title: Comparison of clinical outcomes of endodontic microsurgery: 1 year versus long-term follow-up.
abstract: BACKGROUND
  The purpose of this study was to examine and compare the clinical outcome of endodontic microsurgery after 1 year of follow-up and over a period of 4 years.
  
  
  METHODS
  The database of the Department of Conservative Dentistry, Yonsei University, Seoul, South Korea, was searched for patients who had undergone endodontic microsurgery and had been evaluated 1 year after surgery and over a period of 4 years. Two examiners independently evaluated the postoperative radiographs taken 1 year after surgery and over a period of 4 years using Rud's criteria. To analyze and compare the success rate based on the observation period, the McNemar test was performed with a significance level of 0.05.
  
  
  RESULTS
  The study included 115 cases. Using Rud's criteria, the overall success rate of cases with 4 or more years of follow-up was 87.8% compared with 91.3% at 1 year of follow-up. There was no significant difference between the follow-up periods (P = .344).
  
  
  CONCLUSIONS
  There was no significant difference in the clinical outcome after endodontic microsurgery when comparing 1-year follow-up periods with longer follow-up periods.
authors.affiliation: Department of Conservative Dentistry, Gangnam Severance Dental Hospital, College of Dentistry, Yonsei University, Seoul, South Korea.
authors.forename: Minju
authors.initials: M
authors.lastname: Song
authors.affiliation: Department of Conservative Dentistry, Gangnam Severance Dental Hospital, College of Dentistry, Yonsei University, Seoul, South Korea.
authors.forename: Taekjin
authors.initials: T
authors.lastname: Nam
authors.affiliation: Microscope Center, Department of Conservative Dentistry and Oral Science Research Center, College of Dentistry, Yonsei University, Seoul, South Korea.
authors.forename: Su-Jung
authors.initials: SJ
authors.lastname: Shin
authors.affiliation: Microscope Center, Department of Conservative Dentistry and Oral Science Research Center, College of Dentistry, Yonsei University, Seoul, South Korea. Electronic address: andyendo@yuhs.ac.
authors.forename: Euiseong
authors.initials: E
authors.lastname: Kim
mesh_terms: D000328:Adult; D000368:Aged; D000369:Aged, 80 and over; D017607:Aluminum Compounds / Q000627:therapeutic use; D001047:Apicoectomy / Q000295:instrumentation / Q000379:methods*; D001861:Bone Regeneration / Q000502:physiology; D017610:Calcium Compounds / Q000627:therapeutic use; D017220:Dentin-Bonding Agents / Q000627:therapeutic use; D004338:Drug Combinations; D005260:Female; D005500:Follow-Up Studies; D006801:Humans; D008137:Longitudinal Studies; D008297:Male; D008768:Methylmethacrylates / Q000627:therapeutic use; D008866:Microsurgery / Q000295:instrumentation / Q000379:methods*; D008875:Middle Aged; D010087:Oxides / Q000627:therapeutic use; D059745:Piezosurgery / Q000295:instrumentation / Q000379:methods; D016300:Radiography, Bitewing / Q000379:methods; D012086:Reoperation; D012184:Retrograde Obturation / Q000379:methods; D012387:Root Canal Filling Materials / Q000627:therapeutic use; D017640:Silicates / Q000627:therapeutic use; D019227:Tooth Apex / Q000000981:diagnostic imaging; D014081:Tooth Extraction; D014092:Tooth Root / Q000601:surgery; D016896:Treatment Outcome; D055815:Young Adult; D015035:Zinc Oxide-Eugenol Cement / Q000627:therapeutic use
chemical_list: D017607:Aluminum Compounds; D017610:Calcium Compounds; D017220:Dentin-Bonding Agents; D004338:Drug Combinations; D008768:Methylmethacrylates; D010087:Oxides; D012387:Root Canal Filling Materials; D017640:Silicates; D015035:Zinc Oxide-Eugenol Cement; C086631:mineral trioxide aggregate; C031667:IRM cement; C084074:Super EBA
keywords: Clinical outcome; Rud's criteria; endodontic microsurgery; follow-up period