title: [Guided bone regeneration at a dehiscence-type defect using chitosan/collagen membranes in dogs].
abstract: OBJECTIVE
  To compare a developed absorbable chitosan/collagen membrane (CCM) with a standard biodegradable collagen membrane for the treatment of implant dehiscence-type defect in dog model.
  
  
  METHODS
  The right four mandibular premolars and the first molar were extracted in each of 10 beagle dogs.Four months later, acute buccal dehiscence-type defects were surgically created following implant site preparation in each dog. Using self-control, defects were randomly assigned to four different groups: CCM-1 (with the ratio of chitosan and collagen of 40: 1), CCM-2(with the ratio of chitosan and collagen of 20: 1), Bio-Gide collagen membrane (BG collagen), control. The animals were sacrificed after 4 (3 animals), 8 (3 animals) and 12 (4 animals) weeks of healing interval for histological observation and histomorphometrical analysis including defect length (DL), new bone height (NBH), bone-to-implant contact (BIC) and area of new bone fill (BA).
  
  
  RESULTS
  Newly formed bone was observed in all the groups and became mature with time. At 8 weeks, increased mean NBH and BIC values were obtained for all the groups, the mean NBH values of the CCM-1, CCM-2 and BG groups [( 1.1 0 ± 0.11)∼(1.48 ± 0.07) mm]were significantly higher than that of the control [(0.74 ± 0.12) mm] (P < 0.05). At 12 weeks, the membranes treated groups obtained more mean NBH,BIC and BA values compared with the control. The CCM-1 groups showed the highest mean NBH value [(1.91 ± 0.25) mm], which was significantly higher than the control [(1.20 ± 0.34) mm](P < 0.05).However, no statistically significant differences in BIC and BA were found between membrane groups and control and among the membranes treated groups.
  
  
  CONCLUSIONS
  The results of this study demonstrated that the developed CCM can enhance bone regeneration and obtaine similar amounts of newly formed bone compared with defects regenerated with a standard collagen membrane.
authors: Department of Prosthodontics, The Second Affiliated Hospital, College of Medicine, Zhejiang University, Hangzhou 310009, China.
authors: Xiaojing
authors: X
authors: Li
authors: Xinmu
authors: X
authors: Wang
authors: Yuwen
authors: Y
authors: Miao
authors: Guoli
authors: G
authors: Yang
authors: Bo
authors: B
authors: Gao
authors: Email: yandong_66@163.com.
authors: Yan
authors: Y
authors: Dong
mesh_terms: D000818:Animals; D001861:Bone Regeneration; D048271:Chitosan; D003094:Collagen; D003758:Dental Implantation, Endosseous; D004285:Dogs; D008567:Membranes, Artificial; D013529:Surgical Wound Dehiscence; D014081:Tooth Extraction; D014945:Wound Healing
chemical_list: C106416:Bio-Gide; D008567:Membranes, Artificial; D003094:Collagen; D048271:Chitosan