Bone regeneration enhancement by ultra-violet (UV) treatment for uHA/PLLA absorbable mesh.
OBJECTIVE
The purpose of this study was to evaluate the effect of bone regeneration enhancement by ultra-violet (UV) treatment of an unsintered hydroxyapatite (u-HA)/poly-l-lactic acid (PLLA) mesh in rabbitnasal bone.


METHODS
Thirty adult male Japanese white rabbits (12-16 weeks, 2.5-3.0 kg) were used in this study. After incising along the nasal bone, 6 × 6 × depth 1 mm two bone defects were made on both sides. In the UV group (n = 30), the defects were covered with uHA/PLLA mesh, treated by UV (wavelength 172 nm, tube wall illumination 13 mW/cm2, period 8 min, intensity 6.26 J/cm2) and screwed. In the control group (n = 30), untreated uHA/PLLA was applied in a similar manner. The rabbits were sacrificed at 1, 2, 3, 4 and 6 weeks postoperatively, and formalin-fixed specimens were frozen. The specimens were stained with haematoxylin and eosin. For immunohistochemical analysis, the specimens were treated with anti-alkaline phosphatase (ALP). Finally, bone ratio and ALP expression were evaluated microscopically.


RESULTS
The UV group had a significantly higher number of ALP stained cells than the control group after 1, 2, and 3 weeks (P < 0.05). The bone ratio was also significantly higher in the UV group than in the control group after 1, 2, 3, and 4 weeks (P < 0.05).


CONCLUSIONS
This study suggests that bone regeneration can be enhanced by UV treatment using an uHA/PLLA mesh.
Department of Oral & Maxillofacial Surgery (Chief Professor: Koichiro Ueki), Division of Medicine, Interdisciplinary Graduate School of Medicine and Engineering, University of Yamanashi, 1110 Shimokato, Chuo, Yamanashi, Japan.
Hiroumi
H
Ikawa
Department of Oral & Maxillofacial Surgery (Chief Professor: Koichiro Ueki), Division of Medicine, Interdisciplinary Graduate School of Medicine and Engineering, University of Yamanashi, 1110 Shimokato, Chuo, Yamanashi, Japan. Electronic address: amoroi@yamanashi.ac.jp.
Akinori
A
Moroi
Department of Oral & Maxillofacial Surgery (Chief Professor: Koichiro Ueki), Division of Medicine, Interdisciplinary Graduate School of Medicine and Engineering, University of Yamanashi, 1110 Shimokato, Chuo, Yamanashi, Japan.
Kunio
K
Yoshizawa
Department of Oral & Maxillofacial Surgery (Chief Professor: Koichiro Ueki), Division of Medicine, Interdisciplinary Graduate School of Medicine and Engineering, University of Yamanashi, 1110 Shimokato, Chuo, Yamanashi, Japan.
Yuriko
Y
Saida
Department of Oral & Maxillofacial Surgery (Chief Professor: Koichiro Ueki), Division of Medicine, Interdisciplinary Graduate School of Medicine and Engineering, University of Yamanashi, 1110 Shimokato, Chuo, Yamanashi, Japan.
Asami
A
Hotta
Department of Oral & Maxillofacial Surgery (Chief Professor: Koichiro Ueki), Division of Medicine, Interdisciplinary Graduate School of Medicine and Engineering, University of Yamanashi, 1110 Shimokato, Chuo, Yamanashi, Japan.
Takamitsu
T
Tsutsui
Department of Oral & Maxillofacial Surgery (Chief Professor: Koichiro Ueki), Division of Medicine, Interdisciplinary Graduate School of Medicine and Engineering, University of Yamanashi, 1110 Shimokato, Chuo, Yamanashi, Japan.
Kenichi
K
Fukaya
Department of Oral & Maxillofacial Surgery (Chief Professor: Koichiro Ueki), Division of Medicine, Interdisciplinary Graduate School of Medicine and Engineering, University of Yamanashi, 1110 Shimokato, Chuo, Yamanashi, Japan.
Ryota
R
Hiraide
Department of Oral & Maxillofacial Surgery (Chief Professor: Koichiro Ueki), Division of Medicine, Interdisciplinary Graduate School of Medicine and Engineering, University of Yamanashi, 1110 Shimokato, Chuo, Yamanashi, Japan.
Akihiro
A
Takayama
Department of Oral & Maxillofacial Surgery (Chief Professor: Koichiro Ueki), Division of Medicine, Interdisciplinary Graduate School of Medicine and Engineering, University of Yamanashi, 1110 Shimokato, Chuo, Yamanashi, Japan.
Tatsuya
T
Tsunoda
Department of Oral & Maxillofacial Surgery (Chief Professor: Koichiro Ueki), Division of Medicine, Interdisciplinary Graduate School of Medicine and Engineering, University of Yamanashi, 1110 Shimokato, Chuo, Yamanashi, Japan.
Yuki
Y
Saito
Department of Oral & Maxillofacial Surgery (Chief Professor: Koichiro Ueki), Division of Medicine, Interdisciplinary Graduate School of Medicine and Engineering, University of Yamanashi, 1110 Shimokato, Chuo, Yamanashi, Japan.
Koichiro
K
Ueki
D000818:Animals; D001861:Bone Regeneration / Q000528:radiation effects*; D017886:Durapatite / Q000627:therapeutic use*; D008297:Male; D009295:Nasal Bone / Q000502:physiology; D011091:Polyesters / Q000627:therapeutic use*; D011817:Rabbits; D013526:Surgical Mesh; D014466:Ultraviolet Rays
D011091:Polyesters; C499699:hydroxyapatite-polylactide; D017886:Durapatite
Absorbable mesh; Bone regeneration; Ultra-violet; uHA/PLLA