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Updated: Jan 22, 2026
Tri-layered Electrospinning to Mimic Native Arterial Architecture using Polycaprolactone, Elastin, and Collagen: A Preliminary Study
Published on: January 4, 2011
Horizontal ridge augmentation using GBR with a native collagen membrane and 1:1 ratio of particulate xenograft and
Silvio Mario Meloni1, Sascha Alexander Jovanovic2, Istvan Urban2,3
1School of Dentistry, University of Sassari, Sassari, Italy.
Background:
Cawood-Howell class IV atrophies, also known as "knife-edge" ridges, represent a serious horizontal defect, making the placement of regular implants challenging.
Aim:
To clinically and radiographically evaluate bone regeneration of severe horizontal bone defects with 3 years of follow-up.
Materials And Methods:
This study was designed as a single cohort, prospective clinical trial. Patients having horizontal bone width of 4 mm or less in the posterior mandible or maxilla were treated with resorbable collagen membranes and a 1:1 mixture of anorganic bovine bone (ABB) and autogenous bone. Implants were inserted and loaded 7 months later. Outcomes were implant and prosthetic survival rates, any biological and prosthetic complications, horizontal and volumetric bone dimensional changes measured on cone beam computer tomography (CBCT), peri-implant marginal bone level (MBL) changes measured on periapical radiographs, plaque index (PI), and bleeding on probing (BOP).
Results:
Eighteen patients received 55 implants. No patient dropped-out. No implant and prosthetic failures and no complications were recorded. Super imposition of pre and 7-month postoperative CBCT scans revealed an average horizontal bone gain of 5.03 ± 2.15 mm (95% CI: 4.13-5.92 mm). After 3 years, mean MBL was 1.15 ± 0.28 mm (95% CI 0.84-1.22 mm). The PI was 11.6%, and BOP was 5.2%.
Conclusion:
Within the limitations of the present study, high implant survival rate and high average bone augmentation seem to validate the use of collagen resorbable membranes with a 1:1 mixture of particulate ABB and autogenous bone for the reconstruction of Cawood-Howell class IV alveolar ridge atrophies.
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