title: Periodontal Healing Distally to Second Mandibular Molar After Third Molar Coronectomy.
abstract: OBJECTIVE
  Coronectomy of mandibular third molars is a procedure that still raises a number of questions. The aim of the present study was to answer one unsolved question: the periodontal healing distal to the mandibular second molar after third molar coronectomy.
  
  
  METHODS
  A prospective cohort study was performed of 30 patients treated at the Unit of Oral and Maxillofacial Surgery of the Department of Biomedical and Neuromotor Science of the University of Bologna. The predictor variables were the probing pocket depth (PPD), the distance between the marginal crest (MC) and the bottom of the osseous defect (BOD), and the distance between the cementum enamel junction (CEJ) and the BOD. These clinical indexes were recorded on 3 points of the distal surface of second molar: the distobuccal (DB), distomedial (DM), and distolingual (DL) sites. The other variables evaluated included root migration and postoperative complications. The Wilcoxon test for paired data and Kendall's tau-b correlation coefficient was used to evaluate all variables. The significance level was set at P = .05.
  
  
  RESULTS
  The cohort was composed of 30 patients with 34 high-risk mandibular third molars (9 men and 21 women), with a mean age of 28 ± 7 years. At 9 months, a statistically significant reduction in the PPD of 2 ± 3, 1 ± 2, and 2 ± 2 mm and a statistically significant reduction in the MC-BOD distance of 4 ± 4, 4 ± 4, and 4 ± 5 mm for the DB, DM, and DL sites, respectively, was observed (P = .001). Also, the intraoperative CEJ-BOD distance showed a statistically significant reduction for the DB, DM, and DL sites.
  
  
  CONCLUSIONS
  After coronectomy, restoration of a clinical healthy periodontium distal to the second molar was observed. However, further studies are necessary to confirm these preliminary clinical results and to compare periodontal healing between coronectomy and complete extraction.
authors.affiliation: PhD Student, Unit of Oral and Maxillofacial Surgery, Department of Biomedical and Neuromotor Science, University of Bologna, Bologna, Italy. Electronic address: elisabetta.vignudelli@unibo.it.
authors.forename: Elisabetta
authors.initials: E
authors.lastname: Vignudelli
authors.affiliation: Visiting Professor, Unit of Oral and Maxillofacial Surgery, Department of Biomedical and Neuromotor Science, University of Bologna, Bologna, Italy.
authors.forename: Giuseppe
authors.initials: G
authors.lastname: Monaco
authors.affiliation: Researcher, Unit of Oral and Maxillofacial Surgery, Department of Biomedical and Neuromotor Science, University of Bologna, Bologna, Italy.
authors.forename: Maria Rosaria Antonella
authors.initials: MR
authors.lastname: Gatto
authors.affiliation: Clinical Fellow, Unit of Oral and Maxillofacial Surgery, Department of Biomedical and Neuromotor Science, University of Bologna, Bologna, Italy.
authors.forename: Simonetta
authors.initials: S
authors.lastname: Franco
authors.affiliation: Professor of Maxillofacial Surgery, Unit of Oral and Maxillofacial Surgery, Department of Biomedical and Neuromotor Science, University of Bologna, Bologna, Italy.
authors.forename: Claudio
authors.initials: C
authors.lastname: Marchetti
authors.affiliation: Assistant Professor, Unit of Oral and Maxillofacial Surgery, Department of Biomedical and Neuromotor Science, University of Bologna, Bologna, Italy.
authors.forename: Giuseppe
authors.initials: G
authors.lastname: Corinaldesi
mesh_terms: D000293:Adolescent; D000328:Adult; D005260:Female; D006801:Humans; D008297:Male; D008334:Mandible; D008875:Middle Aged; D008964:Molar, Third / Q000601:surgery*; D010512:Periodontal Index; D010519:Periodontium / Q000601:surgery; D011446:Prospective Studies; D000072836:Surgical Wound; D014095:Tooth, Impacted / Q000601:surgery*; D014945:Wound Healing; D055815:Young Adult