Effect of antioxidants on adhesive bond strength to bleached enamel.

OBJECTIVE: To evaluate the influence of antioxidants (ATX) resveratrol, winter's bark, green tea and yerba mate on the bond strength between bleached enamel and the nanohybrid composite resin. METHODOLOGY: Bovine incisor crowns (n = 132) were randomly divided into 22 groups (n = 6) according to the application times (5, 10, 15, 30, and 60 min) of each antioxidant. Teeth restored without previous bleaching or ATX constituted the non-bleached control group (NB Ctrl) (n = 6), and teeth restored after bleaching and without ATX represented the bleached control group (B Ctrl) (n = 6). The 35 % hydrogen peroxide was applied for 45 min (3 application of 15 min) to the buccal enamel surface. ATX was used after bleaching for the specified time of each group and removed with air-water spray. The enamel was etched with 37 % phosphoric acid (30 s) and rinsed with air-water spray. The adhesive resin was applied to the enamel dry surface. Teeth were restored using 1 mm composite resin increments (10 × 10 × 3 mm) and sectioned in test specimens of 6 mm in length and 1 mm2 in cross-sectional area submitted to microtensile bond strength test (0.5 mm/min). The load (N) at failure was recorded, and the bond strength (σt) was calculated (MPa). The fracture area was analyzed under optical microscopy, and failures were classified as cohesive, mixed, or adhesive. Data was evaluated by Kruskal-Wallis and Dunn tests (p ≤ 0.05). RESULTS: B Ctrl group presented lower σt than NB Ctrl (p < 0.001). Applying resveratrol for 5 or 10 min, winter's bark for 10 or 15 min, green tea for less than 15 min, and yerba mate for 15 min provided similar σt between bleached enamel and nanohybrid composite to the control group. CONCLUSION: Restorative procedures performed immediately after tooth bleaching compromises adhesion. Experimental antioxidants applied to bleached enamel can increase the immediate bond strength of restorations performed directly after bleaching, with similar values to those observed in unbleached enamel. CLINICAL SIGNIFICANCE: This study presents promising results to support the use of antioxidants on the recently bleached enamel to allow adhesive tooth restorations. The immediate bonding obtained using antioxidants was similar to the one achieved in non-bleached enamel in brief application times. Green tea extract and resveratrol were able to restore the bond strength to bleached enamel in a short application time of 5 min. The reduction in the required application time holds the potential to decrease the overall duration of the clinical section, offering clinical advantages and improving the feasibility of using antioxidants on the bleached enamel prior to adhesive procedures.

Reflexo disfórico da ejeção do leite: conhecimento e diferenciação com transtornos mentais puerperais entre ginecologistas e obstetras paranaenses / Dysphoric milk ejection reflex: knowledge and differentiation with puerperal mental disorders between gynecologists and obstetricians from Paraná

Objetivo: Identificar o conhecimento dos médicos ginecologistas e obstetras do Paraná sobre o reflexo disfórico da ejeção do leite e seus diagnósticos diferenciais. Métodos: Estudo observacional transversal com médicos ginecologistas e obste- tras associados ao Conselho Regional de Medicina do Paraná. A coleta de dados foi realizada por questionário online compreendendo perguntas de identificação do profissional, tempo de formação, conhecimento e experiência com reflexo disfóri- co da ejeção do leite, dificuldades de diferenciação entre os transtornos mentais puerperais, além da abordagem das questões psicológicas puerperais com as pa- cientes. Os resultados foram expressos por frequências e percentuais. Valores de p menores que 0,05 foram considerados significativos. Resultados: Entre os partici- pantes, 39,1% desconhecem o reflexo disfórico da ejeção do leite. Dos profissionais que já fizeram o diagnóstico, 72,4% apresentaram dificuldade em realizá-lo. Houve acerto majoritário em relação ao momento de ocorrência dos sintomas (90,6%) e tempo de duração (90,6%), mas deficiência no reconhecimento de todos os sin- tomas (3,1%), início das manifestações clínicas (12,6%) e tratamento (44%) pelos profissionais que conhecem o reflexo disfórico da ejeção do leite. Entre os especia- listas, 21,5% sentem-se capazes para diferenciar os três distúrbios e 24,1% têm difi- culdade na diferenciação entre as patologias. Apenas 65,5% dos médicos abordam as dificuldades emocionais na amamentação e, segundo 78,1% dos profissionais, poucas pacientes perguntam ou nunca perguntam sobre essas dificuldades. Con- clusão: O reflexo disfórico da ejeção do leite é uma condição pouco conhecida e confundida com outros transtornos mentais puerperais. É necessária maior divul gação sobre o tema entre os ginecologistas e obstetras, a fim de melhorar a assistência às puérperas, refletindo na persistência da amamentação e seus benefícios.

Objective: To identify the knowledge of gynecologists and obstetricians in Paraná about the dysphoric milk ejection re- flex and its differential diagnosis. Methods: Cross-sectional observational study was conducted with gynecologists and obstetricians associated in the Regional Council of Medicine of Paraná. Data collection was dove through an online question- naire with questions about professional identification, years of experience, knowledge and experience with the dysphoric milk ejection reflex, differentiation puerperal mental disorders difficulties, as well as the approach of postpartum psycholo- gical issues with patients. Results were expressed in frequen- cies and percentages. P values less than 0.05 were considered significant. Results: 39.1% of the participants unknown the dysphoric milk ejection reflex. Among the professionals who had diagnosed dysphoric milk ejection reflex, 72.4% reported difficulties in making the diagnosis. There was a high level of correct answers regarding the timing of symptoms (90.6%) and duration (90.6%), but deficiencies were observed in recognizing all symptoms (3.1%), onset of clinical manifestations (12.6%), and treatment (44%) by professionals who were familiar with dysphoric milk ejection reflex. 21.5% of specialists felt capab- le of differentiating between the three disorders, while 24.1% had difficulty in differentiating between the pathologies. Only 65.5% of doctors approach emotional difficulties in breastfee- ding and, according to 78.1% of professionals, few patients ask or never ask about these difficulties. Conclusion: Dysphoric milk ejection reflex is a condition that is poorly known and of- ten confused with other postpartum mental disorders. Greater awareness about this topic is necessary among gynecologists and obstetricians to improve care for postpartum women, lea- ding to the continuation of breastfeeding and its benefits.