Clinical and patient-reported outcomes of implants placed in autogenous bone grafts and implants placed in native bone: A case-control study with a follow-up of 5-16 years

Aims To compare the radiographic marginal bone levels of implants placed in sites previously augmented with autogenous bone grafts and implants placed in native bone. Secondary outcomes included: implant survival, periodontal/peri-implant parameters as well as short- and long-term patient-reported outcome measures. Materials and methods The study was designed as a case-control study including 38 patients equally distributed into two groups (previously augmented with autogenous bone blocks [AB] and implants placed in native bone [NB]). In total, 67 implants were placed. Clinical, radiographic and patient-reported outcome measures (PROMs), and complication rates were assessed based on a chart review and at a follow-up examination (>= 5 years after implant placement). Nonparametric mixed models were applied for the comparison of the two groups because of the clustered data. The data were analyzed descriptively, and p-values were calculated using nonparametric mixed models to account for the clustered data. Results The mean follow-up time was 10.2 years (range 6-13 years; AB) and 8.3 years (range 5-16 years; NB). One implant was lost in group NB (97.5% survival rate) and none in group AB (100%). Following primary augmentation, six major complications (wound dehiscences, acute pulpitis, intra- and extraoral sensitivity disturbances) were observed at the donor sites. At time of implant placement, only minimal complications occurred and only in group NB. Median marginal bone levels at the follow-up were significantly higher in group NB (1.15; Q1: 0.50 mm/Q3: 1.83 mm) than in group AB (1.58; Q1: 1.01 mm/Q3: 2.40 mm; p = 0.0411). Probing depth, bleeding on probing and recession values were similar in both groups. PROMs revealed high visual analog scale values (i.e., high satisfaction) for both procedures. Conclusions Dental implants placed in sites augmented with autogenous bone or in native bone revealed healthy peri-implant tissues after 5-16 years. Marginal bone levels were significantly higher for implant placed in native bone. Complications following primary augmentation encompassed every third patient but were mostly transient.