Objectives To evaluate the surface roughness and gloss of three nanohybrid resin composites after polishing with three different polishing systems. Materials and Methods A total number of 112 disc specimens (10 × 3 mm) were prepared from nanohybrid—Empress Direct (ID), Grandio (GR), Filtek Z550 (ZN) and a microhybrid resin composite restorative materials—Filtek Z250 (ZM). Following 24-hour storage in 37°C distilled water, each composite group (n = 28) was assigned into four groups (n = 7) according to finishing/polishing (F/P) system: Mylar strip, Optrapol, Politip, and Sof-Lex (SL). The surface roughness (Ra, mm) was measured by a novel three-dimensional method using an image analysis software attached to an environmental scanning electron microscope. A glossometer was used to measure the surface gloss. Results Statistical analysis used was ANOVA test. Two-way Anova test revealed that the “type of composite” and “F/P techniques” had a significant effect on both surface roughness and gloss of the tested resin composite materials (p < 0.05). Tukey’s post hoc test showed that ID, GR, and ZN revealed lower surface roughness and higher surface gloss than ZM within the same polishing system (p < 0.05). Sof-Lex polishing discs produced the lowest surface roughness and highest surface gloss values compared with Optrapol and Politip (p < 0.05). Conclusion The tested F/P systems provided comparable surface roughness and gloss for nanohybrid composites. The Sof-Lex system provided the best surface roughness and gloss for nanohybrid composites.

Objectives In the clinical medicine, immunosuppressive drugs are used for an assortment of disorders, while their effect on the pulp healing is a controversial issue. This study evaluated the effect of different immunosuppressive drugs on the healing capacity of mechanically exposed dogs' dental pulps after direct pulp capping (DPC) with calcium silicate-based cement. Materials and methods Twelve healthy male dogs were randomly allocated into four equal groups, 3 dogs each: group I allocated as a control group where no drugs were received; group П given prednisone (Pred); group III given a combination of Pred and cyclosporine A (CsA); and group IV given triple dose including Pred, CsA, and mycophenolate mofetil (MMF) for 45 days before the operative procedures and until the dogs were euthanized. In each dog, 16 class V cavities were prepared on the labial surfaces of anterior teeth. Following mechanical exposure, the pulps were capped with Biodentine, calcium silicate-based cement. The pulpal tissues response to Biodentine was assessed 65 days postoperatively. ResultsThe pulp healing response was inferior in the Pred-CsA-and Pred-CsA-MMF-treated groups compared with the control and Pred-treated groups (P < 0.05). Non-significant difference was found between control and Pred-treated groups (P > 0.05). Conclusions Within the limitation of this study, DPC with calcium silicate-based cement performed under strict aseptic condition for traumatically exposed dental pulp can be considered as a successful treatment option for those who receiving Pred immunosuppressive therapy. Meanwhile, DPC with those receiving a combination of Pred, CsA, and/or MMF immunosuppressive drug regimens demonstrated unfavorable results. Clinical relevance Direct capping of mechanically exposed pulps with calcium silicate-based cement performed with special care for preventing infection considered a suitable strategic measure for preserving pulp vitality in patients receiving corticosteroid immunosuppressive drug.

Background Corticosteroids are commonly used as a treatment for a variety of pathological conditions, however, systemic corticosteroid administration has adverse effects including impaired immune response and wound healing. Such complications may affect pulp healing after direct pulp capping. The current study evaluated the influence of corticosteroids on the healing ability of exposed dogs’ dental pulps after direct pulp capping (DPC) with bioactive materials. Methods Ten healthy male dogs were assigned randomly into two groups, 5 dogs each: group I represent the control group which did not receive any medication, and group II was given corticosteroid for 45 days before DPC and till the dogs were euthanized (n = 75 teeth for each group). Following mechanical exposure, the pulps were randomly capped with either Ca(OH)2, MTA, or Biodentine. The pulpal tissues’ reaction to the capping materials was evaluated 65 days postoperatively according to the following parameters: calcific bridge formation, pulpal inflammation, pulp necrosis, and bacterial infiltration. Results The corticosteroid-treated group revealed no significant difference compared to the control group concerning the pulp healing response (P > 0.05). Both Biodentine and MTA-treated specimens revealed significant differences with Ca(OH)2-treated specimens (P < 0.05) which displayed a superior positive effect of both MTA and Biodentine to Ca(OH)2 regarding all the parameters. Conclusions Direct pulp capping technique whenever indicated in subjects treated with corticosteroid immunosuppressive drugs like prednisone performed well in aseptic conditions especially when capped with bioactive materials.