The Sealing Properties of Methyl 2-Cyanoacrylate as an Adhesive in Dentistry

The Sealing Properties of Methyl 2-Cyanoacrylate as an Adhesive in Dentistry MOHAMED A. F. KHOWASSAH and ERNEST A. SAHS Department of Operative Dentistry, University of Iowa, Iowa City, Iowa SYNOPSIS IN INTERLINGUA LE PROPRIETATES IMPERMEABILISATORI DE 2-CYANOACRYLATO METHYLIC USATE COMO AGENTE ADHESIVE IN LE DENTISTERIA.-Le proprietates impermeabilisatori de adhesive 2-cyanoacrylato methylic esseva comparate con illos de varie materiales de cementation que es currentemente usate in le dentisteria. 2cyanoacrylato methylic, cemento a phosphate de zinc, cemento a oxydo de zinc e eugenol, e cemento Grip esseva usate in cementar applicatos plastic a platte superficies de 36 extradite dentes human. Per le uso de un dica de cauchu il esseva rendite possibile exponer solo le areas de ligage a un blauastre solution colorante de 0,5 pro cento de eosina durante imitate periodos de tempore e a varie temperatures. Adhesive 2-cyanoacrylato methylic (monomero Eastman 910) manifestava un capacitate superior de impermeabilisation le qual justificava investigationes additional de iste substantia adhesive. Le resultatos del altere investigationes va esser reportate in tempores veniente. For many years, dentistry has been concerned with the problems of true adherence of the restorative materials to the tooth structure.' Many studies have indicated that there is marginal leakage with the restoration materials currently available.2-5 The present restorative materials have thermal coefficients of expansion and contraction different from those of the tooth structure.' This factor contributes to the problem of marginal leakage.4 Marginal leakage of all the restorative materials, resulting from loss of adhesion between the restoration and the cavity walls and the difference in the thermal coefficient of expansion and contraction, could be a contributing factor to: (1) recurrent caries around restorations, (2) continuous insult to the vital pulp, (3) hypersensitivity of some restored teeth, and (4) eventual loss of the restoration. These have been common problems for the practicing dentist." 4 ' There i,, however, agreement between dental investigators that the ideal restorative material, which truly seals the cavity margins without sacrificing more tooth structure, is yet to be developed.7 Recent research indicates that the ideal restorative material should be able to bond This research was supported by U.S. Public Health Service Grant No. F.R-S.0.1-2-64 from the National Institutes of Health, Bethesda, Md. Received for publication May 21, 1965. 376 or adhere chemically and physically with the tooth structure and still possess the esthetic and physical requirements for a restorative material.8' 9 Numerous new household and commercial adhesives have been shown to create strong bonds between various materials. In most of these, bond results are close to the advertising claims. These adhesives have aroused the interest within the dental profession, where the need for a bonding adhesive restorative material has always been a challenge to dental investigators. This in vitro pilot study wan intended to investigate the sealing property of a commercial adhesive* for application in restorative dentistry. The monomer (methyl 2-cyanoacrylate) has been investigated by some medical researchers. A number of investigations have been published concerning the use of this monomer as an adhesive in different surgical fields. No serious harmful effect has yet been discovered from this adhesive.'O~9 It was theorized that, if an adhesive could maintain a good seal and a strong bond despite the dimensional fluctuation of tile restoration, this adhesive would merit further consideration for use in restorative dentistry. * Eastman 910 monomer, developed by Tennessee Eastman Co., Division of Eastman Kodak Co., Kingsport, Tenn. Vol. 45, No. 2 DENTAL SEALING PROPERTIES OF METHYL 2-CYANOACRYLATE 377 Materials and Methods The dye penetration method was used to test the sealing property of the adhesive, methyl 2-cyanoacrylate. This adhesive was compared with cements presently used in restorative dentistry. These were zinc phosphate cement, zinc oxide-eugenol cement, and a