness were determined after toothbrushing cycles.Results: Significant differences of weight loss and surface roughness were found (paired t-test, p < .05). Weight loss percentage (mean [SD]) ranged from 0.38 to 1.69% (analysis of variance and Tukey's least significant difference, p < .05); the weight loss of the materials ranked from least to most as follows: SureFil (0.38 [0.56]), Alert (0.52 [0.18]), Z100 (1.16 [0.27]), Filtek P60 (1.31 [0.17]), Solitaire (1.51 [0.45]), Prodigy Condensable (1.55 [0.47]), and Silux Plus (1.69 [0.66]). Regarding surface roughness, Prodigy Condensable (0.19 [0.08]), Solitaire (0.28 [0.06]), and Z100 (0.30 [0.07]) became less rough after toothbrushing, whereas all the others were rendered rougher: Alert (0.49 [0.29]), Filtek P60 (0.28 [0.08]), Silux Plus (0.39 [0.09]), and SureFil (0.81 [0.32]).Significant differences of weight loss and surface roughness were found (paired t-test, p < .05). Weight loss percentage (mean [SD]) ranged from 0.38 to 1.69% (analysis of variance and Tukey's least significant difference, p < .05); the weight loss of the materials ranked from least to most as follows: SureFil (0.38 [0.56]), Alert (0.52 [0.18]), Z100 (1.16 [0.27]), Filtek P60 (1.31 [0.17]), Solitaire (1.51 [0.45]), Prodigy Condensable (1.55 [0.47]), and Silux Plus (1.69 [0.66]). Regarding surface roughness, Prodigy Condensable (0.19 [0.08]), Solitaire (0.28 [0.06]), and Z100 (0.30 [0.07]) became less rough after toothbrushing, whereas all the others were rendered rougher: Alert (0.49 [0.29]), Filtek P60 (0.28 [0.08]), Silux Plus (0.39 [0.09]), and SureFil (0.81 [0.32]).Conclusion: SureFil and Alert were statistically more resistant to wear (less weight loss) than were the other materials. SureFil became significantly rougher than did all the others.SureFil and Alert were statistically more resistant to wear (less weight loss) than were the other materials. SureFil became significantly rougher than did all the others.

The role of prosthetic restorations in the final appearance of the surrounding soft tissues has long been recognized. Innovative prosthodontic concepts as described should be used to enhance the biologic as well as the esthetic data of the supporting tissues, in natural teeth and implants alike. Combined dental treatment modalities of different kinds (i.e., orthodontics, periodontal treatment) are often required for optimal results. Meticulous care and attention to the delicate soft tissues should be given throughout all phases of the treatment, with a view to achieving a functional, healthy, and esthetic oral environment.

Purpose: The aim of this study was to determine effect of compressive cyclic loading on fatigue resistance and microleakage of monolithic CAD/CAM molar ceramic and composite crowns. Materials and Methods: Thirty-two extracted molars were prepared to receive ...

Degradation of silane coupling layers by water ingress in computer-aided design/computer-aided manufacturing (CAD/CAM) of resin composites has been reported qualitatively. In this study, we quantitatively evaluated how water absorption of CAD/CAM resin composites affects the silane coupling layer by in vitro and in silico methods. Methods: A Katana Avencia block (KAB) and an experimental matrix block composed of only a matrix resin were used to evaluate the effect of water immersion for seven days on the elastic modulus. X-ray photoelectron spectroscopy (XPS) with fluorine-labeling of the KAB was performed to evaluate the atomic percentage of F1s, which represents the hydrolysis amount by water immersion. In silico analysis of the three-dimensional model of the KAB was performed to determine the coupling ratios before and after water immersion. Results: The elastic modulus of the KAB was 8.2 GPa before and 6.9 GPa after immersion in water. The atomic percentages of F1s in the after-and before-immersion groups were 14.31% and 11.52%, respectively, suggesting that hydrolysis of the silane coupling layer occurred during water immersion. From in silico analysis of the three-dimensional model of the KAB, the coupling ratio was predicted to be 78.2% before water immersion. After water immersion, the coupling ratio was predicted to be 68.4%. Conclusion: The in vitro and in silico approaches established in this study were able to predict the silane coupling ratios of CAD/CAM resin composites, and they showed that the silane coupling ratio decreased by water absorption.

To evaluate the effect of an 8% arginine-calcium carbonate fluoride-free desensitizing paste on the surface roughness of resin composite, porcelain, amalgam, gold, and human dental enamel both prior to and following simulated toothbrushing. A resin composite (Filtek Supreme), a commercial porcelain (IPS Empress), an amalgam (Dispersalloy), gold (JIF-PF) and human dental enamel were used, as well as commercial finishing and polishing instruments. Eight two-sided samples were fabricated for each group. The composite and amalgam samples were stored at 100% relative humidity and 37 degrees C for 48 hours prior to measuring the surface roughness and completing the subsequent finishing and polishing procedures. Enamel blocks were cut from human lesion-free teeth and embedded in acrylic. The blocks were then polished flat with high polishing pastes. For gold and porcelain, the same size was used and the materials processed by a professional dental laboratory. Following storage, each surfac...

