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The study showed an application of the 3 D Digital Image Correlation Method (3 D-DIC) for detection of von Mises strain in samples of the self-etch, self-adhesive resin based cement (RBC). The aim was to determine and compare strain in the self-cured and light-cured Maxcem Elite, furthermore to investigate the hardness of these two cement-types. The experiment was carried out using two groups of Maxcem Elite (Kerr, Orange, CA, USA) samples; each tested group includes five (o5 x 2 mm sized) samples, for both self-curing and light-curing mode. All samples were prepared by filling teflon ring-type molds. In addition, Vickers micro-hardness was measured for all samples. Maxcem Elite showed similar maximum strain values from 10% to 12% for both groups. Besides the maximum strain value, the 3 D-DIC method also enabled monitoring the change of strain field even after the recommended polymerization time. This method has shown that the polymerization shrinkage continues even after 10 min which disagreed with manufacturer's suggestion. Group II showed maximum strain values of 12% in the peripheral zone after 10 min, in the last Stage (Stage 60). Statistically significant difference was not found in the overall strain between self- and light-cured Maxcem Elite neither peripherally (p = 0.118) nor centrally (p = 0.879). However, statistical significance was found in strain regarding central and peripheral zone in both, self-cured (p = 0.020) and light-cured (p = 0.002) Maxcem Elite. The mean von Mises strain values in the periphery of the samples (Section 0) were significantly higher compared to strain values in the center of the samples (for Section 1 and 2). The last stage (Stage 60) of the light-cured Maxcem Elite polymerization showed significantly higher values of von Mises strain compared to initial stage (Stage 0). Higher values of micro-hardness were noticed on the surfaces directly exposed to LED lamp after performing measurements of micro-hardness on light-cured sampl

The study showed an application of the 3 D Digital Image Correlation Method (3 D-DIC) for detection of von Mises strain in samples of the self-etch, self-adhesive resin based cement (RBC). The aim was to determine and compare strain in the self-cured and light-cured Maxcem Elite, furthermore to investigate the hardness of these two cement-types. The experiment was carried out using two groups of Maxcem Elite (Kerr, Orange, CA, USA) samples; each tested group includes five (o5 x 2 mm sized) samples, for both self-curing and light-curing mode. All samples were prepared by filling teflon ring-type molds. In addition, Vickers micro-hardness was measured for all samples. Maxcem Elite showed similar maximum strain values from 10% to 12% for both groups. Besides the maximum strain value, the 3 D-DIC method also enabled monitoring the change of strain field even after the recommended polymerization time. This method has shown that the polymerization shrinkage continues even after 10 min which disagreed with manufacturer's suggestion. Group II showed maximum strain values of 12% in the peripheral zone after 10 min, in the last Stage (Stage 60). Statistically significant difference was not found in the overall strain between self- and light-cured Maxcem Elite neither peripherally (p = 0.118) nor centrally (p = 0.879). However, statistical significance was found in strain regarding central and peripheral zone in both, self-cured (p = 0.020) and light-cured (p = 0.002) Maxcem Elite. The mean von Mises strain values in the periphery of the samples (Section 0) were significantly higher compared to strain values in the center of the samples (for Section 1 and 2). The last stage (Stage 60) of the light-cured Maxcem Elite polymerization showed significantly higher values of von Mises strain compared to initial stage (Stage 0). Higher values of micro-hardness were noticed on the surfaces directly exposed to LED lamp after performing measurements of micro-hardness on light-cured sampl

