title: A review of the development of radical photopolymerization initiators used for designing light-curing dental adhesives and resin composites.
abstract: This paper reviews our recent studies on radical photopolymerization initiators, which are used in the design of light-curing dental adhesives and resin composites, by collating information of related studies from original scientific papers, reviews, and patent literature. The photopolymerization reactivities of acylphosphine oxide (APO) and bisacylphosphine oxide (BAPO) derivatives, and D,L-camphorquinone (CQ)/tertiary amine were investigated, and no significant differences in degree of conversion (DC) were found between BAPO and CQ/amine system (p>0.05). In addition, a novel 7,7-dimethyl-2,3-dioxobicyclo[2.2.1]heptane-1-carbonyldiphenyl phosphine oxide (DOHC-DPPO=CQ-APO) was synthesized and its ultraviolet and visible (UV-VIS) spectral behavior was investigated. CQ-APO possessed two maximum absorption wavelengths (λmax) at 350-500 nm [372 nm (from APO group) and 475 nm (from CQ moiety)], and CQ-APO-containing resins exhibited good photopolymerization reactivity, excellent color tone, relaxed operation time, and high mechanical strength. It was also found that a newly synthesized, water-soluble photoinitiator (APO-Na) improved adhesion to ground dentin.
authors.affiliation: Department of Research and Development, Shofu Inc., 11 Kamitakamatsu-cho, Fukuine, Higashiyama-ku, Kyoto 605-0983, Japan. k-ikemura@shofu.co.jp
authors.forename: Kunio
authors.initials: K
authors.lastname: Ikemura
authors.forename: Takeshi
authors.initials: T
authors.lastname: Endo
mesh_terms: D000588:Amines / Q000737:chemistry; D002164:Camphor / Q000031:analogs & derivatives / Q000737:chemistry; D003188:Composite Resins / Q000138:chemical synthesis / Q000737:chemistry*; D055117:Curing Lights, Dental; D003738:Dental Cements / Q000138:chemical synthesis / Q000737:chemistry*; D003764:Dental Materials / Q000138:chemical synthesis / Q000737:chemistry*; D006801:Humans; D008027:Light; D010720:Phosphines / Q000737:chemistry; D055668:Photochemical Processes; D058567:Photoinitiators, Dental / Q000737:chemistry*; D058105:Polymerization / Q000528:radiation effects; D013053:Spectrophotometry; D013056:Spectrophotometry, Ultraviolet
chemical_list: D000588:Amines; D003188:Composite Resins; D003738:Dental Cements; D003764:Dental Materials; D010720:Phosphines; D058567:Photoinitiators, Dental; D002164:Camphor; C553149:camphorquinone