VERTICAL TITANIUM SCREWS WITH MODIFIED COATING TO INCREASE THE RELIABILITY OF FIXATION AND STABILIZATION OF ABUTMENTS TO THE DENTAL IMPLANT PLATFORM

Abstract

Vertical screws of abutments after dental implantation tend to loosen, unscrew and break, which is associated with low strength, tribological and corrosion properties of screw material under stress and aggressive environment in the oral cavity. The main causes of problems with dental screws are a decrease in their fatigue strength due to defects, residual tensile stresses and hydrogen pickup of surface layer, as well as the process of fretting corrosion that occurs under conditions of micro-displacement under cyclic loads of conditionally stationary tribocoupling. The design and operational characteristics of abutment screws, the main problematic properties of titanium materials are considered, the calculated dependences of torque, pre-tightening force, friction coefficients in thread and on support surface are given. The analysis of numerical values of these parameters is given. It is concluded that the use of vertical titanium screws with functional coatings is one of the ways of improving the reliability of the dental implantation system. The results of studies of the BioPateks diamond-like coating of the a-C:H/a-SiC-Ag system for vertical titanium abutment screws applied using cold atmospheric plasma are presented. The effectiveness of this coating has been demonstrated in metallographic analysis, static tensile tests, tribological studies, tests under microabrasive wear conditions, studies of barrier properties from the release of toxic vanadium and aluminum ions, studies of surface defects during fretting fatigue. The BioPateks coating and its application technology can be used both in industrial and in clinical and laboratory conditions. For these purposes, small-sized and low-energy equipment is used.