Processing an Optical Fiber Tip Doped with TiO₂ for a High-peak Nd-YAG Laser

Abstract

The laser beam ordinarily comes out from the tip of the fiber, and moves straight to targeted tissues. This is the usual way to use the beam for surgical treatment. However, when the beam is applied for the incision of soft tissue, or the removal of melanin pigment in gingival tissue, a periodontal pocket, an infected root canal etc., a diffused and circumferential beam from the tip of the fiber, is more effective than an ordinary straight beam. An ordinary straight beam has difficulty making incisions in oral soft tissues and removing some outer layers of the gingiva.
To obtain a diffused and circumferential beam, the tip of the optical fiber must be processed. Some black colored substance such as carbon paste is applied on the tip portion of an optical fiber before passing through the laser beam.
In this experiment, we obtained a diffused beam in circumferential direction by doping with TiO₂ within a several millimeter portion of the tip of the fiber. Further, this experiment compared characteristics of the fiber before and after processing with TiO₂, using a laser power meter and a thermotracer.
As a result, a decreased beam of straight direction, and an increased beam for circumferential direction with a stable thermal distribution were observed at the tip of the optical fiber that was doped with TiO₂.
These results strongly suggest that processed fiber for a high-peak pulse Nd-YAG laser is useful in clinical applications.