Juliana Vianna Pereira

Antimicrobial activity of Arctium lappa constituents against microorganisms commonly found in endodontic infections

This study evaluated in vitro the antimicrobial activity of rough extracts from leaves of Arctium lappa and their phases. The following microorganisms, commonly found in the oral cavity, specifically in endodontic infections, were used: Enterococcus faecalis, Staphylococcus aureus, Pseudomonas aeruginosa, Bacillus subtilis and Candida albicans. The agar-diffusion method allowed detection of the hexanic phase as an inhibitor of microbial growth. Bioautographic assays identified antimicrobial substances in the extract. The results showed the existence, in the rough hexanic phase and in its fractions, of constituents that have retention factors (Rf) in three distinct zones, thereby suggesting the presence of active constituents with chemical structures of different polarities that exhibited specificity against the target microorganisms. It may be concluded that the Arctium lappa constituents exhibited a great microbial inhibition potential against the tested endodontic pathogens.

Evaluation of marginal leakage of different temporary restorative materials in Endodontics

Aim: The aim of this study is to assess the coronal marginal leakage of three temporary restorative materials used for root canal sealing after endodontic treatment. Materials and Methods: A total of 88 single-rooted teeth were submitted to biomechanical preparation and filled by lateral condensation technique. After obturation process, the teeth were randomly separated into four groups, being two teeth of each group used as positive and negative control. Temporary sealing was performed as follows: GI - Clip F (VOCO); GII - Bioplic (Biodinβmica); GIII - Vitremer (3M ESPE) and GIV - Ketak N100 (3M ESPE). Next, the specimens were immersed into Indian ink for 30 and 60- days, being 10 specimens for each time interval and then submitted to diaphanization to verify the amount of coronal leakage using a measuring microscope. Results: Leakage mean values within the 30-day period were as follows: Vitremer (0.3 mm), Ketak N100 and Clip F (0.6 mm) and Bioplic (1.7 mm). Within the 60-day period, leakage means were 1.1 mm, 1.5 mm, 2.2 mm and 2.6 mm, respectively. Conclusions: None of the materials was capable of preventing marginal leakage within the 30- and 60-day period. In both time intervals, Bioplic presented the highest mean of leakage and Vitremer the lowest.

Bacterial diversity in the saliva of patients with different oral hygiene indexes

The objective of the present study was to evaluate the bacterial diversity in the saliva of patients with different oral hygiene indexes using of two 16S rRNA gene libraries. Each library was composed of samples from patients with different averages of the differentiated Silness-Löe biofilm index: the first library (A) with an index between 1.0 and 3.0 (considered a high index) and the second library (B) between 0 and 0.5 (considered a low index). Saliva DNA was extracted and the 16S rRNA gene was amplified and cloned. The obtained sequences were compared with those stored at NCBI and RDP GenBank. The saliva of patients with high index presented five known genera - Streptococcus, Granulicatella, Gemella, Veillonella and Peptostreptococcus - and 33.3% of nonculturable bacteria grouped into 23 operational taxonomic units (OTUs). The saliva of patients with low index differed significantly from the first library (p=0.000) and was composed of 42 OTUs distributed into 11 known genera - Streptococcus, Granulicatella, Gemella, Veillonella, Oribacterium, Haemophilus, Escherichia, Neisseria, Prevotella, Capnocytophaga, Actinomyces - including 24.87% of nonculturable bacteria. It was possible to conclude that there is greater bacterial diversity in the saliva of patients with low dental plaque in relation to patients with high dental plaque.

In vitro assessment of antimicrobial activity of Pothomorphe umbellata extracts against Enterococcus faecalis

BACKGROUND Due to the complex anatomy of the root canal system, biomechanical preparation is not able to completely eliminate all microorganisms present in the endodontic infections, making it necessary the use of an intracanal medication. AIM The aim of this study was to assess the antimicrobial activity of an intracanal medication containing the ethyl-acetate fraction of Pothomorphe umbellata against Enterococcus faecalis. MATERIALS AND METHODS Fifty seven human maxillary canine teeth were used, of which 54 were infected with E. faecalis every 72 h, for 28 days, and cultured for 24 h. Contaminated teeth were randomly separated into three groups (n = 18) and treated as follows: Group I - calcium hydroxide-based medication; Group II - P. umbellata-based medication; Group III - contaminated teeth without medication. Three teeth were used as negative control. After 7, 14 and 28 days of treatment, six teeth from each group were assessed for the level of microbial growth after each period of treatment. RESULTS The intracanal medication containing P. umbellata was effective against E. faecalis after 7, 14, and 28 days of treatment without statistically significant difference in comparison to calcium hydroxide treatment (Kruskal-Wallis test, P > 0.05). CONCLUSION Ethyl-acetate fraction of P. umbellate was efficient against E. faecalis, making this phytotherapy a viable option for endodontic treatment.

