Clinical, histological and histomorphometric evaluation of the healing of mandibular ramus bone block grafts for alveolar ridge augmentation before implant placement.
BACKGROUND
Localized bone defects in the maxilla are commonly reconstructed with autologous mono-cortical bone blocks prior to the placement of dental implants. This study presents a clinical, histological and histomorphometric analysis on the use of mandibular ramus block grafts for ridge augmentation.


METHODS
mono-cortical bone blocks from the mandibular ramus were grafted in 15 patients. The bone grafts were left to heal for period varying from 3 to 9 months. Afterwards, 30 implants were inserted and bone samples were removed for subsequent histological analysis.


RESULTS
All the bone grafts were successful and resorption was minimal. There were no implant failures. At graft placement, mean lateral augmentation was 4.6+/-0.73mm, which, later, at the time of implant insertion, reduced to 4+/-0.77mm. Histological evaluation indicated signs of active remodelling in all specimens. However, the grafted bone contained substantial amounts of non-vital bone (NVB) and generally weak neo-vascularization regardless of the time of biopsies.


CONCLUSIONS
The outcome of the study suggests that the larger part of osteocytes in mono-cortical bone do not survive grafting and neo-vascularization of non-vital grafted bone is difficult because of the slow remodelling process into new vital.
Acocella
Alessandro
A
Department of Maxillo-Facial Surgery, Faculty of Medicine-University of Florence, Italy.
Bertolai
Roberto
R
Colafranceschi
Maurizio
M
Sacco
Roberto
R
D000328:Adult; D000368:Aged; D016301:Alveolar Bone Loss / Q000601:surgery; D000540:Alveolar Ridge Augmentation / Q000379:methods*; D016723:Bone Remodeling; D016025:Bone Transplantation / Q000379:methods / Q000502:physiology*; D016923:Cell Death; D003758:Dental Implantation, Endosseous; D005260:Female; D006085:Graft Survival / Q000502:physiology*; D006801:Humans; D016018:Least-Squares Analysis; D008297:Male; D008334:Mandible / Q000098:blood supply / Q000601:surgery*; D008437:Maxilla / Q000098:blood supply / Q000601:surgery*; D008439:Maxillary Diseases / Q000601:surgery; D008875:Middle Aged; D018919:Neovascularization, Physiologic; D010011:Osteocytes / Q000166:cytology; D020858:Tissue and Organ Harvesting / Q000379:methods; D014945:Wound Healing; D055815:Young Adult