title: Microscope magnification and ultrasonic precision guidance for location and negotiation of second mesiobuccal canal: An in vivo study.
abstract: OBJECTIVE
  The aim of this study was to evaluate the influence of using the dental operating microscope (DOM) and ultrasonics for the detection of second mesiobuccal (MB2) canal orifice in maxillary first molars.
  
  
  METHODS
  Sixty subjects seeking root canal therapy for maxillary first molar were assessed for the presence of MB2 canal using endodontic explorer without magnification. Teeth in which the MB2 canal orifice could not be located were examined under magnification using DOM. If the MB2 canal orifice could not be found even after using DOM, ultrasonic tips were used to prepare 3-mm-long trough from the mesiobuccal canal orifice toward the palatal canal and examined under DOM for location of the canal.
  
  
  RESULTS
  With naked eye, the MB2 canal was located in 12 teeth; with the use of the DOM, the MB2 canal was located in 21 additional teeth; and with the combined use of ultrasonic tip and DOM, the MB2 canal was located in 9 more teeth. Statistical comparisons between the tested techniques were done by analyzing the Receiver Operating Characteristic (ROC) curves; a statistically significant difference was found (P < 0.001).
  
  
  CONCLUSIONS
  The results of this study indicate that the DOM and ultrasonics provide increased opportunity for the dentist to detect canal orifices.
authors.affiliation: Department of Conservative Dentistry, Sri Jagadguru Murugarajendra Dental College and Hospital, Chitradurga, India.
authors.forename: Ramachandra
authors.initials: R
authors.lastname: Sujith
authors.affiliation: Department of Conservative Dentistry, Sri Jagadguru Murugarajendra Dental College and Hospital, Chitradurga, India.
authors.forename: Kiranmurthy
authors.initials: K
authors.lastname: Dhananjaya
authors.affiliation: Department of Conservative Dentistry, KLE Viswanath Katti Institute of Dental Sciences, Belgaum, India.
authors.forename: Vishwajit Rampratap
authors.initials: VR
authors.lastname: Chaurasia
authors.affiliation: Department of Oral and Maxillofacial Pathology, (AME) Academy of Medical Education's dental college Dental College and Hospital, Raichur, Karnataka, India.
authors.forename: Deepa
authors.initials: D
authors.lastname: Kasigari
authors.affiliation: Department of Prosthodontics, Sri Jagadguru Murugarajendra Dental College and Hospital, Chitradurga, India.
authors.forename: Anusha Channabasappa
authors.initials: AC
authors.lastname: Veerabhadrappa
authors.affiliation: Department of Public Health Dentistry, Sri Jagadguru Murugarajendra Dental College and Hospital, Chitradurga, India.
authors.forename: Sachin
authors.initials: S
authors.lastname: Naik
keywords: Dental operating microscope; maxillary first molar; second mesiobuccal canal; ultrasonics