CLINICAL EVALUATION OF LONG-TERM RESULTS OF PARTIAL CROWN RESTORATIONS WITH DIFFERENT MATERIALS IN PATIENTS WITH GENERALIZED PERIODONTITIS

Abstract

Purpose of the study. To evaluate the direct composite and indirect zirconia partial crown restorations, and the periodontal status of abutment teeth in patients with generalized periodontitis compared to healthy persons at long-term follow-up. Research methods. 60 patients aged 21-45 years, equally men and women, who needed to replace partial crown caries decays, Black class II, located above or at the level of the gingival margin, were examined and treated. Group I (comparison) included 30 patients with clinically healthy periodontal tissues, group II – 30 patients with generalized periodontitis, I-II degrees, chronic course. In both groups, according to indications, partial crown defects of the contralateral teeth were restored with paired restorations: on the one hand – direct composite, on the other – indirect zirconium, manufactured using CAD/CAM technology. In 1 year, the restorations were evaluated according to the modified criteria of the United States Public Health Service (USPHS) and by means of index periodontal assessment for the abutment teeth. Scientific novelty. According to the USPHS criteria, 90.0% of composite restorations and 100% of zirconium restorations were successful in the group I. In the group II, 80.0% of composite restorations and 100% of zirconium restorations were successful.Complications for composite restorations arose due to disorders of the anatomical shape (10.0%) and marginal fit (20.0%). At the same time, among the causes of negative consequences of restorative treatment in people with healthy periodontium, wear of occlusal surfaces prevailed, and in patients with generalized periodontitis, marginal fit was impaired. Significant differences in dental plaque indices for the study groups I and II indicate that indirect zirconium restorations contribute to maintaining the hygiene of periodontal tissues of abutment teeth, unlike direct composite restorations. The presence of dental plaque provokes inflammatory phenomena in the gums, as indicated by the increase in the gingival index and the gingival sulcus bleeding index when using composite materials for patients in both study groups (P < 0.05).As a result, 1 year after restorative dental treatment, in individuals with healthy periodontium, they observed localized loss of gingival attachment and formation of periodontal pockets. In patients with generalized periodontitis, composite restorations, unlike zirconia restorations, cause a worsening of the course of the disease, as evidenced by the increase in all periodontal indices and the bone density index (BMD) from baseline values (P < 0.05). Conclusions. The condition of periodontal tissues affects the effectiveness of partial crown restorations, and in patients with generalized periodontitis, the success of restorative treatment is lower than in healthy persons. The results of the study confirmed the greater clinical effectiveness of indirect zirconium restorations compared to direct composite restorations according the quality criteria and periodontal status indicators in both healthy and patients with generalizedperiodontitis. In generalized periodontitis, giving preference to zirconium partial crown restorations allows preventing complications of the clinical course of the disease.