The Photoinitiators Used in Resin Based Dental Composite—A Review and Future Perspectives

Abstract

The presented paper concerns current knowledge of commercial and alternative photoinitiator systems used in dentistry. It discusses alternative and commercial photoinitiators and focuses on mechanisms of polymerization process, in vitro measurement methods and factors influencing the degree of conversion and hardness of dental resins. PubMed, Academia.edu, Google Scholar, Elsevier, ResearchGate and Mendeley, analysis from 1985 to 2020 were searched electronically with appropriate keywords. Over 60 articles were chosen based on relevance to this review. Dental light-cured composites are the most common filling used in dentistry, but every photoinitiator system requires proper light-curing system with suitable spectrum of light. Alternation of photoinitiator might cause changing the values of biomechanical properties such as: degree of conversion, hardness, biocompatibility. This review contains comparison of biomechanical properties of dental composites including different photosensitizers among other: camphorquinone, phenanthrenequinone, benzophenone and 1-phenyl-1,2 propanedione, trimethylbenzoyl-diphenylphosphine oxide, benzoyl peroxide. The major aim of this article was to point out alternative photoinitiators which would compensate the disadvantages of camphorquinone such as: yellow staining or poor biocompatibility and also would have mechanical properties as satisfactory as camphorquinone. Research showed there is not an adequate photoinitiator which can be as sufficient as camphorquinone (CQ), but alternative photosensitizers like: benzoyl germanium or novel acylphosphine oxide photoinitiators used synergistically with CQ are able to improve aesthetic properties and degree of conversion of dental resin.

Acenaphthoquinoxaline Derivatives as Dental Photoinitiators of Acrylates Polymerization

“…However, a large amount of filler (up to 70%) limits the depth of light penetration Photoinduced radical polymerization of various monomers has been gaining more and more interest in various industries in recent decades [6,32]. Many of the developed photoinitiating systems meet the requirements for specific applications in the technology of protective coatings [33][34][35], graphics industry [36], microelectronics [37], optical disc production [38], holography [39][40][41], stereolithography [42][43][44] and medicine [45][46][47][48][49][50][51]. Photopolymerization has also become an integral part of dental practice [52].…”

“…The compound was prepared using acenaphthequinone (1.0 g, 5.5 mmol) and 4methoxy-1,2-diaminobenzene (1.15 g, 5.5 mmol) in 50…”

Viscosity, Degree of Polymerization, Water Uptake, and Water Solubility Studies on Experimental Dichloro-BisGMA-Based Dental Composites

“…Nevertheless, for both filled and unfilled dCl-BisGMA-based composites, the obtained DC was above the minimum acceptable values for clinical use (>55%) [35]. The DC of dental composite commonly varies between 40% and 75% [36]; however, other ranges were also reported [37,38] with higher values closer to 85% [39]. The difference in the DC of various systems can be due to several reasons, including the variation in composition, viscosity, curing conditions, curing times, etc.…”

Utilizing Light Cure Units: A Concise Narrative Review

“…Ivocerin is a new photo-initiator which was developed with the aim of providing a wider spectrum of short-wave absorption. It is a patented germanium derivative and is currently only used in certain Vivadent products [ 5 , 51 ]. The absorption spectrum of Ivocerin is 390–445 nm, with 415 nm being the absorbance maximum [ 52 , 53 ].…”