The aim of this study was to evaluate the clinical performance of simple fixed space maintainers bonded by using a flow composite resin (Tetric Flow) to prevent space resulting from early extracted primary teeth. For that reason, 64 fixed space maintainers (34 in the lower jaw and 30 in the upper jaw) were applied to 45 patients. The patients followed up for 12 to 18 months. Survival rate, prevention ability of that space, and whether damage to the abutment teeth occurred were evaluated. Five percent of space maintainers were determined to be unsuccessful at the end of the control period. During this period, loss of space among the abutment teeth was found to be statistically insignificant (P &gt; .05). Finally, it was observed that the use of simple fixed space maintainers was successful due to operator experience and the choosing of favorable patient groups.

To evaluate the radiopacity, ultimate tensile strength (UTS), microhardness (KHN), degree of conversion (DC), water sorption (WS) and solubility (SL) of experimental adhesives. Five experimental adhesives with different concentrations of barium-borosilicate oxide microfillers [0% (R0), 30% (R30), 40% (R40), 50% (R50), 60% (R60)] were formulated based on the adhesive system Ambar (FGM). The adhesive Adper Single Bond 2 (SB, 3M ESPE) was used as commercial reference. For the radiopacity (n = 5), KHN (n = 5), WS (n = 10), and SL (n = 10) tests, adhesive disks were constructed (5.0 mm in diameter and 1.0 mm thick), while for UTS (n = 5), hourglass-shaped specimens with a cross-sectional area of 0.8 mm2 were used. The FTIR spectra of unpolymerized and polymerized adhesives were used to determine the DC. Data were submitted to a one-way ANOVA and Tukey&#39;s test (α = 0.05). All experimental adhesives showed radiopacity similar to enamel, except those of R0 and SB. Filler addition did not...

Two commercially available dentine-adhesive systems, Tenure and Tripton, were tested in two different cavity designs by placing 132 Class V composite restorations in cervical lesions of 35 patients. In Group A, the cervical restorations were placed totally in dentine without any intentional enamel involvement. In Group B, they were placed in dentine with adjacent enamel margins bevelled and acid etched. The retention rate, the evidence of clinical microleakage, and the marginal integrity were monitored over a 2-year period. The results of this clinical investigation indicate a high failure rate when only dentinal bonding was involved. A loss rate of 30% for Tenure and 55% for Tripton was noted in Group A after 2 years of clinical service. However, both adhesive systems used in combination with micromechanical retention on the enamel border (Group B) performed extremely well with only one restoration each having debonded over the 2-year period. Identically, marginal integrity and evidence of clinical microleakage more severely deteriorated with time for the Group A restorations in comparison with their Group B counterparts. In summary, the overall results were more positive for Tenure than for Tripton. It is concluded that micromechanical retention by acid etching of the enamel margin is still indispensable for the clinical success of cervical Class V composite restorations, primarily for retention and clinical microleakage and also, but to a lesser degree, for marginal adaptation.

The purpose of this study was to compare the retention of circlet (E) clasps and back-action clasps against three abutment surface materials during long-term simulation of attachment and detachment. Forty-eight test models were constructed by placing premolars (natural abutments or metal dies) inside metal blocks to test different abutment retention surface materials (sound enamel, composite resin, and glass-ceramic; 16 each). The models were duplicated into investment models for construction of circlet (E) and back-action clasps. Removal and insertion cycling of clasps was carried out for 250, 500, 1000, 2000, 4000, 8000, and 16,000 cycles. The retention of each clasp was measured before cycling and after each interval. Data were analyzed using 1-way-ANOVA, 2-way-ANOVA, and Mann-Whitney U tests. No significant differences in retention of either clasp were found between the three abutment material surfaces; however, there was a significant decrease in retention force of the circlet (E) clasp between 1000 and 2000 cycles but not of the back-action clasp. (1) The back-action clasp maintains its retention force for a longer period than the circlet (E) clasp. (2) Composite resin contouring of teeth provided retention comparable to enamel and a ceramic material.

The aim of this study was to compare the resistance of endodontically treated teeth with intraradicular retainer different amounts of remaining coronal structure. Fifty freshly extracted maxillary canines were endodontically treated and randomly assigned to five groups (n=10), as follows: group 1 (control) = teeth with custom cast post and core; group 2 = teeth without remaining coronal structure; group 3, 4 and 5 = teeth with 1 mm, 2 mm and 3 mm of remaining coronal structure, respectively. All specimens in groups 2 to 5 were restored with prefabricated post and resin core. The teeth were embedded in acrylic resin and the fracture strength was measured on a universal testing machine at 45 degrees to the long axis of the tooth until failure. Data were analyzed statistically by one-way analysis of variance and Tukey's test. There was no significant differences (p>0.05) between the control group and group 2, and between groups 3, 4 and 5 (p>0.05). Control group and group 2 had significantly higher resistance strength than groups 3, 4 and 5 (p<0.00001). The findings of this study showed that teeth without remaining coronal structure had significantly higher fracture strength than those with remaining coronal structure (1 mm, 2 mm and 3 mm). When the dental crown was not completely removed, the amount of remaining coronal dentin did not significantly affect the fracture strength of endodontically treated teeth with intraradicular retainer.