The argon laser is an alternative light source that can be used for the photopolymerization of resin-based dental materials and for tooth bleaching. The argon laser emits specific laser lines with wavelengths that correspond to the absorption peak of camphoroquinone, the initiator of polymerization for the adequate photocuring of resin composite. The collimated beam of the argon laser does not decrease with distance and an optical fiber has access to all cavity areas. In addition, the temperatures produced by an argon laser when curing resin-based materials and performing in-office tooth bleaching are significantly lower than those of conventional photocuring units. Argon is one of the three dental laser wavelengths that have been cleared by the FDA for tooth whitening. This article reviews the literature to examine the role that argon lasers can play in dental treatment.