[Effect of microwave on the dentin of root canal wall].
OBJECTIVE
To investigate the effect of microwave on dentin of root canal wall.


METHODS
Ten pairs of clinically sound single rooted premolars(totally 30 root canals: 10 teeth had only one calal and 10 had two canals) were collected. The root canals were treated with microwave of different irradiation energy except one canal of the two canal teeth, they were served as controls. The teeth were dissected longitudinally into two parts and prepared for SEM examination.


RESULTS
The microwave of 35 mA irradiated for 3 seconds would not damage the dentin and was safe for clinical usage. But, microwave over 75 mA or with a prolonged irradiation time could damage the dentin of the root canal wall to different extents. The damaged dentin presented incomplete fractures. At the same time, such damage also involved another canal in the same tooth which was not treated with microwave.


CONCLUSIONS
It is necessary to choose a suitable level of energy and control the irradiation time when a root canal is sterilized by microwave.
Yue
L
L
School of Stomatology, Beijing Medical University, Beijing 100081.
Wang
Z
Z
Wang
J
J
D000293:Adolescent; D000328:Adult; D002648:Child; D003786:Dental Pulp Cavity / Q000528:radiation effects* / Q000648:ultrastructure; D003804:Dentin / Q000528:radiation effects* / Q000648:ultrastructure; D004307:Dose-Response Relationship, Radiation; D006801:Humans; D008855:Microscopy, Electron, Scanning; D008872:Microwaves