1Free gingival graft increasing keratinized tissue to improve the conditions of implant restoration in molar sites :a case report with 3 years of follow-up.HAN Zi-yao, WANG Cui, HU Wen-jie, YANG Gang, LIU Yun-songSpecial Column for Multidisciplinary Treatment to Improve the Effect of Restoration and Implantation129-1352Intrusion of the overerupted molar to improve the space for implant restoration in mandibular molar region——a case report with 2.5 years of follow-upWANG An-qi, WANG Cui, HU Wen-jie, XUN Chun-lei, LIU Yun-songSpecial Column for Multidisciplinary Treatment to Improve the Effect of Restoration and Implantation136-1403Guided bone regeneration combined with connective tissue graft to improve the conditions of implant restoration for maxillary central incisor: a case report with 3 years of follow-upWEI Yi-ping, ZHEN Min, XU Tao, HU Wen-jie, LIU Yun-songSpecial Column for Multidisciplinary Treatment to Improve the Effect of Restoration and Implantation141-1454Multidisciplinary treatment for a patient with severe periodontitis combined by malocclusion of upper anterior teeth: a case report with 6-year follow-upZHANG Chuang-wei, HU Wen-jie, HU Wei, ZHANG Hao, LIANG Ling-zhiSpecial Column for Multidisciplinary Treatment to Improve the Effect of Restoration and Implantation146-1515Effects of platelet rich fibrin on biological properties of stem cells from apical papillaFU Yue, LEI Shuang, ZHU Shu, LIU Yao, CHEN XuORIGINAL CONTRIBUTIONS152-1576Study on the correlation between buccal corridor and craniomaxillofacial tissue structureXU Jing, PAN Yu, CHEN Yi-jiaORIGINAL CONTRIBUTIONS158-1617Alveolar bone thickness analysis of Angel Class Ⅱ division 1 and division 2 adult patients in upper incisor root apex regionLEI Qi, WANG Xiao-qinORIGINAL CONTRIBUTIONS166-1698Application effects of experiential oral hygiene instruction on simple gingivitis patientsGUO Qing-yuan, QIU Jing, ZHANG Juan, YANG Fang, ZHANG Yue, CHEN Zheng-gang, GUO Da-wei, YUAN Rong-tao, YU Jiang-boORIGINAL CONTRIBUTIONS170-1729Research progress in the correlation between periodontitis and inflammatory bowel diseaseLIU Dong-juan, PAN Ya-pingREVIEW173-177 