1Resolutions of thickened maxillary sinus mucosa corresponding to molars with severe periodontal lesions using minimally invasive extraction and site preservation: a case analysisXU Tao, ZHANG Bo, HAN Zi-yao, HU Wen-jie, LIU Yun-songSPECIAL COLUMN FOR IMPLANT RESTORATION ASSISTED BY SOFT AND HARD TISSUE INCREMENTAL TECHNOLOGY577-5832Guided bone regeneration with tenting screw technology in immediate implant placement of mandibular anterior teeth: a case analysisWEI Yi-ping, ZHEN Min, ZHAO Li-ping, HU Wen-jie, LIU Yun-songSPECIAL COLUMN FOR IMPLANT RESTORATION ASSISTED BY SOFT AND HARD TISSUE INCREMENTAL TECHNOLOGY584-588,5933Guided bone regeneration combined with free gingival graft to redevelop surgical site of a failed implant for another implant replacementSUN Fei, WANG Cui, XU Tao, HU Wen-jie, LIU Yun-songSPECIAL COLUMN FOR IMPLANT RESTORATION ASSISTED BY SOFT AND HARD TISSUE INCREMENTAL TECHNOLOGY589-5934Free gingival grafts increasing keratinized tissue to improve soft tissue conditions around implants for health maintenance: a case analysis with 2 years of follow-upLI Li-man, YANG Gang, HU Wen-jieSPECIAL COLUMN FOR IMPLANT RESTORATION ASSISTED BY SOFT AND HARD TISSUE INCREMENTAL TECHNOLOGY594-5995Study of the effect of machinable resin ceramic composite materials on the eruption and occlusion of the molars of the adolescent patientsSUN Hao, XING Wen-zhongORIGINAL CONTRIBUTIONS608-6116Investigation on the relationship between gene polymorphism of interleukin-6 and peri-implant diseasesGAO Juan-juan, LUO Yan-yan, SUN Xiao-ju, XIE Hong, DENG WeiORIGINAL CONTRIBUTIONS612-6167Research progress in the mechanism of Porphyromonas gingivalis in promoting oral squamous cell cancerLU Ze, PAN Ya-pingREVIEW617-6218Research progress on the relationship between periodontal disease and chronic kidney diseaseZHOU Wan-hang, LI Yan-fei, GUO Liu-yun, XU Ri-cong, WAN Qi-junREVIEW622-627 