title: Retrospective long-term analysis of bone level changes after horizontal alveolar crest reconstruction with autologous bone grafts harvested from the posterior region of the mandible.
abstract: OBJECTIVE
  The goal of this study was to evaluate the long-term success of horizontal alveolar crest augmentation of the retromolar region of the mandible with particulated bone, as well as factors affecting subsequent peri-implant bone loss.
  
  
  METHODS
  A total of 109 patients (68 female, 41 male) suffering from alveolar ridge deficiencies of the maxilla and mandible were included in this study. All patients were treated with particulated retromolar bone grafts from the mandible prior to the insertion of endosseous dental implants. Mesial and distal peri-implant crestal bone changes were assessed at six time points. Several parameters, including implant survival and the influence of age, gender, localisation of the implant, diameter, covering procedures, and time points of implant placement, were analysed to identify associations with bone level changes using the Mann-Whitney U-test, the Kruskal-Wallis test, and Spearman's rank-order correlation coefficient.
  
  
  RESULTS
  A total of 164 dental implants were placed in the maxilla (n=97) and in the mandible (n=67). The mean observation period was 105.26±21.58 months after implantation. The overall survival rate was 97.6% after 10 years. Overall, peri-implant bone loss was highest during the first year, but decreased over time. The mean amount of bone loss after 10 years was 2.47 mm mesially and 2.50 mm distally. Bone loss was significantly influenced by implant type and primary stability.
  
  
  CONCLUSIONS
  The use of particulated autologous retromolar bone grafts is a reliable technique for the horizontal reconstruction of local alveolar ridge deficiencies. Our results demonstrate that implants placed in augmented bone demonstrated similar bone level changes compared to implants inserted in non-augmented regions.
authors.affiliation: Department of Oral and Maxillofacial Surgery, Campus Virchow Clinic, Charité - Universitätsmedizin Berlin, Berlin, Germany .
authors.forename: Jan Oliver
authors.identifier: 0000-0002-1760-2599
authors.initials: JO
authors.lastname: Voss
authors.affiliation: Dental Practice, Belleza-Praxisklinik für Implantologie und Ästhetik, Berlin, Germany .
authors.forename: Tobias
authors.identifier: 0000-0001-5500-0647
authors.initials: T
authors.lastname: Dieke
authors.affiliation: Department of Oral and Maxillofacial Surgery, Campus Virchow Clinic, Charité - Universitätsmedizin Berlin, Berlin, Germany .
authors.forename: Christian
authors.identifier: 0000-0002-0439-759X
authors.initials: C
authors.lastname: Doll
authors.affiliation: Department of Oral and Maxillofacial Surgery, Campus Virchow Clinic, Charité - Universitätsmedizin Berlin, Berlin, Germany .
authors.forename: Claudia
authors.identifier: 0000-0002-6804-2149
authors.initials: C
authors.lastname: Sachse
authors.affiliation: Department of Oral and Maxillofacial Surgery, Medical Center - University of Freiburg, Freiburg, Germany .
authors.forename: Katja
authors.identifier: 0000-0002-0516-3234
authors.initials: K
authors.lastname: Nelson
authors.affiliation: Department of Oral and Maxillofacial Surgery, Campus Virchow Clinic, Charité - Universitätsmedizin Berlin, Berlin, Germany .
authors.forename: Jan-Dirk
authors.identifier: 0000-0003-4982-6105
authors.initials: JD
authors.lastname: Raguse
authors.affiliation: Department of Oral and Maxillofacial Surgery, Campus Virchow Clinic, Charité - Universitätsmedizin Berlin, Berlin, Germany .
authors.forename: Susanne
authors.identifier: 0000-0001-8522-0763
authors.initials: S
authors.lastname: Nahles
keywords: Alveolar ridge augmentation; Autografts; Bone resorption; Bone transplantation; Dental implants; Mandible