Clinical efficacy of occlusive splints manufactured by computer modeling and volumetric printing in patients with bruxism: research results and a clinical case
Authors: Apresyan Samvel V. , Stepanov Alexander G. , Gadzhiev Magammed A. , Borodina Irina D. , Heigetyan Artur V. 
Published: September 2022

BACKGROUND: Among dental diseases, various types of musculoskeletal dysfunctions occupy a special place. The myogenic theory of temporomandibular joint dysfunction is interesting, where the fundamental role is assigned to the parafunctional state of the masticatory muscles. Analysis of the results of electromyographic studies has shown that patients with TMJ disorders complicated by muscle hypertension have significant functional disorders of the masticatory muscles. Also, the causes of TMJ dysfunction include bruxism, which can occur against the background of parafunctions of the masticatory muscles. To date, there are a large number of methods for the treatment of TMJ dysfunction: splint therapy, occlusive and immobilizing splints. CAD/CAM computer technologies have also become widespread, which are used for the manufacture of these structures. But there are no uniform treatment standards, therefore, studies and comparisons of different techniques are relevant.
AIM: the effectiveness of treatment of patients with bruxism by developing a clinical protocol for the use of an occlusive splint made by volumetric printing.
MATERIAL AND METHODS: To evaluate the effectiveness of occlusive splints manufactured by computer milling and 3D printing in patients with bruxism. All study participants at the stage of formation of clinical groups underwent a comprehensive dental examination, which included a clinical and instrumental examination, surface electromyography of the masticatory muscles, computer monitoring of occlusion, cone-beam computed tomography of the TMJ. To exclude the somatoform component from the pathogenesis of bruxism, an electroencephalogram (EEG) was performed in all patients at the stage of formation of clinical groups. At the first stage of treatment, all patients underwent selective grinding of centric and eccentric interferences under the control of a T-scan computer occlusion monitoring device, after which the therapeutic position of the mandible was determined, stabilizing nocturnal occlusal splints made by volumetric printing were manufactured and fixed. Monitoring of treatment results included clinical and instrumental examination and surface electromyography of the masticatory muscles, carried out 3.6 and 12 months after the start of treatment. Upon completion of treatment, an assessment of the integrity of occlusal splints was carried out.
RESULTS: According to the results of the performed myography, at the time of the start of treatment, the PU coefficient was 74%, after 3 months, it significantly decreased by 6%, after 6 months, its decrease was recorded by 11%, and after 12 months by 16%. The assessment of the integrity of the occlusal splint was carried out at the end of treatment after 12 months, by combining virtual tire models in a computer program before and after the start of treatment obtained by laboratory scanning. When analyzing the comparison of virtual tire models, their almost complete identity was revealed, with the exception of one area on the occlusal surface, which is 0.044 mm, which is not critical in the general treatment concept.
CONCLUSION: Taking into account the positive result of clinical testing of the proposed technology, it is advisable to conduct a randomized study to evaluate the effectiveness of the use of occlusive splints made by computer modeling and volumetric printing from domestic material in the treatment of patients with musculoskeletal dysfunction complicated by bruxism.