Table 5.
Clinical parameters found.
| Author/Year | Patients (n) | Connection (n) | BoP | PD (mm) | Plaque | Follow-Up (Months) | Conclusions |
|---|---|---|---|---|---|---|---|
| Pozzi et al., 2014 [26] | 34 | ICC (44) | Not detected around any implants | NR | Low presence | 16 | The MBL was statistically significantly lower in the back-tapered neck configuration with CC and built-in platform shifting compared with the straight neck configuration with the flat-to-flat implant–abutment interface and external hexagonal connection. |
| EH (44) | Not detected around any implants | Low presence | |||||
| Doornewaard et al., 2021 [27] | 27 | I-MT (24) | Positive in 33 implants | Mean of 4.5 | No significant impact between implant type and position | 36 | The implant–abutment connection (internal vs. external), implant neck design (microthreaded vs. non-microthreaded), and implant position (anterior vs. posterior) have no influence on peri-implant bone remodeling after implant placement, no impact on peri-implant bone level after initial remodeling, and no effect on peri-implant health parameters. |
| I-NMT (25) | |||||||
| E-MT (25) | |||||||
| E-NMT (24) | |||||||
| Platform matching | Positive in 8 sites | Mean of 2.1 | 36 implants with plaque | ||||
| Pessoa et al., 2017 [28] | 12 | External hexagon (24) | No bleeding | 1.57 ± 0.9 | NR | 12 | Within the limitations of this study, it can be concluded that varying implant–abutment connection types will result in diverse early peri-implant bone remodeling. The present findings suggest that MT connections are more efficient in preventing early peri-implant bone loss compared to EH connections. |
| Morse Taper (24) | No bleeding | 1.36 ± 0.7 | |||||
| Glibert et al., 2018 [29] | 21 | I-MT (20) | 23.4% was recorded | Mean of 3.26 | 39.5% of implants presented the plaque | 12–21 | From this RCT, it is concluded that crestal bone remodeling is not affected by the implant–abutment connection or microthreads. Bone remodeling is a multifactorial process and might be more dependent on other factors than implant design itself. |
| I-NMT (21) | |||||||
| E-MT (20) | |||||||
| E-NMT (19) | |||||||
| Cooper et al., 2016 [30] | 36 | ICI (44) | Less than 2% | NR | Low presence | 36 | Comparing two implant designs revealed minor differences in marginal bone responses from permanent restoration to 3 years. Significantly more apical MBLs were recorded for EXI implants. Furthermore, more positive papilla scores were found between adjacent ICI implants than between adjacent EXI implants. EXI implant displayed more abutment complications than the ICI implant. |
| EXI (42) | Less than 2% | Low presence | |||||
| Penarrocha-Diago et al., 2013 [31] | 15 | EH (69) | NR | NR | NR | 12 | Bone loss after 6 and 12 months proved statistically significant between the two groups, with comparatively greater loss in the case of the Osseous® implants vs. the Inhex® implants. Regardless of the heterogeneity of the two groups (neck shape, microthreads, surface texture), the implant–abutment connection appears to be a significant factor in peri-implant crestal bone levels. |
| IC (72) |
vs.: versus; NR: non-reported; RCT: randomized and controlled trial; ICI: internal conus design implants; ICC: internal conical connection with back-tapered collar and platform shifting; EXI: external hexagon design implants; EH: external hexagon with the flat-to-flat interface; MT: microthreads; I-MT: internal with microthreads; I-NMT: internal without microthreads; E-MT: external with microthreads; E-NMT: external without microthreads.