title: Preliminary report on a staged ridge splitting technique for implant placement in the mandible: a technical note.
abstract: OBJECTIVE
  Narrow edentulous alveolar ridges less than 5 mm wide require horizontal augmentation for the placement of screw-type dental implants. A staged approach to ridge splitting in the mandible to decrease the risk of malfracture during osteotomy is presented.
  
  
  METHODS
  Five consecutive patients with 6 long-span edentulous areas of the mandibular ridge were included in this study. After corticotomy of a rectangular buccal segment and a 40-day healing period, the mandibular ridge was split, leaving the buccal periosteum attached to the lateralized segment. Seventeen dental implants were placed, and the gap between the implants and the bone filled with a mixture of venous blood and a porous algae-derived hydroxyapatite.
  
  
  RESULTS
  All buccal segments fractured as planned at the basal corticotomy during ridge splitting. After 6 months, all implants were stable and surrounded by bone; prosthetic loading with fixed partial dentures was successful in all cases.
  
  
  CONCLUSIONS
  In the mandible, greenstick fracture during widening with osteotomes has not been controllable to date because of cortical thickness of the bone; the risk of malfracture during single-stage ridge splitting was high. With this approach, the location of the greenstick fracture is predetermined, and the perfusion for the buccal segment remains intact, although vascularization shifts from internal perfusion from spongy bone after the first intervention to external perfusion from the periosteum after the second intervention. The buccal cortical segment remains a pedicled graft after ridge splitting.
  
  
  CONCLUSIONS
  The preliminary results of this report indicate that staged ridge splitting can be a safe technique which overcomes the problems associated with single-stage ridge expansion/ridge splitting procedures without causing significant delay in treatment.
authors.affiliation: University-Clinic for Oral and Maxillofacial Surgery, Medical University Vienna, Vienna, Austria. georg.enislidis@meduniwien.ac.at
authors.forename: Georg
authors.initials: G
authors.lastname: Enislidis
authors.forename: Gerd
authors.initials: G
authors.lastname: Wittwer
authors.forename: Rolf
authors.initials: R
authors.lastname: Ewers
mesh_terms: D000293:Adolescent; D000328:Adult; D000539:Alveolar Process / Q000000981:diagnostic imaging / Q000601:surgery*; D016025:Bone Transplantation / Q000379:methods; D003758:Dental Implantation, Endosseous / Q000379:methods*; D005260:Female; D006801:Humans; D007576:Jaw, Edentulous, Partially / Q000601:surgery*; D008297:Male; D008334:Mandible / Q000601:surgery; D008875:Middle Aged; D011446:Prospective Studies; D011859:Radiography; D016474:Weight-Bearing