Bonding of resin composite to carbon dioxide laser-modified human enamel.

OBJECTIVES Irradiation of enamel with carbon dioxide (CO2) laser energy alters physical and chemical properties of the enamel surface, and these lasers hold promise for conditioning enamel for bonding of adhesive restorations. This laboratory study examined the influence of laser irradiation parameters on the shear bond strength obtained for laser etching using a hybrid composite. METHODS Standardized surfaces prepared on 110 non-carious intact extracted anterior teeth were exposed to CO2 laser energy (9 different laser exposure parameters) or etched with orthophosphoric acid. RESULTS Laser treatment under defined conditions (power density 2380 W/cm2, energy density 23.8 J/cm2) resulted in a bond strength of 30.0 +/- 4.7 MPa, which exceeded that obtained for acid etching (17.9 +/- 4.3 MPa, p < 0.0001). Cohesive failure occurred within the bonding resin in this group. SIGNIFICANCE These data indicate that CO2 laser etching may enhance the bonding of resin composite to human enamel.

[1]  J. Featherstone,et al.  Laser irradiation of human dental enamel and dentine. , 1986, The New Zealand dental journal.

[2]  H. Stanley.  Guest Editorial: An Urgent Plea for a Standardized Bonding (Adhesion) Test , 1993, Journal of dental research.

[3]  K L Zakariasen,et al.  Spotlight on lasers. A look at potential benefits. , 1991, Journal of the American Dental Association.

[4]  L. Walsh.  Clinical evaluation of dental hard tissue applications of carbon dioxide lasers. , 1994, Journal of clinical laser medicine & surgery.

[5]  C. S. Fowler,et al.  Influence of selected variables on adhesion testing. , 1992, Dental materials : official publication of the Academy of Dental Materials.

[6]  J. Featherstone,et al.  Laser Effects On Dental Hard Tissues , 1987, Advances in dental research.

[7]  Laurence J. Walsh,et al.  Differential thermal effects of pulsed vs. continuous CO2 laser radiation on human molar teeth , 1994 .

[8]  C. P. Shields,et al.  Effect of pulsed low energy infrared laser irradiation on artificial caries-like lesion formation. , 1986, Caries research.

[9]  O. Fejerskov,et al.  Variation in the pattern of acid etching of human dental enamel examined by scanning electron microscopy. , 1975, Caries research.

[10]  D P Roberts-Harry,et al.  Laser etching of teeth for orthodontic bracket placement: A preliminary clinical study , 1992, Lasers in surgery and medicine.

[11]  I. Anić,et al.  [Composite retention area produced by CO2 laser beam]. , 1991, Acta stomatologica Croatica.

[12]  R Liberman,et al.  Adhesion of composite materials to enamel: Comparison between the use of acid and lasing as pretreatment , 1984, Lasers in surgery and medicine.

[13]  R F Sognnaes,et al.  Lased Enamel: Ultrastructural Observations of Pulsed Carbon Dioxide Laser Effects , 1972, Journal of dental research.

[14]  J. Palamara,et al.  Effects of continuous-wave CO2 laser on the ultrastructure of human dental enamel. , 1989, Archives of oral biology.

[15]  J A von Fraunhofer,et al.  Laser etching of enamel for direct bonding. , 1993, The Angle orthodontist.

[16]  F. Rueggeberg.  Substrate for adhesion testing to tooth structure - review of the literature. , 1991, Dental materials : official publication of the Academy of Dental Materials.

[17]  J A Hess,et al.  Scanning electron microscopic study of laser‐induced morphologic changes of a coated enamel surface , 1990, Lasers in surgery and medicine.