Plant extract incorporated into glass ionomer cement as a photosensitizing agent for antimicrobial photodynamic therapy on Streptococcus mutans.

BACKGROUND: A plant extract (EB) incorporated into glass ionomer cement (GIG) could be a potential photosensitizer for Antimicrobial PDT (aPDT) against caries-microorganisms, replacing methylene blue (MB), due to the presence of chlorophyll. GIC + EB + aPDT could be an therapeutic alternative to dentin decontamination and sealing, allowing reduction of operative time. OBJECTIVE: Evaluate Dioscorea altissima (EB) incorporated into GIC as a photosensitizer for aPDT against Streptococcus mutans. METHODS: Groups (n = 24; ntotal = 192): G1-GIC; G2-GIC + LASER; G3-GIC/EB; G4-GIC/EB + LASER; G5-GIC+MB; G6-GIC + aPDT; G7-GIC/EB + MB; and G8 - GIC/EB+aPDT. In aPDT groups, MB was the photosensitizer. In LASER groups, MB was not used. The irradiation protocol was 660 nm/100 mW/5 J/150 J/cm²/50 s, with a 5-min pre-irradiation time for the MB groups. Antibacterial assays were carried out in 24-well microplates. The wells were completed with one milliliter of a S. mutans in BHI at 1.3 × 108 CFU/mL suspension. After incubation, PDT or laser was performed. After MTT bacteria viability test, the data were submitted to the Kolgomorov-Smirnoff normality test, followed by one-way ANOVA and Tukey's posterior test, α < 0.05. RESULTS: Group G6 showed significant inhibition (p < 0.001), followed by groups G4, G5, G7, and G8, which did not show significant differences among them (p > 0.05). Groups G2 and G3 also showed similar results (p > 0.05) and were the least active compared to the others. CONCLUSIONS: EB potentiated the antimicrobial action of GIC against S. mutans and laser irradiation over GIC/EB presented better antimicrobials results. The results indicate that EB could be a potential photosensitizer for aPDT.

Mechanical properties of a glass ionomer cement incorporated with Amazon plant extract.

To evaluate the mechanical properties (MP) and antimicrobial activity of a glass ionomer cement (GIC) incorporated with an antimicrobial agent from the aerial parts of Dioscorea altissima. MP were: syneresis & imbibition; solubility; elasticity module; surface microhardness and fluoride release, and the anti-Streptococcus mutans (Smut) activity was accessed by microdilution broth assay and 3-(4,5-Dimethyl-2-thiazolyl)-2,5-diphenyl-2H-tetrazolium bromide (MTT) analysis. Syneresis & imbibition did not change over time for both groups, but EG showed lower values at days 7th and 30th. The control group (CG)'s and the experimental group (EG)'s weights were similar before the solubility assay, but after seven days, CG exhibited weight gain in comparison to EG. The elasticity module had no significant differences between groups. The CG showed lower surface microhardness compared to the EG. CG and EG had similar behaviors regarding fluoride release. EG showed diminished Streptococcus mutans count in comparison to CG. EG showed similar or better mechanical properties and an improvement in the antibacterial activity than the original cement.

Diazepam as attenuator of pain induced by dentin hypersensitivity in rats exposed to stress.

The pain in dentin hypersensitivity (DH) has distinct sensory and emotional origins, with variations that occur in different intensities for each individual. The aim of this study is to evaluate the effects of diazepam in the attenuation of the pain induced by DH. DESIGN: Fifty male Wistar rats were divided into five groups: control group received water ad libitum (C); stress group received water ad libitum plus stress (S); DH induced by erosion challenge with isotonic solution ad libitum (G); DH and stress (GS); and DH, stress and diazepam (GSD) groups. Animals of the GS group were exposed to the New York Subway Stress Model. Animals treated with diazepam (GSD group) received 1 mg/kg every 3 days, from the 15th day of treatment until the end of the stress-inducing period. The body weights of rats were weekly registered. After 30 days, all groups were submitted to the DH test, which was assessed using cold water stimuli, and were graded 0, 0.5, 1, 2, or 3. Dental elements were evaluated using scanning electron microscopy (SEM). RESULTS: 1) Groups G and GS presented the highest DH scores, which confirms that stress increased pain response; 2) GSD group had significantly reduced DH scores compared to G and GS groups; 3) SEM of dental elements showed exposed dentin tubules in G, GS, and GSD groups, as expected. CONCLUSIONS: diazepam attenuated pain induced by dentin hypersensitivity in rats exposed to stress.

Terapia interdisciplinar na otimização da estética vermelha e branca / Interdisciplinary therapy in the optimization of pink and white aesthetics ­ case report

Este relato descreveu um caso clínico no qual foi realizado um planejamento multidisciplinar priorizando, além do restabelecimento funcional, uma adequada estética ao paciente. Para que tais metas fossem alcançadas, foi importante a implementação de uma visão multidisciplinar do caso, garantindo um planejamento integrado capaz de reunir todos os requisitos para a otimização de resultados satisfatórios, considerando os padrões de estética periodontal e dental. O presente caso clínico descreveu uma abordagem clínica multidisciplinar para reabilitação anterior envolvendo cirurgia plástica periodontal, para aumento de coroa e confecção de facetas em resina composta pela técnica direta para devolução de estética dental, resultando em sucesso clínico e satisfação da paciente.

