Purpose: To compare the aspect of the reproduction accuracy in studied methods of determination of the (CR) of jaws using the digital research methods. The methods used were bilateral manipulation by P.E. Dawson, frontal deprogrammer, leaf gauge, and intraoral device for recording of Gothic arch angle. Methods: To determine the reproduction accuracy of the centric relation of jaws, we examined 5 patients with intact dentition in a prosthetic dentistry clinic (first class in Angle’s system). For each method, 20 registrations of the centric jaw relation were carried out by one operator. The breaks between definitions were 30 minutes. A total of 400 CR recording operations were carried out (400 records of CR). In order to study the reproducibility of CR determination methods, 200 recorded mandible positions were analyzed by means of an analog-to-digital method (a macro kit Canon 650D, Canon 60 mm macro IS USM f2.8, Canon macro ring MR-14 EX and the computer program Adobe Photoshop) to assess the first occlusal contact obtained in the CR of jaws, while the other 200 were analyzed by means of a digital method (the computer program Avantis for 3D modeling, Prime as a laboratory 3D scanner (DOF), and Trios as an intraoral scanner (3Shape)) to assess the spatial position of the mandible in the CR. Statistical analysis was carried out using STATISTICA-10. In all statistical analysis procedures, the critical significance level p was assumed to be 0.05. Results: In the study of the data by means of the computer program Avanti 3D, the reproducibility of the mandible position in the CR reached 0.119 ± 0.012 mm for frontal deprogrammer, 0.225 ± 0.028, p ≤ 0.05 for bilateral manipulation by Dawson P.E., 0.207 ± 0.02, p ≤ 0.05 for leaf gauge, and 0.120 ± 0,013, p ≤ 0.05 using an intraoral device for recording the Gothic arch angle. The analog-to-digital method showed an identical tendency for reproduction of the mandible position. Conclusions: The digital analysis we made using the Avantis 3D program showed, with high confidence, that the maximum reproducibility of the CR position was reached by using our own design frontal deprogrammer and the device for recording Gothic arch angle.
This article substantiates a comprehensive approach to diagnosis and treatment during revision orthopedic prosthetics in the absence of obvious musculoskeletal dysfunction. A 48-year-old woman with no musculoskeletal complaints is presented. A comprehensive diagnosis revealed significant changes: chin displacement, jaw angle asymmetry, muscle tension, narrowing of the TMJ joint space, divergence of jaw movement trajectories, and uneven tooth wear. A multi-stage treatment plan was developed using temporary restorations to correct jaw position, allowing the patient to adapt to the new position. A follow-up examination after 6 months revealed significant improvement: restoration of joint symmetry, normalization of jaw movement, elimination of facial asymmetry, and improved aesthetics. The patient had no complaints. Conclusion. Comprehensive approach is justified in revision prosthetics, even without obvious symptoms, to restore all components of the TMJ, improve adaptation to prostheses and ensure long-term stability.