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Objectives: Adhesion and marginal adaptation of a claimed bioactive restorative material (ACTIVA BioACTIVE Restorative) to human teeth were compared with those of a resin-modified glass ionomer cement (Fuji II LC) and a control resin composite (Ceram X Mono). Material and Methods: Shear bond strength and marginal adaptation to enamel and dentine were assessed after no pretreatment of the hard tissues or after etching with phosphoric acid (ACTIVA BioACTIVE Restorative and Ceram X Mono) or polyacrylic acid (Fuji II LC). For ACTIVA BioACTIVE Restorative, the effect of applying a self-etch adhesive (Xeno Select, Dentsply Sirona) was also investigated. Data were analyzed using non-parametric tests (α = 0.05). Results: Bond strength and marginal adaptation in enamel and dentine were significantly different among the investigated materials (p<.05). Due to loss of restorations, it was not possible to measure bond strength of ACTIVA BioACTIVE Restorative if no pretreatment was performed or if dentine was etched; however, use of the self-etch adhesive resulted in similar bond strength as Ceram X Mono. Etching improved adhesion of Fuji II LC to enamel and dentine. Regarding marginal adaptation, ACTIVA BioACTIVE Restorative showed the highest wall-to-wall contraction to enamel in all pretreatment groups and the overall highest wall-to-wall contraction to dentine after etching. Due to loss of restorations, no marginal assessment was possible on cavities with margins in dentine when no pretreatment was used. The use of a self-etch adhesive with ACTIVA BioACTIVE Restorative resulted in similar adaptation to dentine compared to the other materials. Conclusion: The self-adhesive property of ACTIVA BioACTIVE Restorative is nonexistent.

Objective: To systematically review the quality of evidence of available in vitro solubility studies on endodontic sealers according to prespecified evidence criteria. Material and methods: This systematic review was based on the PRISMA guidelines and the AMSTAR measurement tool. A systematic duplicate search of the literature on endodontic sealer solubility studies was conducted in PubMed and Embase databases (until 18 October 2017). Mapping terms to subject headings and free text terms were used and combined with hand searching before exclusion of duplicates. Studies specifically dealing with endodontic sealer solubility were selected. The evidence level was graded (low, medium or high) independently by two investigators following systematic data extraction in pilot forms, which was based on prespecified evidence criteria and the modified CONSORT checklist for in vitro studies on dental materials. Results: The search retrieved 1053 articles, from which 88 were assessed in full. From the 63 articles retained in the final analysis, 11 were classified as having moderate and 52 as low quality of evidence (0 high). The studies graded as low had low sample size (n < 10) and/or insufficient details to allow replicability. Most of the studies did not conform to the modified CONSORT checklist and did not include parameters considered relevant in the prespecified criteria. Conclusions: Existing in vitro studies on the solubility of endodontic sealers do not demonstrate a high quality of evidence. Most of these studies do not present systematic reporting nor employ relevant parameters prespecified in our evidence criteria.

OBJECTIVE: To investigate the relationship between physicochemical interactions of resin luting cements with dentine and retention of fibre posts in root canals.METHODS: Retention of fibre posts (RelyX Fiber Post) was assessed by the pull-out method. The diffusion zone of the cements and their chemical interaction with dentine were estimated by micro-Raman spectroscopy. Resin luting cements employing etch-and-rinse (Rely X Ultimate and Variolink II), self-etch (Rely X Ultimate and Panavia F2.0), or self-adhesive (RelyX Unicem 2) modes were investigated. Data were analyzed by analysis of variance followed by Tukey HSD tests.RESULTS: The retention of the fibre posts decreased in the following order: RelyX Ultimate, etch-and-rinse mode>RelyX Unicem 2≥RelyX Ultimate, self-etch mode≥Panavia F2.0≥Variolink II (p<0.05). One of the etch-and-rinse mode cements presented the deepest diffusion zone, while the other, along with the self-adhesive cement, produced the shallowest zone. Cements used in the self-etch mode showed intermediary diffusion into dentine (p<0.05). All resin luting cements showed some degree of chemical interaction with dentine, the highest recorded for RelyX Ultimate used in the etch-and-rinse mode and the lowest for Panavia F2.0 (p<0.05). The retention of fibre posts in the root canal could be attributed neither to the mode of interaction of the luting cements with dentine nor to their ability to diffuse into dentine.SIGNIFICANCE: Chemical interaction between the resin luting cement and the dentine paired with adequate post pretreatment contribute positively to the retention of fibre posts.