The study showed an application of the 3 D Digital Image Correlation Method (3 D-DIC) for detection of von Mises strain in samples of the self-etch, self-adhesive resin based cement (RBC). The aim was to determine and compare strain in the self-cured and light-cured Maxcem Elite, furthermore to investigate the hardness of these two cement-types. The experiment was carried out using two groups of Maxcem Elite (Kerr, Orange, CA, USA) samples; each tested group includes five (o5 x 2 mm sized) samples, for both self-curing and light-curing mode. All samples were prepared by filling teflon ring-type molds. In addition, Vickers micro-hardness was measured for all samples. Maxcem Elite showed similar maximum strain values from 10% to 12% for both groups. Besides the maximum strain value, the 3 D-DIC method also enabled monitoring the change of strain field even after the recommended polymerization time. This method has shown that the polymerization shrinkage continues even after 10 min which disagreed with manufacturer's suggestion. Group II showed maximum strain values of 12% in the peripheral zone after 10 min, in the last Stage (Stage 60). Statistically significant difference was not found in the overall strain between self- and light-cured Maxcem Elite neither peripherally (p = 0.118) nor centrally (p = 0.879). However, statistical significance was found in strain regarding central and peripheral zone in both, self-cured (p = 0.020) and light-cured (p = 0.002) Maxcem Elite. The mean von Mises strain values in the periphery of the samples (Section 0) were significantly higher compared to strain values in the center of the samples (for Section 1 and 2). The last stage (Stage 60) of the light-cured Maxcem Elite polymerization showed significantly higher values of von Mises strain compared to initial stage (Stage 0). Higher values of micro-hardness were noticed on the surfaces directly exposed to LED lamp after performing measurements of micro-hardness on light-cured sampl

The study showed an application of the 3 D Digital Image Correlation Method (3 D-DIC) for detection of von Mises strain in samples of the self-etch, self-adhesive resin based cement (RBC). The aim was to determine and compare strain in the self-cured and light-cured Maxcem Elite, furthermore to investigate the hardness of these two cement-types. The experiment was carried out using two groups of Maxcem Elite (Kerr, Orange, CA, USA) samples; each tested group includes five (o5 x 2 mm sized) samples, for both self-curing and light-curing mode. All samples were prepared by filling teflon ring-type molds. In addition, Vickers micro-hardness was measured for all samples. Maxcem Elite showed similar maximum strain values from 10% to 12% for both groups. Besides the maximum strain value, the 3 D-DIC method also enabled monitoring the change of strain field even after the recommended polymerization time. This method has shown that the polymerization shrinkage continues even after 10 min which disagreed with manufacturer's suggestion. Group II showed maximum strain values of 12% in the peripheral zone after 10 min, in the last Stage (Stage 60). Statistically significant difference was not found in the overall strain between self- and light-cured Maxcem Elite neither peripherally (p = 0.118) nor centrally (p = 0.879). However, statistical significance was found in strain regarding central and peripheral zone in both, self-cured (p = 0.020) and light-cured (p = 0.002) Maxcem Elite. The mean von Mises strain values in the periphery of the samples (Section 0) were significantly higher compared to strain values in the center of the samples (for Section 1 and 2). The last stage (Stage 60) of the light-cured Maxcem Elite polymerization showed significantly higher values of von Mises strain compared to initial stage (Stage 0). Higher values of micro-hardness were noticed on the surfaces directly exposed to LED lamp after performing measurements of micro-hardness on light-cured sampl

Objective. The aim of this study was to evaluate the clinical effectiveness of a one-step HEMA-free self-etching adhesive (SEA) placed with a micro-fine hybrid resin composite in Class II restorations. The restorations were compared intraindividually with 2-step HEMA containing SEA-giomer restorations. Material and methods. Fifty-four patients with at least one pair of two similar Class II cavities participated (30 men, 24 women; mean age 57.1 yrs). A total of 115 Class II composite restorations were placed with (1) a one step HEMA-free adhesive and a micro-fine hybrid resin composite (Gbond/Gradia Direct: 60; GG) and (2) a 2-step HEMA-containing SEA and a giomer (FL Bond/Beautifil: SS; FB). Each participant received in a randomized way at least one restoration with each of the experimental materials. The restorations were evaluated at baseline and yearly during a 6 year followup using modified USPHS criteria. Results. During the 6 years, 111 restorations could be evaluated. No post-operative sensitivity was reported by the participants. Fourteen failed restorations (12.6%) were observed during the follow up, 5 GG (8.5%; 4 premolar and 1 molar teeth) and 9 FB (17.7%; 1 premolar and 8 molar teeth) (p <0.05). Annual failure rate at 6 years were 1.4% for GB and 3.0% for FB. Main reasons of failure were bulk fracture of resin composite for FB and tooth fracture for GB. Signcance. The HEMA-free SEA-hybrid RC restorations showed good clinical durability in Class II cavities after 6 years. The HEMA-containing SEA-giomer restorations showed a rather high failure frequency. (C) 2013 Academy of Dental Materials. Published by Elsevier Ltd. All rights reserved.

