Invitro Effect of Er:YAG laser on exposed dentinal tubules

This study was designed to evaluate the effects of Er:YAG laser exposure with different parameters on exposed dentin in human teeth in vitro, using scanning electron microscope and stereo- microscope examination. 40 impacted third molars were prepared and divided into 3 groups (A, B, and C). Group A (control group) included 40 un-exposed lingual halves. Group B and C (experimental groups) 20 buccal halves for each were irradiated with exactly the same exposure parameters (Energy = 200 mj , Frequency = 5 Hz, ,Pulse duration = 5 milliseconds, Mode = XLP ), with extreme long pulse and contact mode. The time of exposure was 15 seconds for group B and 30 seconds for group C. The specimens were studied by both scanning scanning electron microscope (SEM) and stereo-microscope. Extension of the laser exposure irradiation time produced more melting effects on dentin surface with maintenance of pulp safety