resin cement. Flat plane, nonretentive surfaces were prepared on 36 human teeth. Plastic onlays were constructed to fit accurately the prepared tooth surfaces. The plastic restorative material was used in this study because of its dimensional instability when exposed to environmental changes. The teeth were allotted to four groups of 9 teeth each. Methyl 2-cyanoacrylate adhesive, zinc phosphate cement, zinc oxideeugenol cement, and grip cement were each used as the adhesive in one of the four groups, respectively. Methyl 2-cyanoacrylate was applied as a thin film. Manufacturer's instructions were followed in mixing the zinc phosphate cement and the grip cement. Zinc oxideeugenol cement was used as a medium mix. Digital pressure was applied to the adherents when methyl 2-cyanoacrylate was used as the adhesive. An aqueous 0.5 per cent eosin dye solution was prepared and used at 700 C. and 30 C. By the use of the rubber dam, only the bonding areas were exposed to the dye solutions. Three teeth from each group were put into the 700 C. dye solution for 15 minutes and removed. Three other teeth from each group were put into the 30 C. dye solution TABLE 1 RESULTS OF THE DYE PENETRATION EXPERIMENT Adhesive and Cementing Materials Methyl 2-cyanoacrylate adhesive Zinc phosphate 700 C. Minutes 3° C. is Minutes Cycling is Minutes None None XX XX Questionable XXX X X X X 15 cement Zinc oxide-eugenol cement Grip cement X XX for 15 minutes and removed. The remaining 3 teeth from each group were exposed to the 700 C. dye solution for 1 minute. They were then removed and placed immediately into the 30 C. dye solution for 1 minute. This was repeated 15 times (cycles). This will be mentioned later as the cycling test. All of the exposed bonds were washed under running water for 5 minutes. All bonds, after being broken, were examined under a dissection microscope, using X3 and X6 magnifications for the purpose of observing the degree of dye penetration into the prepared tooth surface. The amount of dye penetration was graded by the following system: Enamel penetration X Enamel and beginning dentin penetration XX Enamel and half dentin penetration XX Enamel and all dentin penetration X X X Results At 700 C. and 30 C., with methyl 2cyanoacrylate adhesive there was no dye penetration and with zinc phosphate cement there was considerable dve penetration into the dentin surface (Table 1). With zinc oxide-eugenol cement, there was slight dye penetration of the enamel region only. With grip cement, there was slight dye penetration of the enamel only. In the cycling test, with methyl 2-cyanoacrylate adhesive there was a slight amount of dye penetration, which could be penetration through the enamel and not through the adhesive. With zinc phosphate cement, there was obvious dye penetration through most of the dentin surface and more than that demonstrated in either the 700 C. test or the 30 C. test alone. Zinc oxide-eugenol cement allowed dye penetration into the enamel region only. Grip cement* allowed dye penetration into the enamel region and the beginning of the dentin region. Discussion The dye penetration test was used in this experiment to demonstrate the sealing abilities of the adhesives and the cementing materials. If the material used as an adhesive can demonstrate resistance to dye penetra* Grip cement, L. D. Caulk Co., Milford, Del. 378 KIOWASSAH AND SALS tion, this would indicate good sealing properties. From the results, methyl 2-cyanoacrylate adhesive was the most resistant to dye penetration in all three phases of the experiment. A questionable amount of dye penetration was observed with the adhesive after the cycling test. This might indicate some dimensional changes of the adhesive with temperature variations. Zinc oxide-eugenol cement was a close second to the methyl 2-cyanoacrylate adhesive through all the three phases of the test. This result agreed with what Norman, Swartz, and Phillips20 concluded from studying the sealing abilities of dental cements. Grip cement followed the zinc oxide and eugenol cement in its ability to resist the dye penetration. Temperature changes had an evident effect on the Grip cement when it was subjected to the cycling test. This dimensional change could be attributed to the