Morphological Changes in the Caries Excavated Dentin Prepared by Rotary, Carisolv ™ and Er, Cr: YSGG Laser (Biolase ™ ) Instruments: A Scanning Electron Microscopic Evaluation

The in vitro study presented in this article was performed to evaluate the morphological changes in caries excavated dentin after using three different caries removal methods. These methods include mechanical, chemomechanical (Carisolv™) and Er, Cr: YSGG Laser (Biolase™) by means of scanning electron microscope. Extracted carious human molars were ground to flat surfaces to expose caries surrounded by sound dentin. The caries were then removed with tungsten carbide bur and airotor handpiece (G1), by chemomechanical (Carisolv™) method (G2), and by irradiation with an Er, Cr: YSGG Laser (Biolase™) unit (G3). The samples were then observed under a scanning electron microscope (SEM) with different magnification powers (×800, ×2000 and ×5000). SEM study revealed a considerable difference in the surface characteristics of the dental tissue. The surface which was treated with Er, Cr: YSGG laser (Erbium, Chromium: Yttrium – Scandium – Gallium – Garnet) showed the best result with no residual smear layer followed by surfaces which were chemomechanically excavated with Carisolv™ gel. The treatment with mechanical method resulted in a surface with a smear layer without any micro retention. Thus, from the results obtained, it was concluded that Er, Cr: YSGG laser produced a scaly, irregular and rugged tooth surface without smear layer, which can be of highly retentive nature. Carisolv™ treated dentin showed uneven surfaces with many undermined areas. There were partially patented dentinal tubules and residues of contaminant smear layer. The dentin surfaces prepared using tungsten carbide bur and spoon excavator produced smearing and smear plugs in the tubular orifices.