Spectrophotometric Analysis of Different Flowable Restorative Materials.

AIM: To compare the color change of three flowable composites after exposure to staining solutions. MATERIALS AND METHODS: A total of 240 oval samples were constructed of conventional flowable resin composite, self-adhesive flowable resin composite, and nanohybrid flowable ormocer (n = 80). Each set was further subcategorized into three subsets as regards staining solution. The baseline color parameters were recorded using spectrophotometer after the immersion of the specimens in artificial saliva for 24 hours. Then, the measurements were taken again after exposure to staining solutions where the color change was measured as ΔE* = V (ΔL*2 + Δa*2 + Δb*2). RESULTS: Conventional flowable resin composite had the best color stability in all staining solutions. The coffee was concluded to be the most staining solution. Compared to beverages, mouthwashes had a greater discoloration effect on nanohybrid flowable ormocer than on selfadhesive flowable composite. CONCLUSION: Conventional flowable composite had the highest color stability among the tested materials, followed by flowable nanohybrid ormocer, and the least was self-adhering flowable composite. Coffee had the greatest discoloration effect, followed by a sports drink and then the energy drink. However, mouthwashes did not have a significant discoloration effect. CLINICAL SIGNIFICANCE: Selection of flowable composite materials that are resistant to staining by coffee, beverages, or mouthwashes is an important factor that may influence the sustainability of the esthetic quality of the restoration.

Performance of Self-adhering Flowable Composite in Class V Restorations: 18 Months Clinical Study.

AIM: The present randomized clinical study compared the 18 months performance of self-adhering flowable composite with a conventional flowable composite in anterior Class V restorations. MATERIALS AND METHODS: Totally, 20 patients, each with two moderate cervical carious lesions, participated in this single-center study. Forty restorations were allocated on a random basis by one examiner not involved in the restoration or the evaluation procedures, In each patient, one lesion was allocated to be restored using self-adhering flowable composite [Fusio liquid dentin (FL)] and the other to be restored using conventional flowable composite [Tetric Flow (FF)]. The allocation sequence of the restorations was concealed from the operator in sequentially numbered, opaque, sealed, and stapled envelopes. An operator restored all the preparations in accordance to the manufacturer's instructions. Finishing and polishing of the restorations were done immediately after placement. Evaluation of the restorations was done in accordance to the United States Public Health Services (USPHS), modified Ryge criteria. Statistical analysis was completed with Statistical Package for the Social Sciences (SPSS) version 20.0 (IBM Product, Chicago, USA). RESULTS: One case could not be reassessed at 18 months follow-up in both groups. No significant differences were detected between the tested materials from baseline to those of 18 months using the modified USPHS criteria. CONCLUSION: Self-adhering flowable composite exhibited acceptable clinical performance comparable with the conventional flow-able composite in anterior Class V restorations over an 18-month period. Nevertheless, the findings of this study must be validated by a longer clinical study. CLINICAL SIGNIFICANCE: Self-adhering flowable composite exhibited clinical performance comparable with the conventional flowable composite in Class V restoration.

Apoptotic effect of different self-etch dental adhesives on odontoblasts in cell cultures.

OBJECTIVES: We aimed to evaluate the potential cytotoxicity (apoptosis-induction) of three types of self-etch dental adhesives: two-component one-step (Xeno III), two-component two-steps (Clearfil Protect Bond) and one-component one-step (Xeno V) on cultured odontoblasts. METHODS: Each adhesive was prepared to simulate its clinical manipulation. Cured sterile individual masses were immersed in DMEM and left at 37 °C for 24 h. Then a volume of 100 µL of the extract medium was added to the cultured odontoblasts and incubated for additional 24 h, 48 h and 72 h, respectively. Acridine orange-propidium iodide (AO-PI) labelling was employed to assess the proportion of dead to total number of cells. In addition, an in situ apoptosis detection kit was used to evaluate the DNA cleavage and chromatin condensation employing the immunohistochemical (IHC) technique. Statistical analysis of the data was performed using one-way ANOVA. RESULTS: Both apoptosis evaluation methods revealed comparable results with the exception that IHC showed 5-7% less number of dead cells when compared to similar groups evaluated by AO-PI. The percentages of dead to total cells after treatment with Clearfil Protect Bond, Xeno III and Xeno V, were significantly different from the percentage of dead cells after treatment with DMEM alone (-ve control), P value <0.05 and Xeno V dental adhesive had the weakest cytotoxic effect on odontoblasts followed by Xeno III especially after 24 h of incubation. Clearfil Protect Bond had the strongest cytotoxic effect on odontoblasts that was almost closer to that of Staurosporine in DMEM (+ve control). CONCLUSION: All tested dental adhesives had remarkable adverse effect on the odontoblasts in vitro; this might be of concern when applied clinically in deep cavities where such cytotoxic chemicals become in close contact to dental pulp. Therefore, further in vivo studies on animal models are recommended to support or refute these in vitro findings.