fact that Grip cement is an acrylic resin cement. The zinc phosphate cement had the lowest resistance to dye penetration in all the three phases of the experiment. From the results, it was concluded that the methyl 2-cyanoacrylate adhesive had promising sealing qualities. This does not in any way mean that the answer to the marginal leakage problem had been found. The adhesive has shown promising qualities, however, which encouraged further investigation. Some of the other properties investigated were adhesive strength, effect of moisture on the adhesive, and the effect of temperature variation on the adhesive bond. The result of the test will be reported later. Summary The sealing properties of methyl 2-cyanoacrylate adhesive were compared to those of different cementing materials currently used in dentistry. The adhesive and the cements were used to cement plastic onlays to flat surfaces of 36 extracted human teeth. Methyl 2-cyanoacrylate adhesive exhibited superior sealing ability, which justified further investigation of this adhesiv e. Thanks are expressed to Ethicon Inc., Somerville, N.J., for supplying the methyl 2-cyanoacrylate adhesive. J. dent. Res. March-April 1966 References 1. PHILLIPS, R. W. Certain Biological Considerations in the Use of Restorative Materials, N.Y. State dent. J., 28:397, 1962. 2. ARMSTRONG, W. O., and SIMON, W. J. Penetration of Radiocalcium at the Margins of Filling Materials, A Preliminary Report, J. Amer. dent. Ass., 43:684, 1951. 3. GILMORE, W. H., SWARTZ, M. L., and PHILLIPS, R. W. Adaptation of in Vivo Restorations as Assessed by Ca45, J. dent. Res., 36:754, 1959. 4. WALLCOTT, R. B., and NELSON, R. J. A Method for Evaluating Adaptation of Resotration, J. dent. Res., 30:500, 1951. 5. MASSLER, M., and GOING, R. E., Marginal Penetration of Various Isotopes Around Different Filling Materials, J. dent. Children, 4th Quarter, p. 319, 1959. 6. SKINNER, E. W., and PHILLIPS, R. W. The Science of Dental Materials, ed. 5, Philadelphia, W. B. Saunders Co., 1962, p. 28. 7. PHILLIPS, R. W. Report of the Committee on Scientific Investigation of the American Academy of Restorative Dentistry, J. Pros. dent., 13:516, 1963. 8. BUONOCOR, M. G. Tests of an Adhesive Containing Glycerophosphoric Acid DIimethacrylate, In PHILLIPS, R. W., and RYGE, G. (editors), Adhesive Restorative Materials. Spenser, Ind., Owens Lithograph, 1961, p. 172. 9. EIRICH, F. Summary Session. In PHILLIPS, R. W., and RYGE, G. (editors), A dhesive Restorative Materials. Spenser, Ind., Owens Lithograph, 1061, p. 209. 10. ALBIN, M. S., D'AGOSTINE, A. N., WHITE, R. J. and GRINDLAY, J. H. Nonsuture Sealing of a Dural Substitute Utilizing a Plastic Adhesive Methyl 2cyanoacrylate, J. Neurosurg., 19:545-50, 1962. 11. AWE, W., ROBERTS, W., and BRAUNWALD, N. S. Rapidly Polymerizing Adhesive as a Hemostatic Agent, Study of Tissue Response and Bacteriological Properties, Surgery, 54:322, 1963. 12. BLOOMFIELD, S., BARNETT, A. H., and KANTER, P. D. The Use of Eastman 910 Monomer as an Adhesive in Ocular Surgery, I. Biological Effects on Ocular Tissues, J. Ophthal., 55:742, 1963. 13. HAFNER, C. D., FOGARTY, T. J., and CRANLEY, J. J. Nonsuture Anastomosis of Small Arteries Using a Tissue Adhesive, Surg., Gynecol. &D Obstet., 116:417, 1963. 14. O'NEILL, P., HEALEY, J. E., CLARK, R. L., and GALLAGHER, H. S. Nonsuture Intestinal Anastomosis, Amer. J. Surg., 104:761, 1962. 15. JOHN, L. S., and VASKO, J. Sealing Cut Lung Surfaces with Plastic Adhesive, J. thorac. a cardiovasc. Surg., 46:526, 1963. 16. SHAFF, S. I. A Plastic Adhesive for Nonsuture Repair of Tracheal Wounds, J. Amer. vet. med. Ass., 143:158, 1963. 17. STONE, H. H. Nonsuture Closure of Cutaneous Laceration, Skin Grafting and Bowel Anastomosis, Amer. Surgeon, 30:177, 1964. 18. STRAHAN, R. W., SAJEDEE, M., and DUVAL, M. K. The Leaking Esophageal Suture Line, A New Method of Repair Using Eastman 910 Adhesive, Amer. J. Surg., 106:570, 1963. 19. WILDER, R. J., PLAYFORTH, H. BRYANT, M:, and RAVITcH, M. M. The Use of Plastic Adhesive in Pulmonary Surgery, J. thorac. &I cardiovasc. Surg., 46:576,1963. 20. NORMAN, R. D., SWARTZ, M. L., and PHILLIPS, R. W. Studies on the Film Thickness, Solubility, and Cavity Sealing Ability of Dental Cements. l.A.D.R., March, 1962, p. 86.