###### Abstract  
The purpose of this study was to present the level of bone tissue deformation after drilling under variable conditions in three different dental implant systems in a microscopic analysis. Straumann, Oststem, and S-Wide systems were used to drill boreholes in 27 porcine ribs at three different rotation speeds and under three different cooling conditions. The material was analyzed using a Nikon 80i microscope. The analysis concerned the morphological quality of the obtained boreholes. The statistical analysis revealed that satisfactory results in all drilling systems were obtained when the rotational speed did not exceed 800 revolutions per minute (rpm) regardless of the cooling temperature. However, increased rotational speed and cooling at 4 \({}^{\circ}\)C produced better results than without cooling in all the tested systems. Different implant systems have unique drill geometry and therefore generate differences in tissue damage under various conditions. In the experiment, a sufficient required structure was obtained in all systems, but the Straumann system yielded the best results under all the examined conditions. implant drilling; bone tissue; osseointegration +
Footnote †: journal: Applied Sciences  
initial stability. It is important to underline that underpreparation of an implant osteotomy site is defined as preparation of the implant's bed narrower than the implants inserted diameter [10; 11], and over-preparation causes a wider implant bed preparation than the implant's inserted diameter [8]. According to [PERSON] et al. [12], microfractures during implant insertion can happen but depend on the discrepancy between the diameter of the implant and the implant's bed, as well as bone density. [PERSON] et al. [13] confirmed that implants placed at the time of extraction and inserted into native bone, not directly into the extraction socket, have a higher degree of initial stability. According to the literature, this stability has been demonstrated as a necessary condition required to obtain the proper osseointegration of the dental implant [14; 15]. It should be noted that it has long been observed that too rigid anastomoses could lead to osteolysis. Good-quality drills and correctly selected speed should allow us to obtaining a smooth, even surface of the borehole, without leaving collagen fiber debris or ground material saturated with hydroxyapatite. The generation of excessive temperature changes is influenced by many factors, including drill speed, the geometry of the drill surface, drill wear, and method and intensity of cooling [16; 17; 18]. This is particularly important while drilling long tunnels in bone, such as preparation for bicortical or zygomatic implants [19; 20]. The shape/material of the drill is important for the subsequent healing process and implant integration. Leaving dead, carbonated or calcified tissues can affect the induction of osteogenesis or immune response. This leads to the intensification of bone resorption, which directly translates into the ability of the implant to connect to the bone [21; 22]. Different drill geometries have an impact on the nature of the borehole, including the amount of debris remaining in the drilled hole and the degree of soft tissue damage. One of the methods of implant material classification is based on the type of material used and the biologic response it causes when implanted [23]. Among the biotolerant materials, we can distinguish metals such as Gold Co-Cr alloys, Niobium, Tantalum or Stainless steel or polymers, including Polyethylene Polyamide or Polyurethane [24]. Biointer materials examples are Titanium alloys or oxides, such as Aluminium and Zirconium oxide. Bioactive ceramic materials include Hydroxyapatites, Bioglass Carbon-silicon or Tricalculum phosphate. Microtopography of implants plays a crucial role in effective osseointegration. It is linked to microroughness at a micrometer scale and can be modified using techniques such as acid-etching, grit-blasting or coating procedures [25].