Cirugia Mucogingival

Allogeneic Bone Onlay Grafts for Alveolar Ridge
Augmentation: A Systematic Review
Jonathan Waasdorp, DMD1/Mark A. Reynolds, DDS, PhD2

Purpose: This systematic review examines the published findings on the clinical effectiveness and predictability of allogeneic bone blocks for the correction of alveolar ridge deformities to support dental
implant placement in humans. Materials and Methods: Abibliographic search was conducted of the
MEDLINE and EMBASE databases for studies in which allogeneic block grafts were used for alveolar
bone augmentation. The search was limited to human studies in English-language publications
between 1950 and September 2008. Data extraction included the following outcomes: (1) vertical
and/or horizontal bone gain/loss, (2) graft failure rate andcomplications, and (3) implant survival rate.
Results: The initial search identified 35 papers from the electronic databases, with nine publications
meeting inclusion criteria: two case reports, six case series, and one prospective, multicenter, consecutive case series. No randomized controlled clinical trials were identified in the search. Observational
studies (110 total patients) generally reportedhigh rates of clinical graft incorporation (90% or greater)
and implant survival (99% to 100%); however, the majority of reports involved selected defects in anterior regions with short-term follow-up (less than 3 years). Conclusion: Clinical evidence remains limited
to case series and reports that differ with respect to alveolar ridge defect selection, treatment, and
endpoints of therapy overshort-term follow-up periods. Although case-based reports document the
potential for allogeneic block grafts to support alveolar ridge augmentation and implant placement, insufficient evidence is available to establish treatment efficacy relative to graft incorporation, alveolar ridge
augmentation, and long-term dental implant survival. INT J ORAL MAXILLOFAC IMPLANTS 2010;25:525–531
Key words:allograft, alveolar ridge, augmentation, bone, dental implant, onlay grafting

lveolar ridge augmentation is often a prerequisite
for optimal placement of endosseous implants
for prosthetic rehabilitation. Clinical evidence supports the use of vertical and lateral ridge augmentation procedures to enable dental implant
placement,1,2 with autogenous grafts widely considered the gold standardfor the predictable correction
of severe localized ridge deformities.3 In contrast to
particulate autogenous grafts, which require additional materials to ensure space maintenance and

A

1Senior

Resident, Department of Periodontics, University of
Maryland, Dental School, Baltimore, Maryland.
2Chair and Director, Postdoctoral Periodontics, Department of
Periodontics, University ofMaryland, Dental School, Baltimore,
Maryland.
Correspondence to: Dr Mark Reynolds, Department of Periodontics,
University of Maryland, Dental School, 650 West Baltimore Street,
Baltimore, MD 21201. Email: mreynolds@umaryland.edu

graft containment, such as barrier membranes, tenting screws, and/or graft binders, onlay grafts are selfcontained and provide an inherent ability to support
the softtissue.
Constraints in the size of autogenous block grafts
from intraoral sites and the morbidity associated with
graft harvesting often limit treatment recommendations and patient acceptance in practice. Complications associated with block grafts harvested from the
symphysis or retromolar area, for example, can
include nerve injury, soft tissue injury, wound dehiscence, and infection.4,5Allogeneic block grafts, in contrast, lack many of the donor site limitations of
autogenous block grafts. Allograft bone also permits
the selection of blocks with a predefined configuration and corticocancellous composition.
Case reports document the successful clinical use
of fresh-frozen allogeneic onlay grafts for ridge augmentation6–8; however, because of concerns related
to disease...