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Additive manufacturing is an emerging technology that has been successfully used in dentistry for denture fabrication. However, the conventional issue of tooth debonding exists in additively manufactured dentures. In this study, we investigated the physical properties of conventional teeth attached to a heat-cured denture base material compared to additively manufactured tooth-coloured materials attached to denture base-coloured materials in a printed monolithic unit. We designed a model consisting of a tooth attached to a cylindrical base to fabricate the additively manufactured group and the conventional group. All groups were tested for fracture load before and after thermocycling, water sorption, solubility, and shape accuracy. The Mann-Whitney U test was used for statistical analysis. The fracture load of the additively manufactured group was significantly higher than that of the conventional group after thermocycling ( p = 0.019). The water sorption of the conventional group was significantly lower than that of the additively manufactured group ( p = 0.000), whereas there was no significant difference in the water solubility between them ( p = 0.192). The shape accuracy of the additively manufactured group was significantly better than that of the conventional group ( p < 0.05). In conclusion, additive monolithic manufacturing technology may provide an alternative way to enhance the fracture load between the teeth and denture bases.

Nickel-catalyzed three-component coupling of bis-1,3-dienes, aldehyde, and dimethylzinc was investigated. In the presence of catalytic amounts of Ni(acac)2 and PPh3, bis-1,3-dienes smoothly react with an aldehyde and dimethylzinc via intramolecular cyclodimerization of bis-1,3-diene moiety. The reaction proceeds through formation of a cyclic bis-allylnickel complex, insertion of an aldehyde, and addition of dimethylzinc to the resulting oxanickellacycle intermediate. An enantioselective coupling was also achieved by the use of a chiral monodentate phosphine ligand, H-MOP.

The effects of ingredients of Shi-Quan-Da-Bu-Tang (Juzen-taiho-to) on the nephrotoxicity and bone marrow toxicity caused by i.p. administration of 3 mg/kg cis-diamminedichloroplatinum (II) (CDDP) 9 times (on days 3, 4, 5, 6, 7, 8, 10, 11, 12) were examined in ddY mice s.c. inoculated with sarcoma 180 (S-180) cells on day 1. Angelicae Radix showed the strongest protective effect against the toxicity among the ingredients. The ED50 of a water extract of Angelicae Radix was 17.8 mg/kg for nephrotoxicity (indicated by an increase in blood urea nitrogen) and 59.4 mg/kg for bone marrow toxicity (indicated by a decrease in white blood cell count), when it was administered perorally (p.o.) on days, 3, 4, 5, 6, 7, 8, 10, 11, 12, 13, 14, 15. The water extract did not exert any significant effect on the antitumor activity of CDDP. Bioassay-directed fractionation of the water extract resulted in isolation of a constituent having protective effects against the toxicity: sodium L-malate, C4H4Na2O5, was found to exhibit protective effects against both nephrotoxicity (ED50: 0.4 mg/kg, p.o.) and bone marrow toxicity (ED50: 1.8 mg/kg, p.o.), without reducing the antitumor activity of CDDP. These findings indicate that Angelicae Radix and its constituent sodium L-malate could provide significant protection against CDDP-induced nephrotoxicity and bone marrow toxicity without reducing the antitumor activity.