Effect of different placement techniques on color stability and surface roughness of resin composites / Efeito das técnicas de inserção e alisamento na estabilidade de cor e rugosidade superficial de resinas compostas

Abstract Introduction Longevity and clinical success of dental restorations can be influenced by many factors during the restorative procedures. Objective This study aimed to evaluate the influence of different placement techniques on color stability and surface roughness of two resin composites. Material and method The groups of specimens (n=10) were divided according to resin composite (FiltekTM Z250 XT and FiltekTM Z350 XT) and placement technique: Mylar strip, spatula, dry brush, modeling liquid, and surface sealant. Color stability and surface roughness were accessed using a spectrophotometer (CIELab color space) and a rugosimeter (standard cutoff of 0.8 mm), respectively, after water storage. Subsequently, the specimens were immersed in coffee for 48 h and final color was measured. The data were analyzed using ANOVA and the Tukey's post hoc test (α=5%) and the correlation between surface roughness (Ra) and color change (∆Eab) was assessed using the Pearson's correlation coefficient. Result The different placement techniques influenced Ra and ∆Eab on both resin composites. The groups treated with surface sealant showed greater difference in ∆Eab for both resin composites. The FiltekTM Z250 XT resin showed greater color stability compared with the FiltekTM Z350 XT resin regardless of the placement technique used. Ra of each placement technique was similar among the resin composites except for the FiltekTM Z350 XT modeling liquid group, which presented lower Ra values compared with those of FiltekTM Z250 XT. A correlation between Ra and staining was identified (p=0.268). Conclusion Color stability and Ra are influenced by different placement techniques.

Resumo Introdução A longevidade e o sucesso clínico das restaurações dentárias podem ser influenciados por muitos fatores durante os procedimentos restauradores. Objetivo Avaliar a influência da técnica de alisamento na estabilidade de cor e rugosidade superficial de duas resinas compostas. Material e método Os grupos de amostras (n=10) foram divididos conforme a resina composta (FiltekTM Z250 XT e FiltekTM Z350 XT) e as técnicas empregadas: tira de poliéster, espátula, pincel seco, selante de superfície. A cor e a rugosidade da superfície foram avaliadas por espectrofotômetro (espaço de cor CIELab) e rugosímetro (corte padrão de 0,8 mm), respectivamente, após o armazenamento em água. Posteriormente, as amostras foram imersas em café por 48h e a cor final foi aferida. Os dados foram analisados usando teste ANOVA e Tukey post hoc (α = 5%) e a correlação entre rugosidade da superfície (Ra) e variação de cor (∆Eab) através do coeficiente de correlação de Pearson. Resultado As técnicas de alisamento influenciaram a Ra e a ∆Eab em ambas as resinas compostas. Os grupos tratados com selante de superfície apresentaram maior diferença na ∆Eab. A resina FiltekTM Z250 XT apresentou maior estabilidade de cor comparada à FiltekTM Z350 XT, independentemente da técnica utilizada. A Ra das técnicas de alisamento foi semelhante entre os compósitos, exceto para o grupo do líquido modelador da FiltekTM Z350 XT, que apresentou os menores valores. Uma correlação entre Ra e manchamento (p = 0,268) foi identificada. Conclusão A estabilidade da cor e a Ra são influenciadas pelas técnicas de alisamento utilizadas.

Does Endodontic Re-Treatment in Primary Teeth Increase the Functional Tooth Retention? A Clinical, Retrospective, University-Based Study

Objective: To investigate the longevity of endodontic treatments and the survival of endodontic re-treatments performed in primary teeth. Material and Methods: The sample included endodontic treatments and re-treatments conducted in anterior and posterior primary teeth without sedation or general anesthesia among children attending a university dental service. Information collected retrospectively from clinical records was used for analyzing data. The Kaplan-Meier estimator test was used to analyze the longevity and survival of endodontic treatment and re-treatments, respectively. Results: A total of 73 patients with endodontic therapy in primary teeth were included in the study, and 116 teeth were analyzed. After one year, the longevity of endodontic treatments performed on primary teeth was 65.74% with an annual failure rate (AFR) of 34.2%. From 47 endodontic treatment failures, 14 teeth (29.8%) were endodontically re-treated. When the endodontic re-treatment was considered as survival, the longevity of treatments reached 68.06% with 31.9% of AFR after one year of follow-up. There was a significant increase in functional tooth retention in those patients that received an endodontic re-treatment (p<0.001). Retreatment provided an additional mean survival time of 8.3 months. Conclusion: Endodontic treatments performed in primary teeth presented a limited longevity. Endodontic re-treatment is a more conservative alternative for endodontically treated primary teeth that have failed and significantly increase tooth retention.