Resinas Bulk-fill : comportamento clínico e impacto psicossocial na autopercepção estética dos pacientes

Abstract

Bulk-fill resin composites were launched on the market in order to reduce the operating time without impacting the mechanical properties of the materials. These materials, in general, may present greater translucency, being more suitable for posterior teeth, presenting acceptable aesthetics and being a favorable clinical option in cases of amalgam restorations replacement. Therefore, the present thesis consists of three chapters that aimed to evaluate the clinical behavior of restorations performed with three bulk-fill resins and a conventional one after the amalgam restorations replacement. The psychosocial impact on the patients' self-perception after this restorative procedure was also evaluated. For this, 47 patients were selected with at least four Class I and/or II amalgam restorations when replacement was indicated. Randomly, restorations were performed using the incremental [Z350XT (ZXT)] and bulk-fill filling technique [Filtek BulkFill (FBF), SonicFill (SF) and Opus BulkFill (OBF)]. Chapter 1 evaluated the postoperative sensitivity (POS), using a numerical rating scale and a visual analog scale after 24 h, 7 and 30 days. Chapter 2 is a prospective cohort study that investigated the psychosocial impact of amalgam restorations replacement with resin composites. Thirty patients were evaluated using the Brazilian version of the Psychosocial Impact of Dental Aesthetics Questionnaire (PIDAQ) immediately before (T1) and six months after (T2) the restoration replacement. Chapter 3 evaluated the clinical performance of restorations, after polishing and in the periods of 6 and 24 months, according to the criteria of the World Dental Federation (FDI). The data were submitted to statistical analysis (α = 0.05). The results of Chapter 1 showed that the restorative technique and the bulk-fill systems used did not affect POS. The volume of the cavities significantly influenced the POS after 24h (p = 0.038). When the depth of the cavity was analyzed alone, there was no statistical difference (24h p = 0.23; 7 days p = 0.60; 30 days p = 0.70). The cause of replacement, the type of cavity and the number of surfaces restored did not affect the patient's POS response. In chapter 2, significant differences between T1 and T2 were found in the self-confidence (p <0.001) and aesthetic (p=0.018) domains of PIDAQ, but the social impact (p = 0.357) and psychological impact (p=0.108) domains were not significantly affected by restorative procedures. Sex, age, education, family income and consumption of tobacco and alcohol did not affect significantly the patients' aesthetic self-perception. Chapter 3 showed that, after two years, the retention rate of restorations independent of the group was 100%. After 24 months, the ZXT group showed small discrepancies in marginal adaptation compared to baseline (p=0.04). Among the groups, ZXT and FBF showed worse marginal adaptation than SF and OBF (p = 0.003). After 6 and 24 months, the ZXT (6M - p = 0.026; 24M p <0.001) and SF (6M - p = 0.026; 24M - p = 0.027) groups showed statistically significant marginal discoloration. After 24 months, FBF (p=0.016) showed statistically significant marginal pigmentation, while the OBF group showed no significant difference in any period (6M p=0.241; 24M - p=0.101). In conclusion, the restorative technique and the bulk-fill systems did not influence the POS in the evaluated period. In addition, the aesthetics of posterior restorations proved to be significantly relevant to the patients' aesthetic self-perception. In the clinical evaluation, all bulk-fill systems were clinically adequate after 24 months, but the performance depends on the material.