title: Ultrasonic instrumentation: comparing two teaching methods.
mesh_terms: D001296:Audiovisual Aids; D002983:Clinical Competence; D003777:Dental Prophylaxis / Q000295:instrumentation; D005069:Evaluation Studies as Topic; D013663:Teaching / Q000379:methods*; D014465:Ultrasonics / Q000295:instrumentation*; D014743:Videotape Recording