Abstract: Objective To explore the factors affecting implant retention rate after mandibular reconstruction with fibula bone flap and provide theoretical direction for clinical therapy. Methods From January 2015 to December 2017, a total of 20 cases (male 12cases, female 8 cases,20 to 45 years old, average 27.2 years old) who received dental implantation after mandibular reconstruction were retrospectively analyzed. The data such as the status of keratinized gingiva, the thickness of peri-implant soft tissue and the height of bone graft were collected, and were all compared with the marginal bone loss (MBL). Results Of all the 20 patients, keratinized gingival loss was observed in 12 cases bilaterally, 5 cases unilaterally, and preserved in 3 cases. Three months, 6 months and 12 months after the reconstruction, the thickness of soft tissue were (5.88±0.54)mm,(3.46±0.30)mm,(3.17±0.31)mm,separately;and the height of bone graft were(2.36±0.23)mm,(2.17±0.19)mm, (2.05±0.22)mm,separately.Three months,6 months and 12 months after the implantation,the mesial MBL were(1.09±0.32)mm, (1.22±0.37) mm, (1.36±0.46) mm, separately;and the distal MBL were (1.10±0.29) mm, (1.25±0.31) mm, (1.35±0.39) mm, separately.Statistical analysis revealed that the keratinized gingiva and thickness of soft tissue were both positively correlated with the MBL,and the height of bone graft was inversely correlated with the MBL.Conclusion For the oral implant patients after mandibular reconstruction,the height of the bone graft should be increased and the thickness of soft tissue should be reduced.And keratinized gingiva should be preserved as much as possible if oncological safety is allowed during mandibular resection.

Key words: Implant retention rate, Keratinized gingiva, Fibula reconstruction, Mandible defect