I denne artikel gennemgås litteraturen med særligt fokus på ydeevnen af de bindingssystemer, som anvendes i dag. I PubMed-databasen søgtes efter emneordene ”dental adhesive” og publikationer fra de sidste fem år blev prioriteret. Så vidt muligt fokuseredes på meta-analyser af de begrænsede kliniske data, således at retentionsevnen for etch & rinse, selvætsende og universelle bindingssystemer kan ses uafhængigt af forskningsgrupper eller behandlere. Relevante reviews og nyere kliniske undersøgelser blev ligeledes inkluderet. Den foreliggende evidens for de tre typer af bindingssystemer præsenteres og diskuteres. Etch & rinse og selvætsende bindingssystemer har været længst på markedet, og for nogle af disse systemer viser kliniske data god retentionsevne. Da de universelle bindingssystemer er relativt nye, er kliniske studier med længere opfølgningstid begrænsede. De få eksisterende studier har givet lovende resultater, og det ser ud som om, at disse adhæsiver er vejen frem., This article presents a review of the literature with special focus on the performance of the dental bonding agents that are used today. The database PubMed was searched using the terms “dental adhesive” and among the selected articles priority was given to publications from the last five years. The collection of clinical data in the form of meta-analyses was included, thereby allowing the bonding properties of etch & rinse, self-etch and universal adhesives to be examined independently of the research group or the clinician performing the bonding. Relevant reviews and recent clinical trials were also considered. The existing evidence is presented and discussed for the three types of bonding agents. Etch & rinse and self-etch systems have been on the market for a longer period of time, hence their bonding properties can be confirmed by clinical data. Since the universal adhesives are relatively new, only a limited number of clinical studies with longer evaluation periods are available at this time. So far, the universal adhesives show good potential and seem to be the way forward in adhesive dentistry.

The aim of this study was to investigate the effect of the cement film thickness of a zinc phosphate or a resin cement on retention of untreated and pretreated root canal posts. Prefabricated zirconia posts (CosmoPost: 1.4 mm) and two types of luting cements (a zinc phosphate cement [DeTrey Zinc] and a self-etch adhesive resin cement [Panavia F2.0]) were used. After removal of the crowns of 360 extracted premolars, canines, or incisors, the root canals were prepared with a parallel-sided drill system to three different final diameters. Half the posts did not receive any pretreatment. The other half received tribochemical silicate coating according to the manufacturer's instructions. Posts were then luted in the prepared root canals (n=30 per group). Following water storage at 37°C for seven days, retention of the posts was determined by the pull-out method. Irrespective of the luting cement, pretreatment with tribochemical silicate coating significantly increased retention of the posts. Increased cement film thickness resulted in decreased retention of untreated posts and of pretreated posts luted with zinc phosphate cement. Increased cement film thickness had no influence on retention of pretreated posts luted with resin cement. Thus, retention of the posts was influenced by the type of luting cement, by the cement film thickness, and by the post pretreatment.

The development of dental materials with improved properties and increased longevity can save costs and minimize discomfort for patients. Due to their good biocompatibility, glass ionomer cements are an interesting restorative option. However, these cements have limited mechanical strength to survive in the challenging oral environment. Therefore, a better understanding of the structure and hydration process of these cements can bring the necessary understanding to further developments. Neutrons and X-rays have been used to investigate the highly complex pore structure, as well as to assess the hydrogen mobility within these cements. Our findings suggest that the lower mechanical strength in glass ionomer cements results not only from the presence of pores, but also from the increased hydrogen mobility within the material. The relationship between microstructure, hydrogen mobility and strength brings insights into the material's durability, also demonstrating the need and opening the possibility for further research in these dental cements.

