title: Ridge alterations post-extraction in the esthetic zone: a 3D analysis with CBCT.
abstract: Dimensional alterations of the facial bone wall following tooth extractions in the esthetic zone have a profound effect on treatment outcomes. This prospective study in 39 patients is the first to investigate three-dimensional (3D) alterations of facial bone in the esthetic zone during the initial 8 wks following flapless tooth extraction. A novel 3D analysis was carried out, based on 2 consecutive cone beam computed tomographies (CBCTs). A risk zone for significant bone resorption was identified in central areas, whereas proximal areas yielded only minor changes. Correlation analysis identified a facial bone wall thickness of ≤ 1 mm as a critical factor associated with the extent of bone resorption. Thin-wall phenotypes displayed pronounced vertical bone resorption, with a median bone loss of 7.5 mm, as compared with thick-wall phenotypes, which decreased by only 1.1 mm. For the first time, 3D analysis has allowed for documentation of dimensional alterations of the facial bone wall in the esthetic zone of humans following extraction. It also characterized a risk zone prone to pronounced bone resorption in thin-wall phenotypes. Vertical bone loss was 3.5 times more severe than findings reported in the existing literature.
authors.affiliation: University of Berne, Freiburgstrasse 7, Berne, 3010, Switzerland.
authors.forename: V
authors.initials: V
authors.lastname: Chappuis
authors.forename: O
authors.initials: O
authors.lastname: Engel
authors.forename: M
authors.initials: M
authors.lastname: Reyes
authors.forename: K
authors.initials: K
authors.lastname: Shahim
authors.forename: L-P
authors.initials: LP
authors.lastname: Nolte
authors.forename: D
authors.initials: D
authors.lastname: Buser
mesh_terms: D000328:Adult; D000368:Aged; D016301:Alveolar Bone Loss / Q000000981:diagnostic imaging; D000539:Alveolar Process / Q000000981:diagnostic imaging*; D059925:Anatomic Landmarks / Q000000981:diagnostic imaging; D001862:Bone Resorption / Q000000981:diagnostic imaging; D003094:Collagen / Q000627:therapeutic use; D054893:Cone-Beam Computed Tomography / Q000379:methods*; D003481:Cuspid / Q000601:surgery; D004955:Esthetics, Dental; D005260:Female; D005500:Follow-Up Studies; D006801:Humans; D021621:Imaging, Three-Dimensional / Q000379:methods*; D007180:Incisor / Q000601:surgery; D008297:Male; D008875:Middle Aged; D010641:Phenotype; D011446:Prospective Studies; D019252:Radiography, Dental, Digital / Q000379:methods; D014081:Tooth Extraction; D020390:Tooth Socket / Q000000981:diagnostic imaging*; D055815:Young Adult
chemical_list: D003094:Collagen
keywords: bone remodeling; bone resorption; clinical trial; dental implants; maxilla; three-dimensional imaging