Histomorphometric comparison of maxillary pristine bone and composite bone graft biopsies obtained after sinus augmentation.
BACKGROUND
Sinus grafting is a technique oriented to facilitate implant placement in posterior atrophic maxillae. Several modifications of the original technique and a wide variety of materials have been proposed; most of them associated with implant survival rates. However, the quality of the bone obtained after the application of certain grafting materials has not been fully elucidated yet. The aims of this multicenter study were to analyse histomorphometrical samples obtained 6 months after sinus grafting using a composite graft consisting of anorganic bovine bone (ABB)+ autologous bone (AB), and to compare these samples with maxillary pristine bone biopsies.


METHODS
Ninety maxillary sinus augmentations were performed for delayed implant placement (N = 90) in 45 consecutive patients (test group). Bone cores were harvested 6 months after grafting for histomorphometric and ultrastructural study. Control pristine bone biopsies were taken from the posterior maxilla of 10 patients (control). Bone radiographic changes were assessed up to 24 months after implant loading.


RESULTS
The total mean values after analysis of test cores revealed a proportion of 46.08 + or - 16.6% of vital bone, 42.27 + or - 15.1% of non-mineralized connective tissue, and 37.02 + or - 25.1% of the remaining ABB particles. Significant bone remodeling activities were noticed in sinus grafting samples when compared with pristine bone. A statistically significant difference was observed in the number of osteoid lines between two groups, with higher values in the test one (15.1 + or - 11.48% vs. 2.5 + or - 2.2%, P = 0.0005). Ultrastructural study showed that vital trabecular bone was in intimal contact with ABB particles. Radiographic analysis revealed that the higher the proportion of remaining ABB, the lower the total vertical resorption of the graft.


CONCLUSIONS
Sinus grafting constitutes an excellent model for the study of de novo bone formation patterns and graft consolidation, when a combination of different bone substitutes is applied. The combination of ABB+AB yields highly satisfactory outcomes from both a clinical and a histologic perspective.
Oral Surgery and Implant Dentistry Department, School of Dentistry, University of Granada, Granada, Spain. pgalindo@ugr.es
Pablo
P
Galindo-Moreno
Ildefonso
I
Moreno-Riestra
Gustavo
G
Avila
Juan Emilio
JE
Fernández-Barbero
Francisco
F
Mesa
Mariano
M
Aguilar
Hom-Lay
HL
Wang
Francisco
F
O'Valle
D000328:Adult; D000368:Aged; D000540:Alveolar Ridge Augmentation / Q000379:methods*; D000818:Animals; D001672:Biocompatible Materials / Q000494:pharmacology; D001706:Biopsy; D001857:Bone Matrix / Q000637:transplantation; D018786:Bone Substitutes / Q000494:pharmacology*; D016025:Bone Transplantation / Q000379:methods*; D002417:Cattle; D003758:Dental Implantation, Endosseous; D005260:Female; D006801:Humans; D008297:Male; D008437:Maxilla / Q000000981:diagnostic imaging / Q000601:surgery / Q000648:ultrastructure; D008443:Maxillary Sinus / Q000000981:diagnostic imaging / Q000601:surgery*; D008875:Middle Aged; D016348:Osseointegration / Q000502:physiology*; D010012:Osteogenesis / Q000502:physiology; D011446:Prospective Studies; D011859:Radiography; D016896:Treatment Outcome
D001672:Biocompatible Materials; D018786:Bone Substitutes