Search

To investigate the effects of dentin decontamination procedures with ethylenediaminetetraacetic acid (EDTA) after contamination with two hemostatic agents, ViscoStat (VS) and ViscoStat Clear (VSC), on the microtensile bond strength (μTBS) of two different universal adhesives, before and after thermocycling (TC).Dentin surfaces of 100 human caries-free molars were either contaminated with one of the hemostatic agents or contaminated and then decontaminated with EDTA before the universal adhesives Scotchbond Universal Adhesive (SBU) or PrimeBond Active (PBA) were applied in self-etch mode. Composite buildups were made and the teeth were sectioned into sticks (n = 90). Half of them immediately underwent the μTBS test, the other half after aging via TC. The data were statistically analyzed using Welch's ANOVA and the Games-Howell post-hoc test (p0.05).Significant differences were observed between the groups (p0.001). When the dentin surface was contaminated with VSC, TC significantly reduced the mean bond strength, regardless of the universal adhesive. Decontamination with EDTA showed a significant decrease in bond strength after VS contamination and SBU application. The fracture analysis showed mainly adhesive fractures (78.8%) in all test groups.As EDTA application did not significantly increase the μTBS of either universal adhesive in self-etch mode in-vitro, it cannot be recommended as a decontaminant.

The purpose of this in‐vivo study was to evaluate the clinical performance of restorations placed in non‐carious cervical lesions (NCCLs), using different cavity preparation designs, after 7.7 years. A total of 85 NCCLs with coronal margins in enamel and cervical margins in dentin were randomly assigned to the following treatment protocols: dentin surface cleaning, dentin surface roughening with round bur plus flowable composite, dentin surface roughening/cervical groove preparation with round bur, dentin surface roughening/cervical groove preparation with round bur plus flowable composite. After enamel beveling and selective enamel etching, the defects were restored with composite. The restorations were assessed by two independent, calibrated and blinded investigators, using modified USPHS criteria. At 7 years (7.7 (± 0.35)), a total of 64 restorations (75.3%) were available for follow‐up examination. The total retention rate, irrespective of the test groups, was 82.8%. Restorations placed without any preparation showed the highest loss rate (27.8%). Esthetic appearance, marginal adaptation, anatomic form and marginal discoloration did not differ significantly between the groups. Composites are long‐term stable materials for restoring NCCLs. Restorations placed without any dentin preparation (cavity cleaning only) showed the highest loss rate.

The pretreatment of glass-ceramic before adhesive cementation can be performed with hydrofluoric acid (HF)/silanization (S) or with an ammonium polyfluoride-containing primer (APF). It can be modified by application of a silane-containing universal adhesive (UA) and/or additional silanization. The aim of this study was to evaluate the bond strength of composite cements to two different glass ceramics after different pretreatments and aging.Disks of leucite-reinforced glass-ceramic or lithium-disilicate glass-ceramic were pretreated with HF+S, HF+UA, HF+S+UA, APF, or APF+S, bonded in pairs with composite cement and sectioned into microsticks (n = 96/group). The microtensile bond strength was determined either after 24 h (n = 48) or after aging for 6 months in water (n = 48). Fracture patterns were analyzed at 50X magnification. Statistical evaluation was performed using the Kruskal-Wallis test, pairwise comparisons with Bonferroni's correction, and the chi-squared test (p0.05).Pretreatment with HF+UA or APF led to significantly lower bond strength compared to HF+S. Additional silanization after application of UA or APF resulted in a significant increase in bond strength. After aging, HF+UA groups showed significantly lower bond strengths, independent of additive silanization. Aging did not affect APF-pretreated leucite-reinforced glass-ceramic; for lithium-disilicate glass-ceramic, the bond strength dropped significantly. Additional silanization improved aging resistance for the respective groups.Bond strength and its long-term stability depend on the ceramic used and on the pretreatment. An ammonium polyfluoride-containing primer seems to be a promising option compared to conventional pretreatment with hydrofluoric acid. Additive silanization improves the long-term stability of the microtensile bond strength.

