title: Bone regenerative effect of recombinant human bone morphogenetic protein-2 after cyst enucleation.
abstract: BACKGROUND
  The aim of this study is to quantitatively evaluate the effect of rhBMP-2 for repair of bone defects after cyst enucleation using the osteogenesis index (OI).
  
  
  METHODS
  Under general anesthesia, 10 patients (12 lesions) underwent oral or maxillofacial surgery for cyst enucleation. Postoperatively, 12 lesions were divided into two groups: group A (six lesions) was treated with absorbable collagen sponge (ACS) in combination with rhBMP-2, and group B (six lesions) was treated with ACS alone. After 3 months, cone-beam computed tomographic scans were obtained to measure changes in the volume of the lesions. We then calculated the OI of each group at two different Hounsfield units to determine any statistically significant difference between these two groups (Mann-WhitneyUtest).
  
  
  RESULTS
  As tested at the level of new bone, the mean OI was 72.37 % in group A and 55.08 % in group B -a statistically significant difference (p= 0.041). As tested at the level of mature bone, the mean OI was 27.47 % in group A and 18.88 % in group B, but the difference was not statistically significant (p= 0.394).
  
  
  CONCLUSIONS
  The application of rhBMP-2 after maxillofacial cyst enucleation accelerated new bone formation in the bone defects. Thus, the use of rhBMP-2 in combination with ACS may be considered an alternative to conventional bone grafting in some patients with postoperative bone defects.
authors.affiliation: Department of Oral and Maxillofacial Surgery, Institute of Oral Health Science, Ajou University School of Medicine, 164, World Cup-ro, Yeongtong-gu, Suwon-si, Gyeonggi-do 16499 Republic of Korea.
authors.forename: Doo Yeon
authors.initials: DY
authors.lastname: Hwang
authors.affiliation: Department of Oral and Maxillofacial Surgery, Institute of Oral Health Science, Ajou University School of Medicine, 164, World Cup-ro, Yeongtong-gu, Suwon-si, Gyeonggi-do 16499 Republic of Korea.
authors.forename: Sung Woon
authors.initials: SW
authors.lastname: On
authors.affiliation: Department of Oral and Maxillofacial Surgery, Institute of Oral Health Science, Ajou University School of Medicine, 164, World Cup-ro, Yeongtong-gu, Suwon-si, Gyeonggi-do 16499 Republic of Korea.
authors.forename: Seung Ii
authors.initials: SI
authors.lastname: Song
keywords: Bone defect; Bone regeneration; rhBMP-2