Effect of Chewing Gum Containing CPP-ACP on Salivary Flow and Buffer Capacity: An in vivo Study

Objective: To evaluate salivary flow and buffer capacity by means of mechanical and chemical-mechanical stimuli, through the use of chewing gums. Material and Methods: The study was a cross-sectional study with 12 volunteers, divided into three groups, in three phases: Group A: paraffin gum; Group B: Chewing gum without sucrose, flavored (Trident ® ); Group C: Flavored chewing gum, without sucrose and amorphous calcium casein-phosphate phosphopeptide (Trident Total ® ). The stimulated total saliva was collected after 5 minutes of mastication of one of the products and the volume was expressed in mL / min. The same sample was submitted to pH measurement with the use of a digital potentiometer, where the results were classified in normal buffer capacity (final pH between 5.0 and 7.0) or low (final pH <4.0). The results were evaluated regarding the normality of the sample distribution (Shapiro-Wilk test), Analysis of Variance (ANOVA) and Tukeys test. Results: Chewing gums increased the salivary flow of the volunteers, when compared to the control group (paraffin) (1.53 mL / min), differing statistically from the group, although there was no difference between Trident ® (2.09 mL / Min) and Trident Total ® (2.06mL / min). Regarding the buffer capacity, the values obtained were 6.94 (paraffin), 6.99 (Trident ® ) and 6.93 (Trident Total ® ), with no difference between groups (p = 0.713). Conclusion: It was concluded that chewing gums, with and without CPP-ACP, increased the salivary flow in relation to the control group. In relation to buffer capacity the values obtained for chewing gums with and without CPP-ACP, are shown to be within the normal range.

In vitro evaluation of the effect of vinegar solutions on the microhardness of root dentin

Objective: This in vitro study evaluated the action of vinegar solutions on microhardness of root dentin. Methods: Ten extracted human maxillary central incisors were sectioned transversely at the cementenamel junction. The roots were fixed on cutting machine device and were cut on cervical region transversely in 2-mm sections. The second cervical section was divided into four parts. Each one quarter of section was fixed with wax in the center of a pre-fabricated acrylic disc. Four treatment groups were tested: group 1 – alcohol vinegar; group 2 – white wine vinegar; group 3 – EDTA (standard group); group 4 – distilled water (control group). The specimens were submitted to solutions application for 5 min. The measurements of microhardness (initial and post-treatment) were carried out using a Knoop microhardness tester. Data were analyzed by using Wilcoxon and Kruskal Wallis tests. Results: The analysis of initial and final microhardness showed statically significant differences before and after application of the tested solutions alcohol vinegar, white wine vinegar and EDTA. Groups 1,2 and 3 presented a decrease in the microhardness values. Conclusion: The solutions of alcohol vinegar and white wine vinegar, as well as the EDTA, reduced the microhardness of root dentin.

Evaluation of commercial fluoride solutions on bovine enamel demineralization, using pH-cycling model

OBJETIVO: O objetivo deste estudo in vitro foi analisar a concentracao de fluor em diferentes solucoes fluoretadas para bochechos e sua capacidade de interferir no processo de carie. METODOLOGIA: A analise da concentracao de fluor nas solucoes para bochecho foi realizada com eletrodo especifico para ion fluor acoplado a um analisador de ions Orion. Blocos de esmalte de dentes incisivos bovinos com a microdureza superficial conhecida foram submetidos a ciclagem de pH e uso de solucoes fluoretadas, sendo, posteriormente, avaliados por uma nova analise de microdureza e tambem pela incorporacao de fluor. RESULTADOS: As concentracoes de fluor (ppm) encontradas nas solucoes SANiFill®, Colgate® Plax®, Oral B®, Sorriso® e Cepacol® (nao fluoretada) foram, respectivamente: 245,94; 247,61; 251,50; 258,01 e 38,44. A menor perda de porcentagem de dureza superficial foi observada com o uso da solucao fluoretada Sorriso® (29,7%±14,4), seguida por Colgate® Plax® (33%±14,1) e Oral B® (43%±18,3). Todas as solucoes fluoretadas analisadas mostraram capacidade de incorporar fluor no esmalte dental. CONCLUSAO: Os dados sugerem que as solucoes fluoretadas foram capazes de interferir nos fenomenos de desmineralizacao e remineralizacao, promover incorporacao de fluor e, consequentemente, diminuir a perda de dureza no esmalte dental.