It has been reported in the literature that after lasing dentin the dentin surface has a glassy or globular appearance. Many authors believe this to be recrystallized hydroxyapatite. The purpose of this elemental analysis was to see if any of the silica fiber optic was melted and deposited as these globular structures on the canal wall. Two teeth were used. One was hand-instrumented with files and used as the control, the other was lased with a holmium:YAG laser. A 245-mu low OH- fiber was used with a power setting of 0.75 W, 5 Hz, 94.2 J, and 1134 V to lase the root. The roots were microanalyzed for oxygen, phosphorus, silicon, nitrogen, hydrogen, calcium, and carbon. The percentages for all elements tested were the same for both teeth. Therefore, there was no silicon deposited onto the canal wall of the tooth that was lased. It is concluded that the low OH- silica fiber optic was not melted and deposited onto the dentinal canal wall.