title: Atrophic maxillary floor augmentation by mineralized human bone allograft in sinuses of different size: an histologic and histomorphometric analysis.
abstract: OBJECTIVE
  The aims of this work were to histologically examine the healing of mineralized human bone allograft (MHBA) in sinus augmentation for elevating a severe maxillary atrophy ridge (≤2 mm residual ridge height) and to correlate the results to the sinus cavity size.
  
  
  METHODS
  A two-stage protocol was conducted in 23 patients, all having crestal bone ≤2 mm. A mixture of 80/20 cortical/cancellous of MHBA particles was used to augment sinus using the lateral window approach in narrow (NS; <15 mm bucco-palatal distance) and wide (WS; ≥15 mm bucco-palatal distance) sinuses, based upon computerized tomography (CT) assessment. A bone core biopsy was taken at implant placement, 6 and 9 months after surgery. Microradiography, histology and histochemistry of methacrylate-embedded sections were performed to analyze and to evaluate the bone and graft amount.
  
  
  RESULTS
  Newly formed bone around MBHA particles was found in all 28 biopsies. Bone showed a woven structure at 6 months after surgery and a lamellar structure 9 months after surgery. At 6 months after surgery, the 13 NS and 15 WS had 30.5±8.8% and 20.7±4.9% mean±SD bone formation, respectively. At 9 months after surgery, it was 38.8±7% (NS) and 30.7±3% (WS). Residual graft was about 16% (6 months) and 6% (9 months), in both NS and WS. The Mann-Whitney test showed a greater bone formation in NS than in WS (P<0.005).
  
  
  CONCLUSIONS
  The used 80/20 MHBA mixture appears to promote, in the severe atrophic maxilla, a satisfactory bone formation. Our results prove that the larger the sinus, the longer the maturation time needed to achieve a suitable amount of new bone formation.
authors.affiliation: Department of Anatomy and Histology, University of Modena and Reggio Emilia, Modena, Italy. davide.zaffe@unimore.it
authors.forename: Carlo Maria
authors.initials: CM
authors.lastname: Soardi
authors.forename: Sergio
authors.initials: S
authors.lastname: Spinato
authors.forename: Davide
authors.initials: D
authors.lastname: Zaffe
authors.forename: Hom-Lay
authors.initials: HL
authors.lastname: Wang
mesh_terms: D000328:Adult; D000368:Aged; D000540:Alveolar Ridge Augmentation / Q000379:methods*; D001284:Atrophy; D001706:Biopsy; D016025:Bone Transplantation / Q000379:methods* / Q000473:pathology; D002508:Cephalometry; D003758:Dental Implantation, Endosseous / Q000379:methods; D015921:Dental Implants; D005260:Female; D005500:Follow-Up Studies; D006085:Graft Survival; D006801:Humans; D007575:Jaw, Edentulous / Q000601:surgery; D007576:Jaw, Edentulous, Partially / Q000601:surgery; D008297:Male; D008437:Maxilla / Q000473:pathology / Q000601:surgery*; D008443:Maxillary Sinus / Q000473:pathology / Q000601:surgery*; D008567:Membranes, Artificial; D008852:Microradiography; D008875:Middle Aged; D010006:Osteoblasts / Q000473:pathology; D010011:Osteocytes / Q000473:pathology; D010012:Osteogenesis / Q000502:physiology; D010027:Osteotomy / Q000379:methods; D014057:Tomography, X-Ray Computed; D014184:Transplantation, Homologous
chemical_list: D015921:Dental Implants; D008567:Membranes, Artificial