title: Effect of deproteinized bovine bone matrix coverage on the resorption of iliac cortico-spongeous bone grafts - a prospective study of two cohorts.
abstract: OBJECTIVE
  The augmentation of the alveolar ridge using iliac cortico-spongeous bone grafts is routinely used. However, bone grafts show a substantial degree of resorption, which may negatively affect the long-term success of dental implants in the augmented area. The aim of this study was to evaluate the effect of a deproteinized bovine bone matrix coverage on the resorption of iliac bone grafts.
  
  
  METHODS
  Two cohorts consisting of 40 patients who received a vertical augmentation of the alveolar ridge with onlay grafts from the iliac crest were prospectively investigated over a period of 2 years. In half of the patients (n = 40), the grafts were covered by a thin layer of deproteinized bovine bone matrix (DBBM cohort). The other 40 patients received the identical surgical procedure without a DBBM coverage (non-DBBM cohort). The graft height/resorption was radiographically determined immediately after surgery, 6 months, 1 year, and 2 years postoperatively.
  
  
  RESULTS
  The height of the bone graft 6 months after surgery accounted 92.15% of the initial value in the DBBM cohort and 87.76% in the non-DBBM cohort. One year after augmentation, the height reduced to 83.95% in the DBBM cohort and 72.92% in the non-DBBM cohort. Two years after surgery, the resorption slowed down and the height of the grafts accounted 81.27% in the DBBM cohort and 71.43% in the non-DBBM cohort. The difference was statistically significant.
  
  
  CONCLUSIONS
  Deproteinized bovine bone matrix reduces the postoperative resorption of iliac bone block grafts and may therefore enhance the long-term implant prognosis in the augmented area.
authors.affiliation: Department of Oral & Maxillofacial Surgery, Christian-Albrechts-University, Kiel, Germany.
authors.forename: Jörg
authors.initials: J
authors.lastname: Wiltfang
authors.forename: Nadine
authors.initials: N
authors.lastname: Jätschmann
authors.forename: Jürgen
authors.initials: J
authors.lastname: Hedderich
authors.forename: Friedrich W
authors.initials: FW
authors.lastname: Neukam
authors.forename: Karl Andreas
authors.initials: KA
authors.lastname: Schlegel
authors.forename: Matthias
authors.initials: M
authors.lastname: Gierloff
mesh_terms: D000328:Adult; D000368:Aged; D000369:Aged, 80 and over; D000540:Alveolar Ridge Augmentation / Q000379:methods*; D000818:Animals; D001862:Bone Resorption; D016025:Bone Transplantation / Q000379:methods*; D002417:Cattle; D005260:Female; D006801:Humans; D007085:Ilium / Q000637:transplantation*; D008297:Male; D008875:Middle Aged; D008903:Minerals; D011446:Prospective Studies; D011862:Radiography, Panoramic; D016896:Treatment Outcome
chemical_list: C077540:Bio-Oss; D008903:Minerals