Graft incorporation and implant osseointegration following the use of autologous and fresh-frozen allogeneic block bone grafts for lateral ridge augmentation.
OBJECTIVE
To compare autogenous bone (AT) and fresh-frozen allogeneic bone (AL) in terms of histomorphometrical graft incorporation and implant osseointegration after grafting for lateral ridge augmentation in humans.


METHODS
Thirty-four patients were treated with either AL (20 patients) or AT (14 patients) onlay grafts. During implant installation surgery 6 months after grafting, cylindrical biopsies were harvested perpendicularly to the lateral aspect of the augmented alveolar ridge. Additionally, titanium mini-implants were installed in the grafted regions, also perpendicularly to the ridge; these were biopsied during second-stage surgery. Histological/histomorphometric analysis was performed using decalcified and non-decalcified sections.


RESULTS
Histological analysis revealed areas of necrotic bone (NcB) occasionally in contact with or completely engulfed by newly formed vital bone (VB) in both AT and AL groups (55.9 ± 27.6 vs. 43.1 ± 20.3, respectively; P = 0.19). Statistically significant larger amounts of VB (27.6 ± 17.5 vs. 8.4 ± 4.9, respectively; P = 0.0002) and less soft connective tissue (ST) (16.4 ± 15.6 vs. 48.4 ± 18.1, respectively; P ≤ 0.0001) were seen for AT compared with AL. No significant differences were observed between the groups regarding both bone-to-implant contact (BIC) and the bone area between implant threads (BA) on the mini-implant biopsies.


CONCLUSIONS
Allogeneic bone block grafts may be an option in cases where a limited amount of augmentation is needed, and the future implant can be expected confined within the inner aspect of the bone block. However, the clinical impact of the relatively poor graft incorporation on the long-term performance of oral implants placed in AL grafts remains obscure.
Department of Periodontology, UNESP - University Estadual Paulista, Araraquara Dental School, Araraquara, São Paulo, Brazil; Department of Dentistry - Oral Radiology, Aarhus University, Aarhus, Denmark; Department of Dentistry - Periodontology, School of Dentistry, Aarhus University, Aarhus, Denmark.
Rubens
R
Spin-Neto
Andreas
A
Stavropoulos
Felipe Leite
FL
Coletti
Rafael Silveira
RS
Faeda
Luís Antônio Violin Dias
LA
Pereira
Elcio
E
Marcantonio
D000328:Adult; D000368:Aged; D000540:Alveolar Ridge Augmentation / Q000379:methods*; D001706:Biopsy; D016025:Bone Transplantation / Q000379:methods*; D003758:Dental Implantation, Endosseous; D015921:Dental Implants; D005260:Female; D006801:Humans; D008297:Male; D008875:Middle Aged; D016348:Osseointegration; D014182:Transplantation, Autologous; D014184:Transplantation, Homologous; D016896:Treatment Outcome
D015921:Dental Implants
autogenous bone; bone augmentation; fresh-frozen allogeneic bone; histology; human; osseointegration