title: The Effect of Maxillary First Molar Root Length on the Success Rate of Buccal Infiltration Anesthesia.
abstract: BACKGROUND
  Several variables may influence anesthesia success in maxillary molars. This investigation was conducted to evaluate the effect of root length on the success rate of infiltration injections of 2% lidocaine with 1:80,000 epinephrine.
  
  
  METHODS
  One hundred maxillary first molars with irreversible pulpitis were treated. After the administration of a buccal infiltration injection of 2% lidocaine with 1:80,000 epinephrine, the patients' pain during dentin cutting, pulp exposure, and root canal instrumentation were evaluated using the Heft-Parker visual analog scale. No or mild pain was considered as success. Data were analyzed by the point-biserial correlation test and receiver operating characteristic curve analysis.
  
  
  RESULTS
  Overall, 61% of the teeth had successful anesthesia after the administration of a single buccal infiltration injection of anesthetic solution. The point-biserial correlation test showed that the teeth that had palatal and distobuccal roots with longer root lengths showed significantly higher anesthesia failure (P < .05). However, receiver operating characteristic curve analysis did not show a clinically useful cutoff point of root length corresponding with anesthesia failure.
  
  
  CONCLUSIONS
  Maxillary first molars having irreversible pulpitis with longer roots may have more anesthesia failures after a single buccal infiltration injection with 2% lidocaine and 1:80000 epinephrine.
authors: Oral and Dental Diseases Research Center, Kerman University of Medical Sciences, Kerman, Iran.
authors: Ehsan
authors: E
authors: Moradi Askari
authors: Endodontology Research Center, Kerman University of Medical Sciences, Kerman, Iran. Electronic address: masoudparirokh@gmail.com.
authors: Masoud
authors: M
authors: Parirokh
authors: Neuroscience Research Center, Kerman University of Medical Sciences, Kerman, Iran.
authors: Nouzar
authors: N
authors: Nakhaee
authors: Endodontic Department, Dental School, Khorasan Shomali University of Medical Sciences, Bojnord, Iran.
authors: Hamid Reza
authors: HR
authors: Hosseini
authors: School of Dentistry, University of Western Australia, Perth, Australia.
authors: Paul V
authors: PV
authors: Abbott
mesh_terms: D000278:Administration, Buccal; D000328:Adult; D000766:Anesthesia, Dental / Q000379:methods*; D000772:Anesthesia, Local / Q000379:methods*; D000779:Anesthetics, Local / Q000008:administration & dosage*; D003782:Dental Pulp / Q000187:drug effects; D005260:Female; D006801:Humans; D008297:Male; D008963:Molar / Q000033:anatomy & histology* / Q000187:drug effects*; D011446:Prospective Studies; D011671:Pulpitis / Q000188:drug therapy*; D012390:Root Canal Therapy / Q000379:methods; D014092:Tooth Root / Q000033:anatomy & histology* / Q000187:drug effects*
chemical_list: D000779:Anesthetics, Local
keywords: Anesthesia; infiltration; irreversible; length; lidocaine; maxillary; molar; pulpitis; root; success