Three-dimensional evaluation of upper anterior alveolar bone dehiscence after incisor retraction and intrusion in adult patients with bimaxillary protrusion malocclusion  

作　　者：Qing-yuan GUO Shi-jie ZHANG Hong LIU Chun-ling WANG Fu-lan WEI Tao LV Na-na WANG Dong-xu LIU 

机构地区：[1]Department of Orthodontics, Shandong Provincial Key Laboratory of Oral Biomedicine, Shandong University, Jinan 250012, China [2]Department of Stomatology, the Second Hospital of Shandong University, Jinan 250033, China

出　　处：《Journal of Zhejiang University-Science B(Biomedicine & Biotechnology)》2011年第12期990-997,共8页浙江大学学报（英文版）B辑（生物医学与生物技术）

基　　金：Project supported by the Shandong Science and Technology Planning Project Contract Research (Nos. 2008GG30002019 and 2008GG 30001001) of China;the Shandong University Dental School Project Research (Nos. P2009009,P2009010,and P2010010),China

摘　　要：Objective:The purpose of this study was to evaluate three-dimensional(3D) dehiscence of upper anterior alveolar bone during incisor retraction and intrusion in adult patients with maximum anchorage.Methods:Twenty adult patients with bimaxillary dentoalveolar protrusion had the four first premolars extracted.Miniscrews were placed to provide maximum anchorage for upper incisor retraction and intrusion.A computed tomography(CT) scan was performed after placement of the miniscrews and treatment.The 3D reconstructions of pre-and post-CT data were used to assess the dehiscence of upper anterior alveolar bone.Results:The amounts of upper incisor retraction at the edge and apex were(7.64±1.68) and(3.91±2.10) mm,respectively,and(1.34±0.74) mm of upper central incisor intrusion.Upper alveolar bone height losses at labial alveolar ridge crest(LAC) and palatal alveolar ridge crest(PAC) were 0.543 and 2.612 mm,respectively,and the percentages were(6.49±3.54)% and(27.42±9.77)%,respectively.The shape deformations of LAC-labial cortex bending point(LBP) and PAC-palatal cortex bending point(PBP) were(15.37±5.20)° and(6.43±3.27)°,respectively.Conclusions:Thus,for adult patients with bimaxillary protrusion,mechanobiological response of anterior alveolus should be taken into account during incisor retraction and intrusion.Pursuit of maximum anchorage might lead to upper anterior alveolar bone loss.Objective：The purpose of this study was to evaluate three-dimensional（3D） dehiscence of upper anterior alveolar bone during incisor retraction and intrusion in adult patients with maximum anchorage.Methods：Twenty adult patients with bimaxillary dentoalveolar protrusion had the four first premolars extracted.Miniscrews were placed to provide maximum anchorage for upper incisor retraction and intrusion.A computed tomography（CT） scan was performed after placement of the miniscrews and treatment.The 3D reconstructions of pre-and post-CT data were used to assess the dehiscence of upper anterior alveolar bone.Results：The amounts of upper incisor retraction at the edge and apex were（7.64±1.68） and（3.91±2.10） mm,respectively,and（1.34±0.74） mm of upper central incisor intrusion.Upper alveolar bone height losses at labial alveolar ridge crest（LAC） and palatal alveolar ridge crest（PAC） were 0.543 and 2.612 mm,respectively,and the percentages were（6.49±3.54）% and（27.42±9.77）%,respectively.The shape deformations of LAC-labial cortex bending point（LBP） and PAC-palatal cortex bending point（PBP） were（15.37±5.20）° and（6.43±3.27）°,respectively.Conclusions：Thus,for adult patients with bimaxillary protrusion,mechanobiological response of anterior alveolus should be taken into account during incisor retraction and intrusion.Pursuit of maximum anchorage might lead to upper anterior alveolar bone loss.

关 键 词：Alveolar bone loss Adult patients Computed tomography Three-dimensional registration 

分 类 号：R783.5[医药卫生—口腔医学]