Influence of Implant Type on Clinical and Radiologic Outcomes: A Cross-Sectional Private Practice-Based Analysis.

Objectives To compare tissue-level (TL) and bone-level X (BLX) implants regarding peri-implant bone level alterations, survival, and complication rates over a 3-years.Materials And Methods In this retrospective, non-interventional clinical study, patients that had received either TL or BLX implants (both: Straumann AG), with at least one clinical follow-up (minimum 6 months), were included. Bone-level alterations and bone peaks were evaluated at baseline (implant placement) and at follow-ups from dental radiographs. In addition, clinical follow-ups included the recording of the presence of keratinized mucosa and the registration of technical complications (e.g., chipping fractures). For statistics, descriptive analyses, t-tests, and a random-effects linear regression analysis were applied.Results A total of 146 implants (73 TL and 73 BLX) were included. TL implants showed a survival rate of 100%, whereas BLX implants showed a survival rate of 98% after 3 years. TL implants showed significant mesial bone gain (0.08 mm, p = 0.018) between 2- and 3-year follow-ups, with a notable difference (0.21 mm, p = 0.041) compared to BLX implants. At distal bone levels, TL implants showed initial bone loss (0.12 mm, p = 0.020) at 6 months but gained bone (0.07 mm, p < 0.001) between 2 and 3 years, whereas BLX implants showed significant distal bone loss (0.15 mm, p = 0.038) over 3 years. The number of complications was higher in BLX implants. BLX implants with a band of keratinized mucosa > 2 mm showed smaller bone level alterations.Conclusions Both TL and BLX implants performed similarly in terms of clinical and radiological outcomes. However, at the mesial aspect, bone level alterations in TL implants were smaller than in BLX implants, and complications were less frequent. Keratinized mucosa seems especially beneficial in BLX implants. As implant selection was based on clinical indication, the two groups differed in baseline characteristics, and this should be considered when interpreting the between-group comparisons.