Marginal Bone Loss and Clinical Complications in Surviving Implants and Recently Placed Implants Splinted Together: A Retrospective Study

Purpose: The objective of this study was to compare marginal bone loss (MBL) and clinical complications between surviving implants (SIs) and recently placed implants (RIs) splinted together to support a fixed partial restoration (FPR).
Materials and Methods: This retrospective study employed the medical records of patients treated with implant-supported FPRs in the Maccabi-Dent Dental Clinic. Patients were included if they were over the age of 18 years, were treated with RIs adjacent to existing SIs that had previously supported FPRs for more than 1 year, and the RIs and SIs were splinted to support new FPRs. Patients who did not receive annual follow-up or whose records had nondiagnostic radiographs or lacked sufficient restorative data were excluded. MBL was assessed at the last available radiograph and compared to one taken 1 year after loading the splinted RIs and SIs together. Clinical complication data were gathered from patient records.
Results: The medical records of 1,907 patients treated with a total of 7,306 implants were examined. Data from 187 implants were extracted from 46 patient records that met the inclusion criteria, with 96 RIs and 91 SIs supporting 56 FPRs. Mean followup was 39 ± 17.5 months. During the follow-up, two implants failed. The overall survival rate was 98.94% (98.96% in RIs and 98.91% in SIs), and the mean MBL in all implants was 0.41 ± 0.58 mm (0.4 ± 0.53 mm in RIs and 0.42 ± 0.45 mm in SIs). Peri-implantitis was reported in eight (4.3%) implants (four RIs and four SIs), screw loosening was reported in nine (4.8%) implants (three RIs and six SIs), ceramic chipping was reported in three (5.3%) restorations supported by four RIs and six SIs, and decementation was reported in one (1.8%) restoration supported by one RI and one SI. There was no statistically significant difference in survival rate, MBL, peri-implantitis, or screw loosening between RIs and SIs.
Conclusion: There was no statistically significant difference in MBL or clinical complications between RIs and SIs. Splinting RIs and SIs for new prosthetic restoration support is a reasonable treatment choice with a high implant survival rate, low incidence of complications, and acceptable MBL.