Chernykh N. Clinical and laboratory substantiation of attachments design in removable partial dentures with different rigidity.

The dissertation is dedicated to clinical, laboratory and mathematical substantiation of partial dentures with attachments fixation design, taking into account the structural peculiarities of the alveolar bone and toothless part of the jaw, and the abutment teeth periodontal tissues condition. For the purpose of diagnosing overloading zones in abutment teeth we applied mechanics and mathematical analysis of stress-strain state. It was found that the partial denture with labile attachment has larger load amplitude on abutment teeth and alveolar process than the prosthesis with a rigid attachment. Evaluation of the results of EMG study of masticatory muscles and chewing efficiency showed that in 12 months after using RPDs with labile attachments in all types of patients with alveolar bone II and III by Elbrecht registered alignment ratio of periods of activity and rest inside the chewing cycle, showed an increase in the k-values of 20-25 %. Our analysis of the results of clinical and laboratory research recommends using RPDs with attachments of various degrees of rigidity in patients with distal dentition defect, in I and IV types of alveolar bone by Elbrecht - labile attachments, and in II and III types - rigid. In the dissertation the theoretical generalization and practical substantiation of treatment using RPDs with varying degrees of attachments hardness is provided with the aim of regulation the power of loading periodontal tissues of abutment teeth with attachments and prevention the negative impact of fixing elements, which reduces the period of adaptation and improves the quality of prosthetics.