Analysis of Photo-initiators in Visible-light-cured Dental Composite Resins

Abstract

Seven commercial visible-light-cured (VL) dental composite resins were analytically studied for identification of the photo-initiator consisting of photo-sensitizer and reducing agent. Gas-liquid chromatography (GC) was used for the determination of the dilute components extracted from the composite resin. Mass spectroscopy (GC-MS) was used for confirmation of the qualitative data obtained by GC.

The results showed that all composite resins examined included camphorquinone (CQ) as a photo-sensitizer. The concentration of CQ in the resin phase, however, ranged from 0.17 to 1.03% w/w. The composite resin with hybrid-sized filler tended to have a higher concentration of CQ than did the micro-filled composite resin.

As for the reducing agent, two out of seven brands contained dimethylaminoethyl methacrylate (DMAEMA), and one included dimethyl-p-toluidine (DMPTI). The mixing ratio between CQ and the amine in these three composite resins also varied. Another four brands did not contain either DMAEMA or DMPTI, and would utilize different reducing agents.

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References

Antonucci, J.M. ; Grams, C.L. ; and Termini, D.J. (1979): New Initiator Systems for Dental Resins Based on Ascorbic Acid, J Dent Res 58:1887-1899.

Antonucci, J.M. ; Peckoo, R.J. ; Schruhl, C. ; and Toth, E.E. (1981): Slow-acting Amine Polymerization Accelerators Paradimethylaminobenzoic Acid and Its Ethyl Ester, J Dent Res 60:1325-1331.

Bailey, E. ; Farmer, P.B. ; and Peal, J.A. (1987): Analytical Methodology to Determine Stable Isotopically Labelled and Unlabelled Theophylline in Human Plasma Using Capillary Gas Chromatography-Mass Spectrometry, J Chromatogr Biomed Appl 416:81-89.

Bowen, R.L. and Argentar, H. (1972): Tertiary Aromatic Amine Accelerators with Molecular Weights above 400, J Dent Res 51:473-482.

Brauer, G.M. ; Dulik, D.M. ; Antonucci, J.M. ; Termini, D.J. ; and Argentar, H. (1979): New Amine Accelerators for Composite Restorative Resins, J Dent Res 58:1994-2000.

Brauer, G.M. ; Stansbury, J.M. ; and Antonucci, J.M. (1981): 4 N,N-Dialkylaminophenethanols,-Alkanoic Acids and Esters: New Accelerators for Dental Composites , J Dent Res 60:1343-1348.

Cook, W.D. (1982): Spectral Distributions of Dental Photopolymerization Sources, J Dent Res 61:1436-1438.

Craig, R.G. (1981): Chemistry, Composition and Properties of Composite Resins: Symposium on Composite Resins in Dentistry, Dent Clin N Am 25:219-239.

Craig, R.G. (1985): Direct Esthetic Restorative Materials. In: Restorative Dental Materials, 7th ed., R.G. Craig , Ed., St. Louis: C.V. Mosby Co., pp. 225-246.

10.

Eliades, G.C. ; Vougiouklakis, G.J. ; and Caputo, A.A. (1987): Degree of Double Bond Conversion in Light-cured Composites, Dent Mater 3:19-25.

11.

EPA / NIH ( 1980): Mass Spectral Data Base, Supplement 1, U.S. Department of Commerce/NBS, Washington, DC.

12.

Eriksen, H.M. (1974): Pulpal Response of Monkeys to a Composite Resin Cement, J Dent Res 53:565-570.

13.

Fujisawa, S. ; Kadoma, Y. ; and Masuhara, E. (1986): Effect of Photoinitiators for the Visible-light Resin System on Hemolysis of Dog Erythrocytes and Lipid Peroxidation of Their Components, J Dent Res 65:1186-1190.

14.

I.S.O. (1978): Resin-based Dental Filling Materials, ISO 4049, International Organization for Standardization, Geneva, Switzerland.

15.

Kadoma, Y. ; Kojima, K. ; and Masuhara, E. (1986): Studies on Initiator Systems of Visible-light Curing Resins Using DSC, J Jpn Soc Dent Mater Dev 5:341-348.

16.

Kawaguchi, T. ; Kunimoto, S. ; and Kusumoto, K. (Tokuyama Soda Co.) (1985): Compositions for Self-cured Dentin Adhesive Resins, Jap Patent No. 135468.

17.

Komura, I. ; Yamauchi, J. ; Nagase, Y. ; and Shibatani, K. (Kuraray Co.) (1981): Photopolymerizable Compositions for Dental Materials, Jap Patent No. 120610.

18.

Lutz, F. and Phillips, W. (1983): A Classification and Evaluation of Composite Resin Systems, J Prosthet Dent 50:480-488. Mullken, R.S. (1952): Molecular Compounds and Their Spectra II, J Am Chem Soc 74:811-824.

19.

Munksgaard, E.C. ; Irie, M. ; and Asmussen, E. (1985): Dentin-polymer Bond Promoted by Gluma and Various Resins, J Dent Res 64:1409-1411.

20.

Onose, H. ; Sano, H. ; Kanto, H. ; Ando, S. ; and Hasuike, T. (1985): Selected Curing Characteristics of Light-activated Composite Resins, Dent Mater 1:48-54.

21.

Shintani, H. ; Inoue, T. ; and Yamaki, M. (1985): Analysis of Camphorquinone in Visible Light-cured Composite Resins, Dent Mater 1:124-126.

22.

Sluder, T.B. ; Sockwell, C.L. ; and Leinfelder, K.S. (1982): Two-year Clinical Evaluation of Two Light-cured Composite Resins, J Dent Res 61:214.

23.

Swartz, M.L. ; Phillips, R.W. ; and Rhodes, B. (1983): Visible Light-activated Resins-Depth of Cure, J Am Dent Assoc 106:634-637.

24.

Williams, D.F. and Cunningham, J. (1979): Materials in Clinical Dentistry. Oxford, England: Oxford Univ. Press, pp. 175-176.