Effect and application of CO 2 laser beam angle of incidence on different parts of the oral cavity using oral cavity endoscopes.
The CO 2 laser beam caused typical "V" form defects in living tissues directed at an incidence of 90 degrees .  In other cases the defects are elliptic.  By decreasing the angle of incidence of the laser beam, the depth of the laser crater decreases and the healthy tissues are also damaged.  The authors constructed a measuring instrument and performed geometric measurement in the oral cavity.  At an incidence of 90 degrees , considered by them to be optimal, the laser beam can reach the surface of the two third parts (medial and posterior) of the oral cavity only through reflection.  The authors constructed a laser endoscope with a fixed and revolving mirror.  Using this device they could not only direct the laser beam to the areas of the oral cavity that are accessible with difficulty but they could also achieve a laser beam incidence always close to 90 degrees .
Department of Oral and Maxillofacial Surgery, Semmelweis Medical University, Budapest, Hungary.
L
L
Gáspár
M
M
Kásler
M
M
Orosz
D019723:Endoscopes; D004867:Equipment Design; D006801:Humans; D053685:Laser Therapy / Q000295:instrumentation* / Q000379:methods; D009055:Mouth / Q000033:anatomy & histology / Q000601:surgery*