title: Effect of hyaluronic acid on bone formation in the expanded interpremaxillary suture in rats.
abstract: OBJECTIVE
  To evaluate the histomorphometric effects of different molecular weight hyaluronic acid on bone formation in rats after expansion of the interpremaxillary suture.
  
  
  METHODS
  Twenty-four male Sprague Dawley rats were divided into three groups. Each group was subjected to expansion for 5 days and retention for 10 days. Group 1 received 50 μl of high molecular weight hyaluronic acid (HMWHA), group 2 received 50 μl of low molecular weight hyaluronic acid (LMWHA), and the control group received same amount of saline solution to the interpremaxillary suture. Ten days after injection, the rats were killed and their maxillas dissected. For the histomorphometric evaluation, blocks were serially sectioned at 10-μm intervals. Sections were stained with hematoxylin-eosin (HE) and evaluated with image analysis software. Bone area (μm²) (BA), bone perimeter of suture borders (μm) (BP), and ratio of osteoblast cells and capillary cells to BA and BP parameters were evaluated.
  
  
  RESULTS
  HMWHA showed a statistically higher ratio of osteoblast and capillary cell scores compared with the LMWHA and control groups (p < 0.05). There were no statistically significant differences in between LMWHA and control groups (p > 0.05).
  
  
  CONCLUSIONS
  Local injection of HMWHA in the interpremaxillary suture after rapid maxillary expansion stimulated new bone formation, which may shorten the retention period and may reduce the risk of relapse. LMWHA has no effect on bone formation in interpremaxillary suture.
authors.affiliation: Department of Orthodontics, Faculty of Dentistry, Yeditepe University, Istanbul, Turkey.
authors.forename: T B
authors.initials: TB
authors.lastname: Sadikoglu
authors.affiliation: Department of Orthodontics, Faculty of Dentistry, Yeditepe University, Istanbul, Turkey.
authors.forename: D
authors.initials: D
authors.lastname: Nalbantgil
authors.affiliation: Department of Orthodontics, Faculty of Dentistry, Yeditepe University, Istanbul, Turkey.
authors.forename: F
authors.initials: F
authors.lastname: Ulkur
authors.affiliation: Department of Histology, Faculty of Medicine, Medipol University, Istanbul, Turkey.
authors.forename: N
authors.initials: N
authors.lastname: Ulas
mesh_terms: D000818:Animals; D002196:Capillaries / Q000033:anatomy & histology / Q000187:drug effects / Q000254:growth & development; D003393:Cranial Sutures / Q000033:anatomy & histology / Q000187:drug effects* / Q000254:growth & development*; D042783:Endothelial Cells / Q000187:drug effects; D006820:Hyaluronic Acid / Q000494:pharmacology* / Q000627:therapeutic use; D008297:Male; D008437:Maxilla / Q000187:drug effects; D010006:Osteoblasts / Q000187:drug effects; D010012:Osteogenesis / Q000187:drug effects*; D010155:Palatal Expansion Technique; D011897:Random Allocation; D051381:Rats; D017207:Rats, Sprague-Dawley
chemical_list: D006820:Hyaluronic Acid
keywords: histomorphometry; hyaluronic acid; maxillary expansion; orthodontics; rat