The purpose of this in vitro study was to compare the shear bond strength of different universal adhesives to enamel and dentin with and without additional phosphoric acid etching before and after thermocycling (TC).The mesial, distal, lingual, and buccal surfaces of the teeth were ground flat to expose two enamel areas and two dentin areas. Specimens were randomly divided into 36 groups (n = 10). Four adhesives were tested: Scotchbond Universal (SBU), PrimeBond Elect (PBE), All-Bond Universal (ABU), and iBond Universal (IBU). The application was performed in the self-etch mode (SE) or in the etch-and-rinse mode (ER). Optibond FL (OFL) was used as an etch-and-rinse control. After composite buildups were made, half of the groups were tested before and the other half after TC. The failure mode was evaluated using a light microscope.In enamel, mean bond strengths ranged from 13.4 to 21.9 MPa in the SE mode before TC. When used as an ER adhesive, mean bond strengths exceeded 30 MPa. TC did not influence the mean bond strengths in either application mode. Regarding dentin, significant differences in the SE mode were adhesive dependent. Differences were only detected between SBU and IBU before TC and were not present after TC. When SBU, PBE, and ABU were used as ER adhesives, no differences were detected before TC. TC only affected IBU when compared to the other adhesives.Universal adhesives benefit from phosphoric acid etching, as bond strengths increased especially at enamel surfaces.

The aim of this study was the evaluation of microleakage in class V cavities using micro-CT imaging and dye penetration. Sixty class V cavities were prepared, randomly divided into five groups (Adper Single Bond Plus (ASB), ExciTE (EX), iBond TE (ITE), Optibond Solo Plus (OSP), Prime & Bond NT (PB)) and restored with Venus Diamond. After thermocycling and dye penetration test with 50 wt% ammoniacal silver nitrate, eight samples per group were sectioned longitudinally and evaluated under a coaxial incident light microscope (enamel (E) and dentin (D) measurement in mm). The remaining samples were analyzed by counting voids in the coronal and cervical adhesive areas by means of micro-CT. In dentin, no statistically significant difference in dye penetration was found. In enamel, OSP showed significant higher microleakage than all other adhesives (p

Das Bleichen von Zahnen stellt heute einen wichtigen Teil der asthetischen Zahnheilkunde dar. Bereits vor 150 Jahren wurden die ersten Bleichvorgehen dokumentiert. Im Allgemeinen muss unterschieden werden, ob es sich um das Bleichen eines oder mehrerer pulpaavitaler Zahne (internes Bleichen), um das Bleichen vitaler Zahne (externes Bleichen) oder eine Kombination beider Verfahren handelt. Zudem sind die Ursachen der Zahnverfarbungen sehr vielfaltig und sollten in jedem Fall eruiert werden, um die verschiedenen moglichen Therapieverfahren abzuwagen. Eine Information des Patienten ist dabei sehr wichtig und sollte ebenfalls potenzielle Nebenwirkungen und Komplikationen beinhalten.

Aim of the study was the investigation of the repairability of a silorane (Filtek Silorane, 3M Espe, Seefeld, Germany) after different surface pretreatments in vitro.54 silorane specimens (5 mm × 5 mm × 5 mm) were fabricated and stored in saline solution (24 h/37°C). Their surface was polished with abrasive paper (600 grit), etched with phosphoric acid (10 s) and rinsed with water (30 s). Repair was performed with a silorane based on one of the 9 treatment protocols (each n=6): no additional treatment (NAT), silorane primer (P) and silorane bond (B), B only, sandblasting (SB), SB plus P/B, SB plus B, CoJet and silane (CJ), CJ plus P/B, CJ plus B. Whole silorane specimens (5 mm × 5 mm × 10 mm) with no repair served as control. Specimens were sectioned and microtensile bond strength (μTBS) was measured (30 beams per group, surface area approx. 1.2 mm², crosshead-speed 1 mm/min) statistical analysis (ANOVA, Tukey HSD, p0.05) was performed.μTBS of the specimens was significantly influenced by the surface pretreatment (p0.001). The highest μTBS was determined for CJ/B and SB/B, which were not significantly different from the control. NAT, SB and CJ benefited from an additional treatment with B (p0.01). The additional use of P did not improve μTBS, but was detrimental for the SB and CJ groups (p0.05).Siloranes can be repaired with either SB or CJ in combination with a silorane bond, the additional use of silorane primer is disadvantageous.