Kaplun D. Improvement of the procedure of lifting and mobilization of periodontal flaps when performing dental surgeries

Based on the designated tasks, we have created a mathematical model of the deformation of mucosal flaps during flap surgeries in the oral cavity during the first stage of the alveolar process augmentation. Given the fact that one of the factors which affect the vertical and horizontal atrophy of the alveolar process is a violation of microcirculation of the mucous flap, we have performed an attempt of biomechanical substantiation of the plastic stretching and physiological limits of narrowing of the vessels with the purpose of preserving their function of transporting blood at the postoperative stage. Along with that, we have applied Hooke's law to study linear relationships between stress and strain components. The mathematical model was constructed in the form of a parallelepiped with faces that are parallel to the coordinate axes and are prone to the action of normal stress, but in contrast to skin and fat flaps, this stress is evenly distributed over two opposite faces with gradual stretching. Unlike other authors, we studied the relationship between strain and stress using two physical constants: the modulus of elasticity under tension and the Poisson's ratio, which, in 8 contrast to the digital constants of the skin, is 0.012-0.016. In our opinion, this fact affects the impossibility of stretching the mucosal flap within greater ranges than 4-6% of its initial length, which was later confirmed by morphological studies.