For a few years, there has been a trend towards minimally invasive implant treatment concepts avoiding bone augmentation even in very atrophic edentulous jaws. These concepts aim to make an implant treatment with a shorter duration, with less inconvenience such as swelling or pain and possibly also economically more attractive [1]. If the implant treatment is less invasive, because of the possible smaller surgical risks and lower costs, implant therapy can be provided for a larger number of patients. Minimally invasive mainly means the adaptation of the implant dimension or position to the existing anatomy to avoid bone augmentation procedures [1]. One possible strategy to avoid augmentations in the distal atrophic maxilla is to insert short implants. In recent reviews, implants of less than 10 mm are not inferior to longer implants relating to bone loss or survival rate [2,3,4]. But also for the insertion of short implants, the bone height in the atrophic posterior maxilla is often not enough [5].

An alternative to short implants are longer tilted implants [6] with a possibly higher primary stability combined with the posterior position of the implant shoulder [7,8,9]. These characteristics seem to make them especially suitable for immediate loading in the edentulous jaws [10] as it is often performed [5]. This treatment concept with loading on the same day appears to achieve high patient satisfaction [1], but there are also some disadvantages. Tilted implants might be more difficult to insert and need technical angulated abutments. To position the implants in an optimal position parallel to the anterior sinus wall, a computer-guided implant planning and navigated insertion is more often needed.

Different implant systems have been investigated using the concept of tilted implants [11], but due to the different geometric properties and prosthetic components, they may behave differently, so that all systems used for this concept must prove their suitability. Because this implant type was previously rarely investigated in the concept of immediate loading [12], the aim of this retrospective study is to evaluate the success rate of Bredent blueSky™ implants (Bredent GmbH, Senden, Germany) in immediate full-arch loading with tilted posterior implants using minimal invasive surgery. In addition to the osseointegration and bone loss, the stability parameters’ implant stability quotient (ISQ; measured by resonance frequency analysis (RFA)) and Periotest (PT) values were compared between tilted and axial implants and their changes after osseointegration were recorded. The suitability of the chosen combination of implants, abutments, and materials for the provisional restorations after use in a clinical setting should be examined.