title: Ridge preservation after ridge expansion with simultaneous guided bone regeneration: a preclinical study.
abstract: OBJECTIVE
  To evaluate ridge preservation after ridge splitting with simultaneous implant placement and guided bone regeneration (GBR) in a miniature pig model.
  
  
  METHODS
  In miniature pigs, the mandibular premolars and first molars were extracted together with removal of the interdental and buccal bone. Three months later, ridge splitting and expansion of the buccal plate were performed with simultaneous placement of two titanium implants per quadrant. On the test side, access by a mucoperiosteal flap followed by GBR with a biphasic calcium phosphate and a collagen membrane was performed. On the contralateral control side, a mucosal flap (MF), leaving the periosteum attached to the buccal bone, was elevated. After healing periods of 6 and 12 weeks, eight and four animals, respectively, were sacrificed for histological and histometric evaluation.
  
  
  RESULTS
  In the MF group, all 16 implants were osseointegrated, while in the GBR group, one bone fracture occurred, and six of 16 implants were lost. After 6 weeks, significantly higher bone crest levels were found for the GBR group than for the MF group both buccally and lingually (P < 0.001), and buccal bone thickness was greater in the GBR group than in the MF group (P < 0.001 at the implant shoulder [IS]). After 12 weeks, bone was significantly higher in the GBR group compared to the MF group. Furthermore, buccal bone thickness in the GBR group was 0.93, 4.5, and 5.94 mm at, and 2 and 4 mm apical to the IS, respectively. The corresponding values in the MF group were greatly reduced (0, 0.21, and 2.56 mm). Bone loss on the buccal side compared to the lingual side was significantly greater only in the MF group.
  
  
  CONCLUSIONS
  In this ridge expansion model in miniature pigs, the buccal bone volume was significantly better preserved with GBR when compared to a mucosal access flap, provided that soft tissue healing occurred complication free.
authors.affiliation: Department of Oral and Maxillofacial Surgery, University Hospital of Freiburg, Freiburg, Germany. andres.stricker@uniklinik-freiburg.de.|Center of Implantology, Periodontology and 3D Head- and Neck Diagnostics, Konstanz, Germany. andres.stricker@uniklinik-freiburg.de.
authors.forename: Andres
authors.initials: A
authors.lastname: Stricker
authors.affiliation: Center of Implantology, Periodontology and 3D Head- and Neck Diagnostics, Konstanz, Germany.|Oral Imaging Center, Faculty of Medicine, Katholieke Universiteit Leuven, Leuven, Belgium.
authors.forename: Jonathan
authors.initials: J
authors.lastname: Fleiner
authors.affiliation: Musculoskeletal Research Unit, Equine Hospital, Vetsuisse Faculty ZH, University of Zurich, Zurich, Switzerland.|Center of Applied Biotechnology and Molecular Medicine (CABMM), Vetsuisse Faculty, University of Zurich, Zurich, Switzerland.
authors.forename: Stefan
authors.initials: S
authors.lastname: Stübinger
authors.affiliation: Department of Oral and Maxillofacial Surgery, University Hospital of Freiburg, Freiburg, Germany.
authors.forename: Henrik
authors.initials: H
authors.lastname: Fleiner
authors.affiliation: Department of Oral Surgery and Stomatology, School of Dental Medicine, University of Bern, Bern, Switzerland.
authors.forename: Daniel
authors.initials: D
authors.lastname: Buser
authors.affiliation: Department of Oral Surgery and Stomatology, School of Dental Medicine, University of Bern, Bern, Switzerland.|Robert K. Schenk Laboratory of Oral Histology, School of Dental Medicine, University of Bern, Bern, Switzerland.|Department of Periodontology, School of Dental Medicine, University of Bern, Bern, Switzerland.
authors.forename: Dieter D
authors.initials: DD
authors.lastname: Bosshardt
mesh_terms: D000540:Alveolar Ridge Augmentation / Q000379:methods*; D000818:Animals; D001861:Bone Regeneration / Q000502:physiology*; D003094:Collagen; D003758:Dental Implantation, Endosseous; D015921:Dental Implants; D006882:Hydroxyapatites / Q000494:pharmacology; D008334:Mandible / Q000601:surgery; D013524:Surgical Flaps; D013552:Swine; D013556:Swine, Miniature; D014025:Titanium; D014081:Tooth Extraction; D014945:Wound Healing / Q000502:physiology
chemical_list: C106416:Bio-Gide; D015921:Dental Implants; D006882:Hydroxyapatites; C074950:hydroxyapatite-beta tricalcium phosphate; D003094:Collagen; D014025:Titanium
keywords: bone splitting/ridge expansion; guided bone regeneration; miniature pig; osseointegration; ridge preservation