Jumping Gap Bone Grafting Fails To Prevent Horizontal Bone Resorption

This study aimed to observe whether jumping gap bone grafting during immediate implantation with thin (< 1mm) or thick (> 1mm) buccal plates in CBCT images can prevent horizontal bone resorption. This retrospective cohort study (Ethics No.20200713001; ChiCTR2400087290) analyzed 72 patients (80 implants) undergoing immediate implant in the maxillary premolar area, with bone grafting in the jumping gap based on patient preference. Patients were stratified into four groups: thin/grafting (n=17), thin/non-grafting (n=26), thick/grafting (n=17), and thick/non-grafting (n=20). Buccal bone width of the implant was assessed at three standardized levels (shoulder, middle and apex of the implant) immediately post-surgery and 1 year after functional loading in CBCT images. Horizontal bone resorption was analyzed using non-parametric statistical methods (Mann-Whitney U). Maximum horizontal bone resorption occurred at the implant shoulder in all groups. And there was no significant difference in horizontal bone resorption between thin/grafting (1.1±0.3 mm) and thin/non-grafting (1.1±0.4 mm) groups (p=0.990) and thick/grafting ( 0.5±0.2 mm) and thick/non-grafting (0.7±0.2 mm) groups (p=0.103). However, horizontal bone resorption in the two thin plate groups were higher than that in the two thick plate groups (p=0.001, grafting, and p=0.001,non-grafting), respectively. Jumping gap grafting does not reduce horizontal bone resorption regardless of buccal bone thickness, but thicker bone plates better maintain post-implant buccal bone width.