13th World Congress for Laser Dentistry

26-28, April 2012

Barcelona, Spain

Meeting Abstract

Sponsors: World Federation for Laser Dentistry

-  Poster 40

TITLE: Influence of a blue DPSS laser on specimen thickness of composite resins.

AUTHORS: Kwon YH, Kim HI, Hur B, Park JK.                    

Pusan National University, Yangsan, Korea

SOURCE:  Med Oral Patol Oral Cir Bucal. 2012 May 1;17(Supplement1):S188.

* doi:10.4317/medoral.17643688

http://dx.doi.org/10.4317/medoral.17643688

Abstract

Introduction: Application of lasers in dentistry has a long history owing to their potential as light sources for treatment.

Aim of the study: The purpose of the present study was to examine the effect of a 473 nm DPSS laser on the specimen thickness (curing depth) of composite re-sins.

Materials and methods: Three different composite resins and light-curing units (LCUs) [quartz-tungsten-halogen (HX), light-emitting-diode (DE), and diode-pumped solid state laser (DPSS)] were used. The number of photons transmitted through the specimens, degree of conversion (DC), microhardness, and refractive index were evaluated as a function of the specimen thickness.

Results: The incident light decreased exponentially within the specimens. Among the LCUs, HX showed the least photon loss. The DC obtained using DPSS and HX was significantly greater (p<0.001) than that obtained using DE. The specimens light cured using DPSS showed slightly lowermicrohardness on both the top and bottom surfaces than that by DE and HX. At each depth, the mean refractive index was similar regardless of the LCUs used.

Conclusion: The DC, microhardness and refractive index showed an inverse linear correlation with the specimen thickness despite the exponential decrease in the number of photons. On the other hand, DC, microhardness and refractive index showed a linear correlation with each other, regardless of the LCUs.