title: Treatment of Mature Permanent Teeth with Necrotic Pulps and Apical Periodontitis Using Regenerative Endodontic Procedures: A Case Series.
abstract: BACKGROUND
  Regenerative endodontic procedures (REPs) are usually used to treat human immature permanent teeth with necrotic pulps and/or apical periodontitis. Successful REPs result in the elimination of clinical signs/symptoms, the resolution of apical periodontitis, and, in some cases, thickening of the canal walls and/or continued root development with or without apical closure. REPs can restore the vitality of tissue in the canals of immature permanent teeth previously destroyed by infection or trauma. Vital tissue is inherited with immune defense mechanisms to protect itself from foreign invaders. Recently, REPs have also been used to successfully treat human mature permanent teeth with necrotic pulps and apical periodontitis. The purpose of this case series was to present the potential of using REPs for mature permanent teeth with necrotic pulps and apical periodontitis.
  
  
  METHODS
  This case series consisted of 6 patients, 4 females and 2 males. The patients' ages ranged from 8-21 years old. Seven permanent teeth, 4 anterior and 3 molar teeth, with necrotic pulps and apical periodontitis were treated using REP. Radiographically, the root development of all teeth was almost completed except the apices of 2 molars, which showed slightly open. Complete chemomechanical debridement of the canals of the teeth was performed, and the canals were dressed with Metapaste (Meta Biomed Co, Ltd, Chungbuk, Korea) during treatment visits. Periapical bleeding into the canals was induced at the last treatment visit by placing a hand #20 or #25 K-file with the tip slightly bent through the apical foramina into the periapical tissues. A 3-mm thickness of mineral trioxide aggregate was placed into the coronal canals over semicoagulated blood. The access cavities were restored with either composite resin or amalgam.
  
  
  RESULTS
  Follow-ups of the 7 teeth ranged from 8 to 26 months. The periapical lesions of 2 teeth were considered healed, and 5 teeth revealed healing. Clinical signs/symptoms were absent in all teeth at follow-up visits at different time points. None of the treated teeth responded to cold and electric pulp tests.
  
  
  CONCLUSIONS
  This case series shows the potential of using REPs for mature teeth with necrotic pulp and apical periodontitis.
authors.affiliation: Department of Endodontics, Faculty of Dentistry, University of Benghazi, Benghazi, Libya.
authors.forename: Tarek Mohamed
authors.initials: TM
authors.lastname: Saoud
authors.affiliation: Department of Endodontics, Faculty of Dentistry, National University of Cordoba, Cordoba, Argentina.
authors.forename: Gabriela
authors.initials: G
authors.lastname: Martin
authors.affiliation: Department of Endodontics, Chi Mei Medical Center, Yong Kang and Liouying, Tainan, Taiwan.
authors.forename: Yea-Huey M
authors.initials: YH
authors.lastname: Chen
authors.affiliation: Department of Endodontics, Chi Mei Medical Center, Yong Kang and Liouying, Tainan, Taiwan.
authors.forename: Kuang-Liang
authors.initials: KL
authors.lastname: Chen
authors.affiliation: Department of Endodontics, Chi Mei Medical Center, Yong Kang and Liouying, Tainan, Taiwan.
authors.forename: Chao-An
authors.initials: CA
authors.lastname: Chen
authors.affiliation: Department of Endodontics, College of Dentistry, New York University, New York, New York.
authors.forename: Kamolthip
authors.initials: K
authors.lastname: Songtrakul
authors.affiliation: Department of Endodontics, College of Dentistry, New York University, New York, New York.
authors.forename: Matthew
authors.initials: M
authors.lastname: Malek
authors.affiliation: Department of Endodontics, College of Dentistry, New York University, New York, New York.
authors.forename: Asgeir
authors.initials: A
authors.lastname: Sigurdsson
authors.affiliation: Department of Endodontics, College of Dentistry, New York University, New York, New York. Electronic address: lml7@nyu.edu.
authors.forename: Louis M
authors.initials: LM
authors.lastname: Lin
mesh_terms: D000293:Adolescent; D002648:Child; D003790:Dental Pulp Necrosis / Q000000981:diagnostic imaging / Q000628:therapy*; D004708:Endodontics / Q000379:methods*; D005260:Female; D005500:Follow-Up Studies; D006801:Humans; D008297:Male; D010485:Periapical Periodontitis / Q000000981:diagnostic imaging / Q000628:therapy*; D011861:Radiography, Dental; D044968:Regenerative Medicine / Q000379:methods*; D023822:Tissue Engineering / Q000379:methods*; D055815:Young Adult
keywords: Apical periodontitis; immune defense mechanisms; mature teeth; necrotic pulps; regenerative endodontic therapy; vital tissue