Abstract: PURPOSE: To investigate 1 year follow-up results of short mini dental implant (MDI) and conventional-size MDI for mandibular overdentures, and to provide reference for clinical application. METHODS: Thirty edentulous patients undergoing short MDI and 30 edentulous patients undergoing standard MDI were enrolled. The baseline data, clinical peri-implant indicators, implant survival and success rate, implant complications and patient satisfaction were compared between the two groups. SPSS 20.0 software package was used for statistical analysis. RESULTS: The marginal bone loss (MBL) and probing depth(PD) of short MDI group 1 year after implantation were less than those in standard MDI group, but with no significant difference(P>0.05). The modified plaque index (MPI) and modified bleeding index (MBI) 1 year after implantation in short MDI group were significantly less than those in standard MDI group(P<0.05). The 1-year implant survival rate and success rate of short MDI group were higher than those of standard MDI group, but with no significant difference(P>0.05). The total incidence of complications in standard MDI group was significantly higher than that in short MDI group(P<0.05). The satisfaction rate of short MDI group was significantly higher than that of standard MDI group in terms of implant stability, chewing function, speech, comfort and aesthetics(P<0.05). CONCLUSIONS: Application of short MDI for mandibular overdentures in edentulous patients with severely atrophied alveolar ridges has higher clinical effect and satisfaction rate.

Key words: Mandibular overdenture, Severely atrophied alveolar ridges, Edentulous case, Mini dental implant, Prospective cohort study