Glass Ionomer Cement (GIC) bliver brugt i tandplejen som et genopbyggende materiale pga. dets klæbeevne til tandoverfladen, god biokompatibilitet og dets evne til at frigive fluorid. GICs mekaniske egenskaber gør, at det er uegnet i områder med stor belastning, som fx ved store karies i molar om- rådet. Derfor er målet med dette speciale at modificere en kommerciel GIC (Voco Ionofil Molar AC) med en forhåbning om at forbedre de mekaniske og fysiske egenskaber ved materialet. Ideen har her været at erstatte en del af glas-partiklerne med hydroxyapatit i forskellige partikel størrelser og i forskellige koncentrationer. De brugte testmetoder til evalueringen af de eksperimentielle materialer er Compressive Fracture Strength (CFS), Ther- mogravimetric analysis (TGA) og røntgentomografi. Resultaterne fra CFS- testen indikerer, at en 1wt% erstatning er det eksperimentielle materiale, der giver de bedste resultater. Udover dette ser det ud til, at partikelstørrelsen påvirker styrken. Resultaterne indikerer også, at hydroxyapatit-modificeret GIC opnår hurtigere styrke end den kommercielle GIC., Glass ionomer cement (GIC) is used in dentistry as a restorative material due to its adhesion to tooth surfaces, good biocompatibility and its ability to release fluoride. However the mechanical properties make it undesirable for use in load bearing areas, such as large cavities in the molar region. There- fore the aim of this work was to modify a commercial GIC (Voco Ionofil Molar AC) hoping to improve the mechanical and physical properties of this material. The idea was to substitute part of the glass particles with hydrox- yapatite of different particle sizes using different concentrations. The testing methods used to evaluate the properties of the experimental materials were Compressive Fracture Strength (CFS), Thermogravimetric analysis (TGA) and X-ray Tomography. The results from the CFS tests seem to indicate that a 1wt% substitution is the most desirable. Moreover particle size ap- pears to influence the strength. The results also seem to indicate that the hydroxyapatite-modified GIC reaches early strength faster than the commer- cial GIC.

SUMMARY The bulk-filling of deep, wide dental cavities is faster and easier than traditional incremental restoration. However, the extent of cure at the bottom of the restoration should be carefully examined in combination with the polymerization contraction and gap formation that occur during the restorative procedure. The aim of this study, therefore, was to compare the depth of cure, polymerization contraction, and gap formation in bulk-fill resin composites with those of a conventional resin composite. To achieve this, the depth of cure was assessed in accordance with the International Organization for Standardization 4049 standard, and the polymerization contraction was determined using the bonded-disc method. The gap formation was measured at the dentin margin of Class II cavities. Five bulk-fill resin composites were investigated: two high-viscosity (Tetric EvoCeram Bulk Fill, SonicFill) and three low-viscosity (x-tra base, Venus Bulk Fill, SDR) materials. Compared with the conventional resin composite, the high-viscosity bulk-fill materials exhibited only a small increase (but significant for Tetric EvoCeram Bulk Fill) in depth of cure and polymerization contraction, whereas the low-viscosity bulk-fill materials produced a significantly larger depth of cure and polymerization contraction. Although most of the bulk-fill materials exhibited a gap formation similar to that of the conventional resin composite, two of the low-viscosity bulk-fill resin composites, x-tra base and Venus Bulk Fill, produced larger gaps.

OBJECTIVE: To investigate how the modulus of elasticity of resin composites influences marginal quality in restorations submitted to thermocyclic and mechanical loading.METHODS: Charisma, Filtek Supreme XTE and Grandio were selected as they were found to possess different moduli of elasticity but quite similar polymerization contraction. MOD cavities (n=30) were prepared in extracted premolars, restored and then subjected to thermocyclic and mechanical loading. Marginal quality of the restorations before and after loading was analyzed on epoxy replicas under a scanning electron microscope. The percentage of gap-free margins and occurrence of paramarginal fractures were registered. Modulus of elasticity and polymerization contraction were analyzed with parametric and margins with nonparametric ANOVA and post hoc Tukey HSD or Wilcoxon rank-sum tests, respectively. The number of paramarginal fractures was analyzed with exact Fisher tests (α=0.05).RESULTS: Grandio demonstrated significantly more gap-free enamel margins than Charisma and Filtek Supreme XTE, before and after loading (p<0.01), whereas there was no difference between Charisma and Filtek Supreme XTE (p>0.05). No significant effect of resin composite (p=0.81) on the quality of dentine margins was observed, before or after loading. Deterioration of all margins was evident after loading (p<0.0001). More paramarginal enamel fractures were observed after loading in teeth restored with Grandio when compared to Charisma (p=0.008).CONCLUSIONS: The resin composite with the highest modulus of elasticity resulted in the highest number of gap-free enamel margins but with an increased incidence of paramarginal enamel fractures.CLINICAL SIGNIFICANCE: The results from this study suggest that the marginal quality of restorations can be improved by the selection of a resin composite with modulus of elasticity close to that of dentine, although an increase in paramarginal enamel fractur