This report describes a clinical case in which a multidisciplinary planning was performed, prioritizing, in addition to functional restoration, adequate aesthetics to the patient. In order to achieve these goals, it was important to implement an interdisciplinary view of the case, guaranteeing an integrated planning capable of meeting all the requirements for the optimization of satisfactory results, considering the patterns of periodontal and dental aesthetics. The present case report describes a multidisciplinary clinical approach for previous rehabilitation involving periodontal plastic surgery for crown lengthening and direct composite resin veneers to retrieve dental esthetics achieving clinical success and patient satisfaction.

Depressive behavior induced by unpredictable chronic mild stress increases dentin hypersensitivity in rats.

OBJECTIVE: The present study evaluated the nociceptive response induced by dentin hypersensitivity after dental erosion in rats that were exhibited to unpredictable chronic mild stress (UCMS)-induced depressive-like behavior. DESIGN: Adult male rats were subjected to UCMS (depression [D] group) or not (no depression [ND] group) for 30days and received either acidic solution to induce dental erosion (E) or water (W), thus forming the WND, END, WD, and ED groups. After the end of treatment, depressive-like parameters (i.e., sucrose preference and immobility in the forced swim test) and dentin hypersensitivity were evaluated. Plasma tumor necrosis factor α (TNF-α) and corticosterone levels were measured, and astrocytic glial fibrillary acidic protein (GFAP) expression was evaluated in the prefrontal cortex, hippocampus, amygdala, and hypothalamus. RESULTS: Administration of the acidic solution potentiated dentin hypersensitivity and increased corticosterone levels in the ED group compared with the WD group. TNF-α levels only increased in the WD group. The ED group exhibited an increase in astrocytic GFAP expression in the hypothalamus and prefrontal cortex but decreases in the hippocampus. CONCLUSIONS: These results suggest that UCMS exacerbated the nociceptive response associated with dentin hypersensitivity, concomitant with an increase in plasma corticosterone levels. Hypothalamic and prefrontal cortex astrogliosis in the ED group may be attributable to the increase in corticosterone associated to UCMS procedure. The reduction of astrocytic GFAP expression in the hippocampus in the ED group supports the association between dentin hypersensitivity and depression.

Stress and its role in the dentin hypersensitivity in rats.

INTRODUCTION: The perception of pain varies individually. Chronic stress leads to analgesia. The use of animal chronic mild stress model to mimic human condition was previously developed and now applied in the evaluation of pain perception in rats with dentin hypersensitivity (DH). AIMS: Using DH model induced by dentin erosion (DE) mediated by acidic solution, the present study aimed the evaluation of the interaction of chronic stress and pain induced by DH in rats with DE. METHODS: DH was induced by ad libitum 30-day intake of acidic solution. Stress was induced by the New York subway model. Body weight was weekly taken, during treatment. Groups WO (water, no stress), WS (water and stress), EO (acidic solution, no stress) and ES (acidic solution, stress) were submitted to treatments. RESULTS: After 30 days, all groups were submitted to DH test assessed by cold water stimuli in the labial surface of molars, for 5s, and the rats responses were scored as grades 0, 0.5, 1, 2, or 3. After euthanasia, blood was taken to obtain the levels of corticosterone, stomachs were observed in fresh preparations, kidneys and livers were submitted to histological evaluation. Open field model supported stress evaluation, as did corticosterone analysis. Stressed animals showed significant increase in pain perception and a decrease in locomotion frequency, tending to be more frequent in the periphery of the arena, corroborating stressed behavior and the need of protection as a pain relief. Corticosterone levels were increased in the stressed rats with dentin erosion and also corroborate present findings. Finally, reduction in weight gain was impaired in stressed group with dentin erosion. CONCLUSION: The animal model enabled the evaluation of how chronic mild stress interfered in DH pain perception.

Dentin hypersensitivity induces anxiety and increases corticosterone serum levels in rats.

AIMS: Investigate the relationships between experimentally induced dentin hypersensitivity (DH) with behavioral, endocrine and dentin erosion data. METHODS: Male Wistar rats divided into four groups, two controls and two experimental, received tap water or isotonic solution (Gatorade®, lemon, pH2.7) for 30 or 45 days. The DH test was performed by a cold water stimulus on molars. A score (0-3) was given to the rats' pain response. Anxiety was evaluated by the elevated plus maze model and by serum corticosterone levels. The dentin erosion was observed by scanning electron microscopy (SEM). Anatomopathological studies were performed on the stomach, adrenal, kidney, and liver. RESULTS: Relative to control groups, experimental rats showed: 1) increased hypersensitivity scores (control group, 0; experimental groups, 2 (limits 0.5-3) on the 30th day and 2 (limits 1-3) on the 45th day); 2) reduced percentage of time and entries in the open arms and in serum corticosterone levels; 3) totally exposed dentinal tubules on the 30th day in SEM analysis of the teeth; and 4) no alterations in the anatomopathological and histological evaluations. CONCLUSIONS: The treatment with isotonic solution for 30 days was able to induce DH after erosive challenge and severe DH was observed after isotonic solution treatment for 45 days. The pain induced by cold stimuli was consistent with the grade of DH. The close relationships between dental erosion, response to pain, serum levels of corticosterone and the EPM behavior responses reveal the effects of DH at several levels.