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Updated: Feb 8, 2026

Author Spotlight: The Box-Cavity Cortical Approach for Enhanced Evaluation of Biomaterials and Bone Regeneration
Published on: November 21, 2023
Guided bone regeneration using a hydrophilic membrane made of unsintered hydroxyapatite and poly(L-lactic acid) in a
Reo Ikumi1, Takayuki Miyahara1, Norio Akino1
1Department of Oral Implantology and Regenerative Dental Medicine, Tokyo Medical and Dental University.
Abstract:
The effectiveness of a previously developed unsintered hydroxyapatite (uHA) and poly(L-lactic acid) (PLLA) hydrophilic membrane as a resorbable barrier for guided bone regeneration (GBR) was evaluated. Critical-size 8-mm diameter bone defects were surgically generated in the parietal bones of 24 12-week-old male Wistar rats, which were then divided into three groups in which either a uHA/PLLA or a collagen membrane or no membrane (control) was placed onto the bone defect. Following sacrifice of the animals 2 or 4 weeks after surgery, bone defects were examined using microcomputed tomography and histological analysis. Bone mineral density, bone mineral content, and relative bone growth area values 2 or 4 weeks after surgery were highest in the uHA/PLLA group. Four weeks after surgery, the relative bone growth area in the uHA/PLLA group was larger than that in the collagen group. The resorbable uHA/PLLA membrane is thus potentially effective for GBR.
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