title: Comparison of two different absorbable membranes for the coverage of lateral osteotomy sites in maxillary sinus augmentation: a preliminary study.
abstract: BACKGROUND
  Barrier membranes, both absorbable and non-absorbable, have been used in sinus augmentation for many years. Some years ago, a new autologous blood substrate called Platelet-Rich-Fibrin (PRF) was introduced, and to date, the supporting effect on bone regeneration has been controversial. This study aimed to evaluate the effect of PRF on bone regeneration when used as a barrier membrane at the lateral osteotomy site in sinus augmentation.
  
  
  METHODS
  Twelve sinuses from six patients requiring bilateral sinus floor augmentation were treated with a two-stage surgical technique using sinus augmentation and implant placement after 5 months. The sinuses were grafted with autologous bone and bone-substitute material (Bio-Oss(®)) mixed in a 1:1 ratio and were covered in a randomized split-mouth design with a PRF or a conventional collagen membrane (Bio-Gide(®)), respectively. Five months later threaded titanium dental implants were inserted and bone specimens harvested with a trephine burr were evaluated histomorphometrically.
  
  
  RESULTS
  Bone quality seemed to be equal at both sites of the grafted sinuses. Mean vital bone formation after 5 months was 17.0% and 17.2%, for the PRF and collagen sites, respectively. The mean of residual bone-substitute was 15.9% and 17.3% for PRF and collagen, respectively. No local complications, such as dehiscences or membrane exposures, were detected at either site in any of the treated patients. After 12 months all implants reached primary stability in the augmented maxillary sinus floor without any peri-implant tissue inflammation.
  
  
  CONCLUSIONS
  Within the limits of the study the coverage of the lateral sinus window with two different absorbable membranes has been shown to result in a similar amount of vital bone formation and residual bone-substitute.
authors.affiliation: Department of Oral and Maxillofacial Surgery, University Hospital of Schleswig-Holstein, Campus Kiel, Kiel, Germany. gassling@mkg.uni-kiel.de
authors.forename: Volker
authors.initials: V
authors.lastname: Gassling
authors.forename: Nicolai
authors.initials: N
authors.lastname: Purcz
authors.forename: Jan-Hinrich
authors.initials: JH
authors.lastname: Braesen
authors.forename: Marcus
authors.initials: M
authors.lastname: Will
authors.forename: Matthias
authors.initials: M
authors.lastname: Gierloff
authors.forename: Eleonore
authors.initials: E
authors.lastname: Behrens
authors.forename: Yahya
authors.initials: Y
authors.lastname: Açil
authors.forename: Joerg
authors.initials: J
authors.lastname: Wiltfang
mesh_terms: D020341:Absorbable Implants; D000368:Aged; D001672:Biocompatible Materials / Q000737:chemistry; D001792:Blood Platelets / Q000502:physiology; D015519:Bone Density / Q000502:physiology; D001857:Bone Matrix / Q000637:transplantation; D001861:Bone Regeneration / Q000502:physiology; D018786:Bone Substitutes / Q000627:therapeutic use; D016025:Bone Transplantation / Q000379:methods; D003094:Collagen / Q000737:chemistry; D003758:Dental Implantation, Endosseous / Q000379:methods; D005337:Fibrin / Q000737:chemistry; D005500:Follow-Up Studies; D006801:Humans; D063166:Maxillary Osteotomy / Q000379:methods*; D008567:Membranes, Artificial; D008875:Middle Aged; D008903:Minerals / Q000627:therapeutic use; D016348:Osseointegration / Q000502:physiology; D010012:Osteogenesis / Q000502:physiology; D059546:Sinus Floor Augmentation / Q000379:methods*
chemical_list: C106416:Bio-Gide; C077540:Bio-Oss; D001672:Biocompatible Materials; D018786:Bone Substitutes; D008567:Membranes, Artificial; D008903:Minerals; D005337:Fibrin; D003094:Collagen