OBJECTIVE: The aim of this study was to evaluate the 5 year clinical dentin bonding effectiveness of two HEMA-free adhesives in Class V non-carious cervical lesions. MATERIAL AND METHODS: A total of 169 Class V restorations were placed in 67 patients with a self-etching adhesive (G-Bond; 67), a 3-step HEMA and TEGDMA free etch-and-rinse (cfm; 51) and a control HEMA-containing etch-and-rinse adhesive (XP Bond; 51) in non-carious cervical lesions without intentional enamel involvement. The restorations were evaluated at baseline and yearly during a 5 year follow-up with modified USPHS criteria. Dentin bonding efficiency was determined by the percentage of lost restorations. RESULTS: During the 5 years, 159 restorations could be evaluated. Good short time dentin retention was observed for the three adhesives, there all adhesives fulfilled at 18 months the full acceptance ADA criteria. At 5 years a cumulative number of 22 lost restorations (13.8%) was observed. The HEMA-free adhesives showed significantly higher dentin retention compared to the HEMA-containing one. Loss of retention was observed for 5 G-Bond (7.9%), 4cfm (8.3%) and 13 XP Bond (27.1%) restorations (p<0.05). No post-operative sensitivity was reported by the participants. No secondary caries was observed. SIGNIFICANCE: The durability in non-carious cervical lesions of the HEMA-free adhesives was successful after 5 years. Despite concerns which have been raised, showed the 1-step SEA one of the best reported clinical dentin bonding effectiveness.

Background: The aim of this study was to evaluate the influence of preliminary phosphoric acid etching on the microleakage of a self-adhering flowable composite and a self-etch adhesive used in combination with the proprietary flowable composite. Methods: Standard Class V cavities were prepared on the buccal side of 20 extracted sound human molars. Specimens were randomly divided into five groups: (1) Gel Etchant/Optibond FL/Premise Flowable; (2) Vertise Flow; (3) Optibond XTR/Premise Flowable; (4) Gel Etchant/Vertise Flow; and (5) Gel Etchant/Optibond XTR/Premise Flowable (Kerr). The interfacial sealing ability of the materials was evaluated by scoring the depth of silver nitrate penetration and through scanning electron microscopy observations. Differences in leakage at either the enamel or the dentine interface were evaluated for statistical significance (KruskalWallis ANOVA, MannWhitney U test, p lt 0.05). Results: At the enamel interface, no significant differences were found among the materials. On dentine, Gel Etchant/Vertise Flow had the highest leakage scores and the difference was statistically significant (p lt 0.05). Conclusions: The early sealing ability of the self-adhering flowable composite and the self-etch adhesive in Class V restorations did not significantly benefit from selective enamel etching. Preliminary phosphoric acid etching of dentine negatively affected the quality of the seal when using the adhesive-free flowable composite.

OBJECTIVE: The aim of this study was to evaluate the clinical retention of a one-step self-etching adhesive system (Xeno III) in Class V non-carious cervical lesions and the effect of restorative material and curing techniques on longevity of the restorations. MATERIALS AND METHODS: A total of 139 Class V restorations were placed with the self-etching primer Xeno III and a resin composite (Tetric Ceram) or a poly-acid modified resin composite (Dyract AP) in non-carious cervical lesions without intentional enamel involvement. The materials were cured with a conventional continuous light, a soft-start or a pulse-delay curing mode. The restorations were evaluated at baseline, 6, 12, 18 and 24 months and then yearly during a 7 year follow-up with modified USPHS criteria. Dentine bonding efficiency was determined by the percentage of lost restorations. RESULTS: During the 7 years, 135 restorations could be evaluated. No post-operative sensitivity was reported by the participants. Overall relative cumulative loss rate frequencies for the adhesive system at 6 and 18 months and 7 years, independent of curing technique and restorative material, were 0.8%, 6.9% and 23.0%, respectively. The self-etching adhesive fulfilled at 18 months the full acceptance ADA criteria. Tetric Ceram showed at 7 years a 20.9% loss of retention and Dyract AP a 25.0% loss rate (Log rank p=0.48). The loss rates for the 3 curing techniques: continuous, soft start and pulse delay were 17%, 27.9% and 24.4%, respectively (Log rank p=0.52). No secondary caries was observed. SIGNIFICANCE: The single-step self-etching adhesive showed acceptable clinical long-time retention rates to dentine surfaces independent of restorative material and curing technique used.

Background: The aim of this study was to evaluate the influence of preliminary phosphoric acid etching on the microleakage of a self-adhering flowable composite and a self-etch adhesive used in combination with the proprietary flowable composite. Methods: Standard Class V cavities were prepared on the buccal side of 20 extracted sound human molars. Specimens were randomly divided into five groups: (1) Gel Etchant/Optibond FL/Premise Flowable; (2) Vertise Flow; (3) Optibond XTR/Premise Flowable; (4) Gel Etchant/Vertise Flow; and (5) Gel Etchant/Optibond XTR/Premise Flowable (Kerr). The interfacial sealing ability of the materials was evaluated by scoring the depth of silver nitrate penetration and through scanning electron microscopy observations. Differences in leakage at either the enamel or the dentine interface were evaluated for statistical significance (KruskalWallis ANOVA, MannWhitney U test, p lt 0.05). Results: At the enamel interface, no significant differences were found among the materials. On dentine, Gel Etchant/Vertise Flow had the highest leakage scores and the difference was statistically significant (p lt 0.05). Conclusions: The early sealing ability of the self-adhering flowable composite and the self-etch adhesive in Class V restorations did not significantly benefit from selective enamel etching. Preliminary phosphoric acid etching of dentine negatively affected the quality of the seal when using the adhesive-free flowable composite.

OBJECTIVES: The aim of this study was to evaluate the long-term clinical retention to dentin of a two-step self-etching adhesive system Clearfil SE Bond and a two-step etch-and-rinse system PQ1. METHODS: A total of 119 Class V restorations were placed in non-carious cervical lesions without intentional involvement of the enamel incisal of the lesions. The restorations were evaluated yearly during an 8-year follow-up. Clinical dentin bonding efficiency was determined by the percentage of lost restorations at each of the recalls. RESULTS: At 8 years, 112 restorations could be evaluated. Both adhesives fulfilled the ADA 18-month full acceptance criteria for retention with a retention rate of 90.6% for PQ1 and 98.2% for Clearfil SE Bond. The loss rates increased then considerably after 2 and 3 years, respectively. The cumulative loss rates at 8 years were 25.5% for Clearfil SE and 39.3% for PQ1 (p=0.12). No significant differences were observed between lesions with sclerotic and non-sclerotic dentin. The size of the lesions did not influence the bonding effectiveness. A lower loss rate was found for the restorations placed in lesions slightly roughened before etching. CONCLUSION: Both adhesive systems showed acceptable short-term clinical retention to dentin, which decreased after long-time in vivo aging, especially for the simplified etch-and-rinse system.